AMMO

I would have thought that depends what dry sump and alternator you have. If you have an external pump and if the alternator is on the left or the right. Personally I would bolt all these on and check for yourself. There are some lugs that are not used at all. I had an old damaged block marked so I could take them off but that went off to the tip. Customers didn't seem to want to pay extra to have the lugs removed on a milling machine so I have never done it. I have always intended to do this to my own engine. If it needs to come out at some stage I will give it a go. You could do some of it with a hacksaw and file. Doubt you will save that much weight but it all helps.

Interesting article that explains BMEP much better than I can here The formula I use to work out BMEP is torque in ft lb x 2.475 / capacity of the engine in litres. I have just worked out all the BMEP figures for all my engines that appear on the dyno-plot website here I have built many more Duratecs than that and should load more graphs but the ones that appear on the site will do for now. Here are the figures for some of the more important engines: 210 2 litre 217.7 bhp / 164.2 ft lb / 203.4 psi BMEP 220 2 litre 226.7 bhp /171 ft lb / 212.5 psi BMEP 260 2 litre 263 bhp / 183.6 ft lb/ 227.4 psi BMEP 280 2 litre 286.5 bhp / 186.4 ft lb / 230.9 psi BMEP 300 2.3 litre 298 bhp / 219.5 ft.lb / 232.16 psi BMEP * 300 2.445 litre 307.5 bhp /224.8 / 227.55 psi BMEP 310 2.2 litre 312.6 bhp / 200.7 ft lb / 226.8 psi BMEP * Dyno runs on this engine were not finished as it was late and I wanted to get home. It was a very well developed engine that was built after the 2445 cc engine. It is in fact a 2.340 cc with 89 mm bore and 94 mm stroke. By optimising the induction lengths and cam timing I am confident we would have seen at least another 5 to 10 bhp. It certainly had the torque to do it. The reason I wanted to get it home was that I had a 2.2 litre crank, rods and pistons waiting to go in. The 2.3 engine was finished as far as I was concerned. I had lost interest in it to the point that I didn't want to waste another hour fiddling with it to find out what it made. The 2.340cc engine had the crank, rods and pistons removed and became the 9,000 rpm 310 bhp 2.2. This was the first engine I felt was truly my own, made the way I wanted. The reason for de-stroking is so we could rev the engine further and make use of the breathing ability of the head. The fact that the same head made 312 bhp on a 2.2 would indicated from experience that it would have made around the same power and a 2.3 but with more torque and less revs. The fact that it has less torque is of no real relevance if the car is geared right. I would argue that less torque might actually be better in a light car. After all we aren't Americans who rely on big cubes. I like to think we Europeans do things with a bit more finesse. Why do F1 and MotoGP chase horsepower and rpm rather than torque? Big capacity is OK in a rally car but in a Seven I personally like the idea of a 2 litre. The 2445 cc engine was comparable to something like a Millington Diamond 2.5 that is used in rallying. It even sounded a bit like this one Back to BMEP. As you can see all the engines are in the region of 230 psi. According to the article linked above that is more or less the accepted maximum figure. The engine designer who is drawing my new 2 litre crank also agrees with the 230 psi figure and would be suspicious of anything much higher. Dave Walker who put the flea in my ear has also never seen a 2 litre with more than around 185 ft lb of torque. I am confident that once we have the new crank and a few other bits we will see the 2 litre engine come into its own finally when we get to rev it to 9,500 rpm. In the BMEP article that is linked above they also mention F1 engines with 206 ft lb of torque and 220 psi BMEP and Nascar Cup engines with 226 psi BMEP. Talking of Americans and big cubes, how about a 1,000 cubic inch /16.5 litre V8 with 2,150 bhp and 1,500 ft lb of torque. here The BMEP for the big V8? 226 psi. This engine won't last long at 9,000 rpm and something like piston speeds of an astonishing 38 metres a second. How about 32mm cam lift? On the drag strip if it does a 7 second pass the engine will have rotated only around 8,000 times. I wonder how many passes you can make before you need a re-build? Torque or no torque, I think I'll stick to the Duratec with total capacity of 2 litres instead of V8's with cylinders of over two litres. Hope you found some of this interesting.

