skydragon

Boys, boys, boys, I wasn't letching over Ms Lusardi, merely having a polite and well humoured chat regarding my 'memories' from 1980's regarding her, ahem... 'contribution' to British popular culture 🥰 🥰 🥰 🥰 😬 😬 Edited by - skydragon on 15 Mar 2013 15:52:19

Thanks Mr B

My 2p's worth. I'd go to DVA and seek his advice. I'd guess that porting your existing head and adding an Emerald ECU would get you the power increase you want (??). Verniers may be recommended as well. fwiw - Unless you want to sell your car to CC (which you may) I'd forget trying to fit in with the CC model versions/specs and just upgrade it as best suits your needs/budget. eg. Mine has been taken from a 1.6k roadsport to a 'R380'...does it really matter what badge it has on it, as all caterhams are basically the same but with different bits bolted on (except the CSR of course).

Thanks, sold to jingars

Set of 4 x 'blue' injectors from a low millage K-series, have 0280 156 024 number on them £25 inc P&P

The flow rate, is the maximum fuel that will be flowed through the injector when on full duty cycle. ie, when the ecu is opening the injector as much as it can. Remember the maximum fuel flow you've stated would only be if the injectors were mapped to be on 100% duty cycle, which they shouldn't be ideally. With that in mind, it looks like your fuel pump would be ok. HTH Edited by - skydragon on 7 Mar 2013 12:55:04

Mine (K-series with TB's and CC dry sump with Pace tower tank) has the rear vent blocked off and the front vent run back to the 2nd connector on the Pace tank. The centre top connector on the Pace tank then feeds into a remote catch tank. An outlet on the catch tank then feeds (via a long pipe fed down underneath car) to open air. Good simple system and has worked perfectly for 2 years and is system used on many other cars. Have a look at this photo here Edited by - skydragon on 6 Mar 2013 13:43:26

What's the score with getting a replacement, or are you taking a break for a while?

If you can afford it, a Emerald ECU, some verniers and a rolling road session would be the best bet I guess.

I think the engine limiter comes on at 7,600rpm on a MEMS ECU's K-Series and it makes max bhp at this point, so If I were you I'd set the shiftlight to around 7,200rpm

Did you get it hot enough for the PRRT to allow water to flow through the rad? yes....but what I've now realised is that the first time this happens after halting the car (when you've run the car up to temperature, but the radiator is stone cold from the airflow whilst driving) is that the main coolant temperature has to climb to near 100 DegC before the PRRT stat will open and let coolant through the radiator. I hadn't reckoned on the fact that the cold coolant in the radiator and bottom hose (which connects to the PRRT) would cool one side of the stat and raise the point at which the PRRT stat will open, by some 4- 5 degrees. Once coolant has flowed through the radiator once and the cooling fan clicks in, everything is ok and the fan cycles on/off ok, as the bottom of the radiator now never gets cold enough to affect the PRRT stat as it initially does. I don't know whether this will happen quite the same when the weather is warm and the radiator isn't quite as cold.

Dad - 😬 😬 - I did drive my seven at the weekend, for the first time this year....and this is what caused this whole damn question, when the bloody PRRT wouldn't open cause the bottom of the radiator was stone cold (i knew I should have left it in the garage ) I'm not saying a PRRT is better... because mine isn't working as I'd like it to Why won't the damn thing work? I'd go back to your old temp sender on the rad for the fan switch and fit a manual override so that if it fails you can simply flick a switch on the dashboard sounds like a plan

When you have a remote stat fitted in the top hose, do you still have the old bypass hose fitted between the water rail and the engine coolant input, or is the old bypass hose blanked off at each end (as it is with a PRRT install). ie. Do you have two bypass hoses with a remote thermostat install, or just the single bypass hose, from the remote thermostat housing down to the bottom hose (via the expansion bottle piping)

