andy couchman

Need to change the oil on the crossflow this winter (1.7, 150bhp, mainly road with the odd track day and sprint). Opie's website suggests a 5W-40 synthetic oil - is that too thin though? ISTR that if you go too thin the engine burns more oil. In terms of brands, the range is from Gulf at £20 to Castrol at £60. Anyone any views - the Gulf looks to be very inexpensive while Fuchs and Shell are around £30 for 5 litres. Anyone any views/suggestions/recommendations? Thanks all. Andy

Thanks all and yup spoke to Avo this morning and they're sending me new rosejoints at just £7 each, which sounds pretty good. Will need a big vice or press to get the old one out apparently but, once the dampers are off the car, can easily get that done at local garage of necessary. Andy

Brilliant - thanks Keith. Andy

Worth replacing the scuttle rivets with rivnuts and stainless fasteners too. That makes the scuttle so much easier to remove if ever you need to in future too. Andy

Couple of things to sort on the 7 over the winter: My live axled car runs Avo ali dampers and the bottom rosejoints on the rear dampers need replacing. Anyone done this and would you recommend buying replacements from Avo or from elsewhere? I need to replace the main (copper) brake lines. Is it feasible to do this yourself? If so, guess I'll need a flaring tool plus the pipes themselves. Easy or difficult and best left to those who know what they're doing? Thanks all. Andy

Just remembered a couple of other things: - delete reversing lights. Carry a torch (lightweight one of course) - delete the high intensity rear lights and replace with one small red FIA rain light as used on formula cars - put the number plate on the O/S rear wing. Delete the number plate light. Instead cut out trhe bottom of the rear light and replace the red plastic with clear plastic. Voila (that's yer actual French) you have a much lighter number plate light - drill holes in the red plastic engine cut off key and remove its shrouding. Fits in your pocket easier too Andy

A mate of mine has run his Porsche Boxster for five years now with a lithium battery (in summer) with no issues. Other possible weight losses: - horns (reduce from 2 to 1) - windscreen, wipers and washers (or just empty the wash bottle if it's a dry day. - rubbers from brake and clutch pedals and drill the pedals (done neither myself - not brave enough!) - carpets - remove the tails from zip ties! Incidentally, presumably you have told your insurer that you have removed the cat? Andy

I recently bought a copy of Carroll Smith's excellent 'Drive to Win' book, only to find when I got it home that I already had a copy. It's softback and was published in 1996. It's in very good condition and I'd like to swap it for one of his other books - either 'Tune to Win' or the 'Nuts, Bolts, fasteners and plumbing handbook' (which I think may also have been published as 'Screw to Win'). I already have the Prepare and Engineer to Win books. Anyone like to swap? Thanks. Andy

Maybe try two cars - one with standard and one with lightweight flywheel and feel the difference. We often talk glibly of a car with say 200bhp and forget that will only be at one particular point (pretty high up) in its rev range. Most of the time - especially in a road car - the engine will be accelerating or decelerating. So at half max revs you may have a 100bhp engine, maybe less, maybe more. We want it to pull as hard as possible (e.g. to nnot slow down going up a hill) and also to increase speed as quickly as possible (when accelerating). Max power is perhaps really only relevant when running flat out or just before changing up to the next gear. My understanding is that a lighter flywheel in effect produces the least resistence to an engine trying to speed up and so improves acceleration and the car feels faster. That's how it feels. The downside is lumpier idling - less relevant to us. At lesat that's how I understand it. So, for a road car, do we mainly want torque rather than max bhp? Andy

Yes, crossflow cars should command a *whistle*premium. That looks to be a very quick car too - with its' 17 litre engine... Good luck with the sale - nice looking car. Andy

Have it on my car and would also recommend it. Andy

A mate has one in his Boxster Sptyder. Porsche recommend you don't use it in winter but otherwise it looks to be fairly 'normal'. Mega expensive and is it much of an advantage of say an Odyssey? Andy

Unless I've misunderstood... the new rules will mean 'new' list 1B tyres will not be road legal. That means a roadgoing car may not be driven on them - you'd have to trailer the car or else change tyres when you get to an event. 'Old' list 1B tyres will presumably be OK until they have worn out? What about 1A tyres that have been treated to make them softer. Illegal for competition purposes? Does sound like a mess but can also sympathise with the MSA - it cannot condone illegality and shurely roadgoing cars should be road legal when they compete? Help!! Andy