7 Wonders, link doesn't work for me. Can you give it another go please? Back to Duratec porting. The other night I was looking at dyno graphs and I found one that was not from Emerald but from the two Steves at Track'n'Road. The customer's name was on it which jogged my memory. It was the graph of a Duratec R500 that I had rebuilt after it had dropped a valve and made a bit of a mess of the head. Sometimes when an engine drops a valve the head can be brought back from the dead by welding, fitting new seats and fettling. I've done a few in the past but in this case the spark plug and spark plug hole had taken a bit of a battering and as there is a coolant passage around the plug (how many of you knew that?) I opted to start with a new head. Rather than buy a CNC head (fitted as standard to the R500) to save money and time I opted to port by hand, something I advocate on a Duratec with stock size valves as the original ports are pretty close to being optimal out of the box and are very close to the proportions and dimensions I have been using for a very long time. There is a good story about this but I don't want to go off at too much of a tangent. The dyno sheet is dated 2011 so it was probably one of the last engines I built. The result looked good but I had nothing to compare it to. I called the two Steves, had a chat about this and that and asked if I could have a graph from a standard R500. Steve Greenauld emailed me the information at about 3 am and was surprised when I sent him a thank you note in reply. Seems like I'm not the only one who is up in the middle of the night! The graphs show that the stock R500 made 259 bhp @ 8,500 and 170 ft.lb of torque and the re-built engine made 269 bhp also @ 8,500 rpm and 178 ft.lb of torque. The engines have the same pistons, rods, cams, compression, etc. The differences were the head, a keyed and balanced crank and all the other bits and pieces that I do, and a Raceco silencer. In the morning I called the customer up who re-confirmed that the engine felt smoother and had more urge than before.* He also said that Steve Greenauld told him at the time that if he could have revved it more it would have made more power. Caterham produce a fine car with a fine engine in it. This post is in no way aimed at detracting from what they do. They have to produce engines to fit to cars within a time limit, with constraints on budget and make sure that they are all the same, hence the CNC head. It all makes perfect sense if you are producing cars commercially that you do it this way. The way I make engines is different. The R500 I re-built had a lot more time put into it and costs more to produce. As the post is to do with porting the conclusion I have come to and that I have been an advocate of is that it is possible port a Duratec by hand and obtain good, if not better results than the head that is currently fitted to the R500. As I do not port heads commercially anymore I'm not blowing my own trumpet to get work. Just in case anyone was speculating. The only heads I want to port from now on are for race engines over 280 bhp and development heads for the flowbench to put finishing touches to the work already done. In fact for the DIYers I may at some point make all the findings on the head public so that those who are interested can do the porting themselves. Another snippet of information is that the engine in my own car that was running before that R500 was introduced also runs exactly the same pistons, rods, cams and compression as an R500. The main difference is that it has the early head made 263 bhp and 183 ft lb of torque. This is with 48mm Jenvey throttle bodies and an experimental exhaust and collector that I never produced commercially. A year after it was built it made 268 bhp which justifies my claim of the engine usually making around 5 bhp more after they have been run for a while. Something I have seen on quite a few engines. These measurements were taken at Emerald so it may not be fair to compare them to the Track'n'road figure as there could be a a horsepower or two difference either way. *On the subject of smoothness Dave Walker said a couple of interesting things to me recently. Since he has installed the Superflow 902 engine dyno he can't feel what the engine is doing anymore, whether it is vibrating or feeling happy. He also said that some of the big engines, up to 2445cc I produced didn't feel that nice in the car. His favourite Duratec is the 2 litre as it is also the smoothest. As the 2 litre engines are plentiful second hand it seems to me that these are the engines that I want to concentrate on and perfect. I am pretty confident that the ports, cams and throttle bodies are there or there abouts and require little or no work. Things to look at now are crank, valve springs and exhaust. When I have time I will write something more about porting, how I got into it and what I learnt very early on is still applicable now. At some point I will pull up all the posts that I have written on an off here over that last ten years or so an use them as a basis for articles that will be collated into some sort of tuning book with stories from the racing days. I had a drink with Mankee last night who will do the proof reading for me (thanks to the others who also offered). I told him a few war stories that he seemed to enjoy but I often wonder if what I have to say is of any interest. I decided that the main reason for doing this is as a legacy to my sons. So they can see how their father spent his time. That's a good enough reason for me.

The consensus of opinion on that type of collector an a V-Twin is that the advantages outweigh the disadvantages. Things that would affect the running of each individual cylinder could be the firing order, one cylinder will be doing more work than the other, the crank rotation and how much oil is thrown into each bore. V-Twins get better lubrication to the left hand bore. Don't know if this is the same on boxer twins. In the very old days if a Guzzi V-Twin did have a piston part seize in the bore or pick up it was usually the right hand side. I've heard of V8s being the same. Something that stuck in my mind a long time ago is that there was a Messerschmitt V8 supercharged fighter plane engine that ran different compression ratios on each bank. 8.5:1 on the left and 8:1 on the right. I always wondered if this was to stop the right hand seizing or if it was for some other reason. In the case of the 2CV it could be that the collector wasn't made exactly as it could be because of packaging constraints. Maybe the silencer has to go to either one side or the other of the engine. I think the collector needs to be more symmetrical and more of and X shape where it joins. If you look at the right hand pipe after the collector it looks hotter than the left hand one. The hot gasses are following the path of least resistance. I would maybe have joined them centrally over the top of the engine and had one pipe go off to the right and one to the left rather than both to the left. That would have perhaps made a some difference. As an alternative for a boxer twin you you could run two completely separate tuned length headers and silencers with no connection between them or with a balance pipe at the right point to be determined. The latter should give more torque than the individual pipes. I have run both configurations. However, the guys that are tuning the 2CV seem to know a what they are doing and if they have opted for a 2-1-2 system I reckon it must be for a reason. I wonder if it has two silencers?

As long as there is enough spline engaged and the oil seal is not too close to the edge it could be OK. Have you tried fitting it to see what it looks like installed? More to the point why did you have a new one made and not just re-condition the old one with heavy duty spiders? Is there something you're not telling us? Spill the beans.

Looks like the Belgian guys have done a lot of the work on the 2CV. Their steel one piece crank is similar to what I had in mind. It would be cheaper to buy their crank than to develop your own. Something I noticed from the video here it looks like they are running a 2 into 1 into two similar to what I ran on my race Guzzi. If you watch the dyno run you can see that the left hand header is getting hotter than the right hand one which indicates that it is running leaner. When you run an exhaust like this on a V-Twin the exhaust scavenges one cylinder and interferes with the other at certain rpm. As the plug chops indicated that the left cylinder was running leaner I flow tested all the injectors I had and fitted one with higher flow to the left cylinder. This evened things out and was a good temporary solution. In the end we ran a lambda probe in each exhaust header and data logged the fuelling. From the lambda traces you could see one cylinder going rich and the other lean. Even with the old Weber Marelli P8 ECU we could re-program each cylinder individually to solve the problem. This was 1996. I haven't even got close to doing anything similar with a 4 cylinder engine yet. I have always wondered what number 4 cylinder is doing on a Duratec with its tortuous exhaust port. I have thermocouples I could put in the headers and find out but it would be opening a can of worms I don't want to open. Individual cylinder optimization is something you do when you have already done everything else and we are not even close to that yet. Even with a humble 2CV you could get carried away if you have the budget to do it. Depends how obsessed you are. In the 80s I quit my job, made myself 22K overdrawn in the bank, sold both my road motorcycles, juggled credit cards, using one to pay of the other and re-mortgaged my house to go racing an air-cooled V-Twin with shaft drive. Probably the stupidest bike in the world to race. I worked on the principle that I would never have the money to do it or if I eventually did I would be too old to go gallavanting around. It eventually came good when we got factory sponsored. If I had the chance to do it again I would not change a thing. The problem you have 2CV is that you are just not obsessed enough. 😬

Hi 2CV I suppose the very first thing I always look at to determine the potential of an engine when someone brings me one for assessment is the intake valve area. From the area with the aid of some simple calculations you can make predictions of the power potential of the engine. I would say that producing power from an engine is a combination of empirical testing (flow benches, dynos and race tracks), educated guess work based on past experience and a creative mind. The creative mind is an important aspect in my view. Without this no innovation is possible. We would still be running pushrod engines with two valves per cylinder and carburettors without innovation. In the early days I've was very fortunate to have mixed with some very clever people and have learnt a lot from them. It is a source of great pride that now some of these people call me up to ask my opinion. Once upon a time it was the other way around. One of them called me last night. He was building engines that would finish 24 hour endurance races when I was still learning. The person in question has lots of experience but is still asking himself questions and looking for answers. I was fortunate that I did a year in 24 hour Endurance as one season of 24 hour racing is like doing ten seasons of normal racing. You learn a lot. I quit my job as a workshop manager to do it and started my own business as an engine tuner. What was to become Raceco was started on February the 14th 1986. Another anniversary coming up in a couple of days. To give you an idea of how far we have come my first dyno session was in December 1985. The FZ Yamaha 750 we were testing on the Schenck at Mistral Engineering in Stoke Newington made 104bhp. Roll things forward to 1998 and the Suzuki 750 I had some involvement in made 162bhp at 15,000 rpm. From 138 bhp per litre to 216 bhp. Makes the 150 bhp per litre of the Duratec seem quite tame. The parts alone to update the road Suzuki engine into a race engine cost £85,000.00 at the time. Some of the parts I supplied to Crescent / Rizla Suzuki got sent of to Japan and put into the World Superbike kits by Suzuki. It was a fun time and like now I spent a lot of time awake at night thinking about things. Another thing that springs to mind is that when we were racing against factory Ducatis and watching Superbike races is that every year new bits would come out. Ducati had new exhaust systems, larger throttle bodies with dual injectors, fuel pumps. Development never stopped, it was never over, nobody ever said "That's it, that's as far as we can go". There comes a time with an engine, or cylinder head for that matter, that you say that it is not worth continuing due to the law of diminishing returns. Time to move onto something else. The FZ Yamaha was replaced by a Honda RC30. The Guzzi 2 valve carburettor bike by a 4 valve fuel injected one. In the case of the Duratec we still haven't reached the stage where development is complete or a better N/A engine has turned up. When it comes to tuning there are so many variables that sometimes my head swims with all the possibilities. The person that thinks that tuning engines is simple maybe hasn't thought about all the variables. I spent eleven years of my life at the side of racetracks trying to make things go faster. I built my first race engine in 1984. After almost 30 years I know almost bugger all. I haven't even started to scratch the surface. At the moment I am somewhere in the ball park with the Duratec head but all the questions I have been asking myself still haven't been answered. It works well in conjunction with the cams and throttle bodies I designed but I have only designed three cams for this engine. There are still possibilities to explore there. If there was 10K available I would undertake some serious exhaust development. What we are running now is made to my specification but based on an educated guess based on past experience. It is good enough but far from perfect. Apart from the ports, the cams and the throttle bodies it is the exhaust that fills and empties the cylinder. I don't even know if I answered your original question 2CV. I suppose the limiting factor to making power is how many new bits you can afford to design and test. The limiting factor is money. That is why your 2CV engine is making only 30bhp and my 2 litre Duratec only 280 bhp. If more money was available we would be further down the line. Edited to add a link to the 24 Hour Endurance bike racing team I was involved with in 1986 for those who are interested. here Edited by - AMMO on 12 Feb 2013 09:25:00