I'd talk to Kendricks too. From memory Clive Kendrick was a British Hillclimb Champion in a Caterham (not sure if it was live axle or De Dion). They will certainly be aware of the issues and, as others have said, your symptoms do sound like oil surge. A well set up Ital axle is lighter than both a Ford axle and a De Dion (so giving straight line and cornering advantages) - but it has its faults and they include not liking 200+bhp (especially on very sticky tyres) and appearing not to like kerbs as much as a DD would. But countless race cars have run Ital axles for years without too many problems and many of us are happy to run them. A DD is not better IMHO - only different. And I get a certain bizarre satisfaction from admitting that my car has an axle from a Morris Ital! You can throw money at them - lightening the crossbrace by drilling very big holes in it, changing the open diff to a Qualife ATB and replacing the halfshafts and even converting to disc brakes (the pukka Rakeway full kit) but those are all optional rather than necessary. Good luck in getting it sorted and glad you enjoyed Throckmorton. Andy

Any more views on the Redline rose jointed A frame? Seems like a neat solution - any cons as well as pros? Andy

Bags arrived. Thanks Jonathan Andy

I used double glazing rubber strip. Compresses down nicely and fills any gaps. Andy

Thanks Dave. Can I just check I've understood this? Air enters the nosecone through the normal intake. Air flowing above the radiator goes into a sealed 'box', where it goes through an air filter and is then piped (two hoses) into another sealed box on the outside of the bonnet and thus into the trumpets? Are these short or longer trumpets? Whatever, it looks very neat! And if you could show some more pics that would be even greater! I feel a project coming on... Thanks all. Andy

I'm Jenvey'd too and run a 244 plus forged pistons. Power is just under 150bhp on a very honest RR (about the same as when on carbs) but the engine is a lot smoother throughout the rev range. I'd be interested in any pics you have of the airbox Dave - I just use foam filters and the car is noticeably noisier on the intake side than it was on Dellortos. Have thought about making an airbox but, quite honestly, not sure where to start! Thanks. Andy

Also check that the carbs are not too tightly attached to the manifold. I had similar problems with my car years ago - the carbs are supposed to be quite flexibly mounted and I had simply done up the nuts far too tight, resulting in over-compressing the rubber washers. Good luck in getting it sorted. Andy

No timing belt but I once had similar symptoms - engine turned over but valves did not open. It turned out the Woodruffe key holding the front pulley onto the crankshaft had come adrift and as a result the cranksaft rotated but the cam didn't... Did some (non-fatal) damage to a piston and we had to replace a bent pushrod but we were very lucky, especially as this happened at around 6,000rpm while on a rolling road. On a crossflow the valves go straight up and down in the cylinder head, so even if hit by a piston, damage is likely to be minimal to all parties (usually...). One of the joys of this great old engine! Hope that whetever it is, you can get it sorted quickly and inexpensively. Andy

Mechanical pump has a lot to do to so will need a lot of (low speed) churning to get fuel through. Maybe take the plugs out and churn it over on the starter until fuel comes out the pipe? Alternatively can you dripo fuel into the flat chambers in some way? Good luck! Andy

8s will also give you a wider rear track, which may further affect things. Oh this is too complicated! Andy

I think that, logically, understeer should increase (in the dry). For cars that already understeer (K series?) the effect could be increased, whereas for cars with a more oversteery characteristics it might introduce understeer or reduce oversteer. In the wet, all bets are off... Anyone tried both routes? My crossflow runs one set of 6s all round and one 6s and 8s and am planning to go to two sets of 6s and 8s so if anyone fancies a swap from a pair of their their 8s (Caterham 8 spoke anthacite) to my 6s, do shout! Andy

Interesting - thanks Jonathan. Looking at the Meredith effect (incidentally, can't see why antifreeze makes any difference to the effect - and what about Evans!) If you run your 7 with the cooling fan running (regardless of temperature), given that some/much/most of the air exits through the bonnet louvres, would that create any thrust effect? As the fan has to be driven through the battery, which itself is powered by the alternator, which in turn absorbs some engine power, would you get the best effect if on needing maximum acceleration or speed you: 1. Switch off the alternator. 2. Switch on the cooling fan. Or would the losses mean that the effect would at best be negligible? I'm not an engineer so may just be talking through what I should be sitting on... Andy