Let's go back to basics. What is written below can be the basis for some discussions. The reason I have gone back to quite an old post is because since then quite a few engines have been built and many dyno tests have been done and quite a few facts discovered. When I say dyno I mean the rolling road at Emerald. Dyno is shorter than writing rolling road every time. The flow bench tests were all done on a Superflow 600 and all the dyno graphs, unless otherwise stated, are from Emerald. The following was posted quite a few years ago and lifted word for word with no changes from the original post: Posted - 23 December 2003 18:36 I finally managed to fire up the new Superflow 600 in anger for the first time today at 3 pm. Just before the workshop closes down until January. I did some quick and dirty testing on a Duratec head which has cylinder #1 left standard. The other cylinders have been modified in different ways. I have left the head on the bench and will do some more detailed testing in the New Year. All testing was done at 25” of water. To convert to 10” divide by 1.58. I did some testing at 10” and at 25” to check that the conversion is correct. The exhaust ports have also been modified but I will have to wait until later to test them. Cylinder #1 was tested with 11 mm of lift using a Kent cam at full lift as a valve lifter with a Raceline direct to head throttle body and 90 mm trumpet. Normally I check at 1 mm increments and over-lift to see if there is any benefit in using a higher lift cam. Not enough time. The test was on a completely standard intake ports with no mods. The result was 213.2 cfm. Enough flow for 232 bhp. This is in theory with the correct cams and exhaust. With short 260 / 270 degree road cams the 2 litre has been dyno tested at around 210 / 220 bhp. Cylinder #2 as above plus a very small mod to the short side of the port just before the seat. The stock port has a tumble feature which I removed. The result was 226 cfm / 246 bhp potential. Cylinder #3 as above but with mods to the throat. 231.2 cfm / 251 bhp potential. Cylinder #4 as above but has has the ports cleaned up but not enlarged by much. 237. 2 cfm / 258 bhp potential. This is equivalent to 150 cfm at 10” which is what I predicted months ago the head was capable of doing without too much work. It is possible to get more if you are willing to put the work in. I'm aiming for a mere 220 bhp for my own engine. Probably more than I know what to do with. I am very happy with the results. To achieve the same results with a lesser head would take more than the cost of a Duratec donor engine. Some heads will never achieve this because they just cannot accomodate the valve sizes. I am convinced that the Duratec will become the engine to have. There is nothing else out there that I have seen that can give these sort of cfm figures with so little work. AMMO Back to today. The above was written when very few Duratecs had found their way into Caterhams. There was a lot of resistance to these engines by the K-Series and VX crowd. Talk about reliability and if they really had the potential to make the 300 bhp I claimed. I joked at the time that these engines would be embraced once they were discontinued. I have heard a rumour that this will be next year. The above flowbench figures are for the early 2 litre / 2.3 Ranger head which is inferior to the late head (but still bloody good). Some people call the late head a high port head. The inlet at the gasket face is the same as on the early head. For me a high port head is a head that has had the induction angle changed to a higher, steeper angle moving the port entry higher. I looked at doing this but it required too much work. I will refer to the heads as early and late. Late heads came in around 2004. To get the ball rolling Ben Willis' 210 bhp engine fitted to had work done only to the throats, was fitted with DTEC 10 260 degree cams and made 217bhp. Graph here Some years later Ben brought his car to one of the dyno events held at Emerald and when re-tested it made 226 bhp. 9 bhp more that when it was new. I always say the engines make around 5 bhp after they have been run in but in this case it made more than expected. I don't have the graph for this but maybe Ben still has. This is far off from the 246 bhp predicted but than nobody has had the balls to stick 280 degree or perhaps higher duration cams on an early head with hardly any work and see what happens. The next step is the 220 bhp engine and by that time I go for the full porting job and 270 degree cams. Graph here I did build ten 210 bhp spec engines for Elises. Some have done some pretty high mileages by now. When we built a couple of engines with 260 degree cams and full porting jobs as opposed to just working on the throats they still made the same power. In other words improving the head made no improvement to the power. The cam was holding the engine back. Virtually the same head as the 220 bhp engine but with maybe a bit more attention paid to the porting and 48mm throttle bodies instead of 45mm does this here 260 bhp. You could make the same power on 45's but the 48's were fitted as they left the option open to make more power later. If I remember correctly a few weeks after these tests were done Pete McEwen from Raceline sent me a late head to test. We got 158 cfm @ 10" straight out of the box. With no porting this is as good as a ported early head. Again to my knowledge nobody has tested this head on an engine with decent cams and throttle bodies but there is no reason to believe it wouldn't make 260 bhp out of the box. If money and time were no object I would try it. Once ported the late head with my own cams and throttle bodies it does this on a 2 litre. http://www.dyno-plot.co.uk/dyno/dynoplot/id%3D535%26sort%3Drec%26but_sea%3Dqs%26sea_simple%3Draceco/Westfield-RACECO-UK.htm If you then go to town, put bigger valves in and increase the capacity to 2.2 you have this here Once development is done on the 2 litre I am hoping to see 295 / 300 bhp. I can't see vast increases in torque from this engine and the extra power will come from higher rpm. The head on the Duratec is very good as standard, especially the late head that has a much better port shape. Don't dismiss the early head if 260 bhp or lower is your target. The first 300 bhp engine I built had an early head with 1mm larger valves. It was 2445cc though. here The development of the engine wasn't easy. The early version made only 276bhp and caused many sleepless nights. Lots of new parts had to be made. The other thing to keep into account is the size of the throttle body. I have figures of ported heads with different throttle bodies on. In many cases the throttle body can add a restriction and decrease the airflow. The throttle body, port and airflow have to be in proportion with each other. If big power is required a 54mm throttle body with the stock 35mm valve sizes is about right. On a bigger valve head the 54mm bodies restrict the flow so an even larger size would work. At the risk of repeating myself I have been using these size throttle bodies on twin and single cylinder motorcycle engines since the mid 90s. It is nothing new. The stock throttle body size for a 1993 Moto Guzzi Daytona is 50mm on a road bike. A race Ducati had 60mm and a Race Honda a 65mm body per cylinder. The work I did with Suzuki on four cylinder engines in the 90s was mainly to do with the cylinder head and airflow. The 750 cc engine had 45mm bodies whilst the 1000cc engine had 50mm.* The thing about using smaller than required throttle bodies on car engines is a throwback to carburettor engines and the requirement to have a Venturi to drag the fuel out of the float bowl. With fuel injection everything changed and we can run a much better throttle body / port shape with higher flow than before. I did some work on old racing Porsche 911S and 911Ts. The port size on the carburettor heads were much smaller than those fitted with mechanical fuel injection. There is no need to run a bigger throttle body than you need to make the power you want although it seems that it not detrimental if you do. One negative effect is that low throttle opening control suffers as there is a rush of air when you open the throttle. This can be controlled with a suitable linkage although on a race engine that is running a between 5,000 and 9,000 rpm it is not required. There is no point in running a bigger port, or valve size if the engine and target horsepower does not require it. All components, cylinder head, cams, throttle bodies and exhaust have to work in harmony to produce the best result. * Edited to add a point about the Suzukis. When the throttle bodies were added to the Suzuki heads the head did not "see" them on the flowbench. In other words the flow of the bare head with a radiused inlet was not decreased by the addition of the throttle body. Every modified Duratec head I have tested has had its flow reduced when a throttle body has been fitted. I have tested quite a few different size bodies as well as my own 54mm bodies. The 54s outflow everything else, but when added to the head caused a 1.5% reduction in flow. There is just enough room to bore these bodies to 56mm but with the 2 litre wanting to go to 10,000 rpm as it is I can't see any point at the moment. Again it is not the airflow that is stopping the engine making power, it is the rpm. Edited by - Ammo on 11 Feb 2013 12:48:07

Most of the diff sold to Wrightpayne. Empty bare main casing still available. £10.00 + delivery.

Thank you John for your very kind offer. Next weekend I will be going to a memorial dinner for one of the mechanics I worked with at Team MCN. The 26th anniversary since his death in a road accident. A couple of the guys that will be coming are journos so I will be picking their brains. Many years ago I wrote a couple of things for Superbike magazine. I'm fortunate that I know quite a few people, Gary Pinchin, Mat Oxley, Julian Ryder the TV commentator, Neil Spalding, Alan Cathcart etc. Out of all of them I think Alan Cathcart has the best handle on things. He interviewed me at the height of our racing success and the article got syndicated, translated into many different languages and printed worldwide. At the time there was talk of him working for 53 different magazines. As writing probably pays about the same now as it did twenty years ago it makes sense to sell the same article to more than one publication. I interviewed a few people in the old days when I was going to write the aborted Moto Guzzi book. I found some mini cassette tapes the other day but have nothing to play them on. I'm pretty sure there is an interview I did with the late Umberto Todero at Moto Guzzi. There's an article right there for some classic bike magazines. Then there is the ancient history of my own race team and the development of the Moto Guzzi Daytona. I could fill quite a few pages with that. Thanks again for the encouragement and offers of help. I've got a feeling I could quite get into this writing lark.

No, definitely a 7". Will send you an email.

Just checked it. Mine is a 7" diff. Isn't that what is fitted to a Caterham?

It has the input flange, end cover and big ali threaded adjusters / oil seal housings.

Had some of the insides nicked out of it. Would suit someone who wants to put a new crown wheel and pinion / LSD in it or needs a donor casing to send to one of the transmission specialists. £25.00. Buyer collects, GONADS or courier can be arranged.

Allen, I don't build engines anymore. I support existing customers have had engines built by me, it would be wrong not to, and I will build race engines for those that want them and have no problems with my attitude on pricing. Building run of the mill engines that everybody is also doing is not a good idea from a business point of view in my opinion. You have to compete on price. All the engine builders I know, and I know quite a few, are moaning that they want to get out. Some have already gone to the wall. Since I stopped building engines my turnover is way down but my profit is up! I'm not talking percentage, I'm talking actual money. Engine building is time consuming. Hours of talks before getting the job (if you get it and if the customer doesn't go elsewhere with all the information you stupidly gave him), more hours than you actually bill for building the engine and then hours talking about it when you are trying to help out with the installation. The race engine I built recently built was for a man who was determined that I should build it. I tried very hard to send him elsewhere but he was insistent as he races a car against someone else who has one of my engines. The guy is as good as gold, works in motorsport engineering at a pretty prestigious level, didn't want to know about cams, valve spring pressures or any of that stuff people seem to want to know. He didn't quibble about money, an issue that is very important to me! From my side of the bargain, the engine was delivered on time at the price agreed. I had told him it would make 280 bhp and 185 ft. lb. of torque and that's what it made. On top of which we are going to progress the project further. I am only interested in development. I will upgrade my own customer engines and supply kits for people to build their own engines but the days of building the 210 to 260 bhp engines are over and have been for some time. Just not interested in them. "Suck...Squeeze....BANG....Blow....they all work on the same principle." Pretty much. I find that it's how hard they suck and bang that makes the difference. 😬

Thanks for the offer Oliver. I proof read a Moto Guzzi book for Mick Walker back in the 80s. Mainly to make sure the technical aspects were accurate. I would like my writing proof read to correct typos, spelling and grammar. I'm not keen to send out work that has mistakes in. OK for an internet forum to make the odd error, but not in published work. I think I will start small, just with some articles. There is a new glossy classic motorcycle magazine starting up soon. I have already been approached by someone about it. As for compiling articles into a book I think that was done years ago with the one Phil Irving wrote under the name "Sliderule". Irving was the designer of the Vincent engine. He also wrote the book Tuning for Speed. I have seen copies of Vizard's book Tuning the A Series engine on bookshelves at some of the race engine builders I have visited. It is highly regarded. It would be nice to do something like that. The royalties would be coming in for years! :-) Thanks for you encouragement.

I swopped my standard calipers for an early Hi Spec kit with 250mm solid discs some years ago. Mainly to save weight. If I remember correctly I saved four kilos. They brakes are OK for road use but I never really liked the EBC Green Stuff brake pads fitted. I changed the pads for Pagid Blue at the front and fitted new standard road pads at the back. Seems to work OK on the road but on track the brakes can go off a little bit after a while. I kept the standard master cylinder and changed the leverage ratio at the pedal. I like the pedal slightly long so I can apply just the right amount of pressure. Might not be to everyone's liking. When we raced motorcycles we were sponsored by Brembo. We used a billet caliper and found that the brakes would fade after a while. Reverting back to a Brembo road caliper that was cast, bigger and heavier worked better as the heat was dissipated better. Later we were sponsored by a company called PFM that made brake calipers and discs. Their brakes were fantastic.We used them in conjunction with bake pads from Performance Friction and Castrol SRF brake fluid. PFM also have brake testing equipment. They have tested a lot of calipers and told me that amongst the best for rigidity are Alcon. If I was doing it all over again and they were still available I would be looking to get Alcons to go on the standard discs with Pagid or Performance Friction pads and SRF fluid. Alternatively the AP racing kit, although for my own use I would question the necessity of a vented disc. I do believe that the caliper has to have more bulk than the one I am currently using. Both for stiffness and heat dissipation. As I hardly use the brakes on the road I will stick with what I have got. People that have followed me on the road have told me that my brake lights don't work but in reality I like to keep up a momentum and go through bends at the right speed without braking. The thing I like about the Pagids is the initial bite from cold. When you do need to brake It is nice to know there will be something there. Some of the racing pads don't stop you until they are hot. I never seem to get my brakes that hot unless I am on the track. From memory the standard calipers were OK. I only changed them because they were so heavy. Edited to add that brakes are a very personal thing. What works for one person may not for another. One of the problems we had when I was spannering in 24 Hour Endurance was that we had three riders and that the bike had to be set up so it would work for all three. When I did a year with Rizla Suzuki the two riders had a bike each. Both braking systems were totally different with different master cylinder and pads. A bit of experimentation is required to end up with what works best for each individual. Edited by - AMMO on 8 Feb 2013 07:06:34

Thanks for the positive comments. Keep them coming! 😬 Everyone likes a pat on the back now and again. I just read some of this and realised that there was a typo in a post that Mankee spotted. The reason I want to meet up with Mankee is that I am thinking of writing some articles and possibly a book and need someone to proof read my scribblings. Thinking of an anecdote and photo rich technical book. The sort of thing I like to talk about with friends but with flowbench figures and dyno graphs. Something that is an interesting read that also imparts tuning knowledge. I've been asked to write books on two occasions. The first was on Moto Guzzis around twenty years ago. I actually took an advance on this that I returned after a few months when I realised what a huge task it was and that I would be working for a pound an hour. The second was a tuning book on Duratecs very early on when I knew even less than I know now about the subject. Dave Walker put me forward for this. I again refused as the money was abysmal and the royalties not that great either. Thinking of self publishing perhaps. Maybe a toe in the water with some articles to start?

More talks with the engine designer regarding my new crank. Discussed BMEP figures and maximum rpm. He's ex-Cosworth and mentioned BDA's so later yesterday evening I dug out a book on Cosworth engines I had bought in the 80s. In the book I found some typed sheets stapled together dated 1964 that I had been given by Cosworth in 1984 when I designed my first piston for a Moto Guzzi. They refer to the SCA, a 1000 cc engine that had much in common with the Moto Guzzi V50 previously mentioned. Bore, stroke, valve sizes and the fact they both had Heron heads is what made me interested in the SCA at the time. I suppose the fact that I had a batch of pistons made for a big Guzzi and the SCA was twenty years old is what allowed me to get this information from Cosworth. Basically with the V50 Guzzi I had built half an SCA in V-Twin form. The pistons for the big Guzzi were 88mm race pistons to my design and specifications but with a lot of help from the late Geoff Roper, head of the piston department. I remember driving up to Cosworth in my brand new red little Astra van with a Guzzi engine in the back. In Geoff's office we looked at the squish clearances and pin to deck heights and valve to piston clearances. These pistons were to go into my very first race engine. There are still some road bikes running around with these pistons in almost thirty years later. After the first race I stripped the engine and was very concerned that there was no sign of carbon around the edges of the piston. I phoned Geoff at Cosworth to voice my concerns. He patiently explained that when the squish is working properly that is what happens. Lots of water under the bridge since then. I went to visit Cosworth again in 2005. Big changes. The old guys with white lab coats and swarf on the office carpet have gone. A much sleeker operation with lots of young people with computers rather than drawing boards. I looked up to the older generation of people like Geoff Roper. People who were there in the 60's when the DFV was born and a load of other exciting things were happening. Someone I know at Cosworth recently retired and was probably the last person still working there that knew Geoff. When someone last week "discovers" a thing called squish my first reaction is to say "Listen, I was doing this thirty years ago". But then I remember Geoff and how patient he was with me when I was green behind the ears and full of questions. In fact the word squish and the name Geoff Roper will always be associated. One day I will make a list of all the older guys that helped me. Not a long list, but some people were instrumental in teaching me some of the minsicule amount of things I know about four stroke engines. The subject is vast. I am always wary of the person that knows everything about engines. As far as I know he (or she) hasn't be born yet.

Sounds like you've already done the first easy stage then. The next phase is going to cost money. Looks like you are in the same boat as me with the 2CV as I am with my Duratec. Frustrating waiting years to do stuff you want to do but can't afford to.

Hi Eugene. Zetecs are nice engines. As for what stops the engine revving I'd be looking at cylinder head, cams, induction and exhaust system. The willingness to rev in a Duratec is due to the exceptional flow capabilities of the head in standard and modified form for starters. Once you start bolting on the right bits the engine really flies. With the Zetec you have limitations as the engine is undersquare, the bore is smaller than the stroke, the valve and port sizes are smaller so you will never achieve the figures of a Duratec. Be careful of chasing power you don't need. I ended up with 260bhp in my Duratec and hardly use it. I'm de-tuning it to make it more suitable for the road. Anything from 190 bhp up is going to be fun. A tractable 230 bhp in a road Zetec is probably the top figure I would be aiming at. I was speaking to Geoff Wilson at HWR as one of his customers ordered some bits from me to put on his engine. We got chatting and both agreed that too much power on a road car would be a hindrance in a light vehicle. Racing and track use is another matter, you need all the power you can reliably get if you want to go past people on the back straight at Snetterton. Last night I fell asleep early and woke up at 1 am. This time I was working out BMEP figures for the 2 litre. It is generally accepted that around 230 lb brake mean effective pressure is in the right ball park for a race engine. When we got 185 ft.lb. of torque on the dyno Dave Walker commented that I wouldn't get much more than that from a 2 litre. So that got me curious. The BMEP figure for my engine is 227 lbs. so pretty much there or there abouts. You could get more but it would cost more money in development. What I am thinking of is an engine that isn't difficult to port and doesn't need big valves but has components that work in conjunction with the head. I have sold kits of my parts to professional engine builders abroad who have got exactly the same power outputs as the engines I have built. What I am thinking is kits that contain everything you need to make a 280 bhp engine with a stock crank or a (I'm guessing here) a 295 bhp engine with a steel Raceco crank. I even thought of modifying the stock crank but at the end of the day I don't think it is worth spending any money on. Better to do the job right. Also had a half hour conversation with the man that is going to design the new crank. Lots of little details and intricacies to discuss. Although the 88mm crank will form the basis of the 2 litre one it needs a complete re-design as it is doing a different job, different journal sizes, rpm, etc. When I sent the drawing of the 88mm crank to crank manufacturer they called me up to see if they could make some changes to the drawing to make it easier to machine. I told them that I had just paid £800.00 + VAT to someone to design it I didn't want it changed in any way. As a lot of the Duratec parts I have made have been copied I have not shown photos of the 88mm crank to anyone. Some of the customers who have them in their engines haven't even seen it. I have decided to concentrate on the 2 litre from now on. I've done almost 2.5 litre engines and everything in between. Big engines are OK for rally cars but have no real place in a Seven in my opinion. Unless you like wheel spinning all the time Also the 2.3 engines are no longer available and have been replaced by a 2.5 with a 100 mm stroke. Not exactly a race engine. More like a tractor. Not interesting to me. The 2 litres are also readily available second hand so it makes a lot more sense to cater for these. Looking forward to these new developments. I have been treading water for the last couple of years. Not building engines for a living has taken a lot of stress from me and allowed me to do other things. I still enjoy the development work though. I wonder about airing my thoughts in public and whether people find these things interesting or not or just the ramblings of an obsessed bloke. From a selfish point of view writing it down helps me put my thoughts in order though.

Thanks Dr. Slotter for the additional information. Nice to hear from people in the know who are actually involved in these things rather than the second hand snippets I get. Any stories or anecdotes you can share? I had a friend who now works for Lotus that used to work for a company called Scott Gibbin. They did testing on on the Cosworth Sierra turbo engines. They used to get the engines up to temperature and at maximum revs dump 200 gallons of cold water through the cooling system to see if they could make the head gaskets pop. Done any similar nasty things to engines in your work? The crank on a 2 CV is a pressed together affair. A one piece crank would be an improvement but what is likely to limit the rpm capacity to rev is the cylinder head. Anyway going the one piece crank route is likely to be expensive. If it were my engine I would look at what can be done to improve the standard engine. I'd be looking at something like 50 bhp per litre, so around 30 bhp perhaps? I had a Guzzi V50 when I lived in Shepherd's bush in the early 80's. I would commute to work to my job as a workshop manager at a place called Motomecca in Clapham. I thought it would be a good idea to tune the little Guzzi. I ported the heads and had a cam ground, I think I even stuck bigger carbs on. The result is the the bike had no bottom end, wouldn't tick over and was generally a pig. I had to raise the float levels in the carbs so it would run at all. No gas velocity at low rpm. The one thing it did do well was rev. The power band started at 6,000 rpm and went on to 10,000. I did my own form of destruction testing every morning over Wandsworth bridge giving it the berries knowing that if I blew it up I could get someone from work to pick me up. Never did manage to break it. I later sold the bike to a guy on the Isle of Man who stuck a standard cam in it and and went on to do many miles more. The moral of the story is don't stick the cam profile for a 1,000 cc engine into a 500cc one. I've done a lot more work on small cylinder capacity engines since and have been more conservative on the duration figures. I'm really interested in having a look at the 2CV to see what sort of potential it has. Maybe a few of you 2 CV freaks could get together to fund the project?

Interesting stuff. Jeff Wilson has a good reputation. Never heard a bad word said about him. 190-200 bhp out of a 1600 cc engine should be good fun to drive. My old 1800 Zetec had 189bhp and in retrospect for a general purpose, do everything, car it was the best I had. The obsession with Duratecs made me change, but 190 bhp is the start of the fun zone in Caterhams in my opinion. Look forward to hearing your driving impressions Garth.

😬 Actually the industry norm is 1,200 hours at full throttle I think. The Moto Guzzi engine in question was a development engine, not one that was due for production. Two hours at full throttle is enough to have a strip down and have a look inside and see what's wearing. I saw one of my engines let go on a Schenck engine brake dyno in the late 80s. It was a 1,000 cc 95x70 experimental engine. It had been run in at 4000 rpm for a few hours. We were running it up to 10,000 rpm at full throttle and everything seemed fine. All of a sudden the engine changed note and the next thing I saw was bits of big end shell coming out of the breather. We shut it down as quickly as possible. The damage was not too bad and after a rebuild we ran it again a few days later. Turns out the 1mm squish wasn't sufficient at 10,000 rpm and the pistons had started touching the heads and knocked out the big ends. Increasing the squish to 1.2 mm solved the problem. Your 2 CV engine also has a 70mm stroke. Fancy revving that to 10,000 rpm? 😬

Mankee! Just the man. I wanted to talk to you about a couple of things. Pop over for a cuppa or a beer soon? I think whole Nissan touring cars were sold off at some point and ended up being raced privately. What I have heard is that they made more power when they had the rpm limit raised and had some additional work done. Quite a bit of time was spent on the dyno developing new exhaust systems.