Agreed that a thermostat will typically open slowly and close even more slowly, so it isn't a 'perfect' regulation device by any means. My comment wasn't regarding how fast the thermostat opens, but about the difference between how a PRRT and a remote stat works. With a remote stat, when it (slowly) opens it will slowly push cold coolant from the radiator bottom hose up into the engine. On the way up the piping, the cold coolant will mix with the hot coolant from the (relatively slow) small bypass piping. The small bypass piping is necessary to ensure there is enough 'back-pressure' so that coolant will still flow through the thermostat (when open) and through the radiator. With a PRRT the bypass is far larger diameter (x 3?) than with a remote thermostat, so there is a far faster flow of coolant around the engine - and the cold coolant is mixed in the PRRT unit itself. To get around the problem of having a large bypass which might effectively rob the radiator of any flow when the thermostat opens, there is a pressure valve in addition to the thermostat which provides some backpressure when the engine is cold and more backpressure when the engine is hot (and the radiator is needed). So in theory the PRRT should provide a far-faster and more temperature-constant flow of coolant around the engine, which is good. The remote stat solution is in some ways a far easier solution. There are far less pipes involved and it could be made more cheaply than a PRRT. I guess that Land Rover felt a high-flow bypass was the key requirement for the K-series engine when they designed the PRRT? I think one possible advantage of the remote thermostat being located at the exit of the engine, is that I don't think it will be affected by cold radiator temperatures like a PRRT or normal thermostat can be (??) It's seeing the input of the radiator, not the output.

I was thinking of something more modern looking as a stylish racing/sports design. (just my 2p's worth though)

Aero body to drop onto the S3 chassis Agreed *thumbup* Although it might be difficult to engineer properly (?) I reckon a decent shell body that fitted onto a S3 chassis as a semi-permanent fitting would be a massive seller for CC and a good additional revenue source. Produced in a stylish design and at a sensible cost, I reckon it could be an attractive option for many seven owners. I mentioned this to CC a couple of years ago (admittedly to only a couple of staff) and judging by their response they presumed I was on crack-cocaine 😬 I put it down to their lack of vision and the fact they were over-excited about SP300, which is of course a far, far, better business idea 😔 😬 😬 😬 I'm surprised no 3rd party company has taken this up and made a 'body' for a 7. It could be an 'easy-win' for someone (??)

With a PRRT the coolant entering the engine should be at approx 82 Deg C - why - because cold coolant is bled and mixed into the bypass loop (the main circuit on a PRRT) when the PRRT thermostat opens up and allows cold coolant from the radiator bottom hose to bleed into and mix with the PRRT bypass loop. The thermostat won't work as a perfect device admittedly, but this should ring roughly true if everything is working as intended. The advantage being a very fast coolant flow rate around the engine as the bypass loop is significantly larger than normal and a stable temperature due to the PRRT bleeding coolant into the bypass loop only when needed. This presumes of course that the radiator will provide a continual source of cool coolant to enable the PRRT to do it's job, but the actual coolant temperature isn't determined by the radiator. On a remote thermostat, I'd have thought the coolant temperature entering the engine would be lower than the thermostat temp, as the coolant temperature entering the engine will be in part cooled and defined by the efficiency of the radiator. The hot coolant coming out of the engine is fed via a narrow bypass pipe back to the engine input and also when the coolant coming out the engine is hot enough to open the thermostat, coolant is then allowed to flow through the top hose of the radiator and back into the engine's input, where it mixes along the way with the bypass loop coolant. I'd have still thought though, that the coolant entering the engine would be 82DegC or lower due to the fact it's been through the radiator. eg. If we presume the coolant exiting the engine is at 86 Deg C and the 82 DegC thermostat is wide open, then the coolant will be flowing through the radiator, which will cool it down. I was going to fit a remote stat originally to my car, but i liked the idea of a PRRT constant temperature system. ie. with a remote stat, when the thermostat opens you then get the contents of the cold radiator fed straight into the engine, something a PRRT should avoid. (in saying that my PRRT system doesn't seem to be behaving as intended right now )

Totally agree Stu. It may be a case of trying to control the raditor fan, which should be actuated ideally by the temperature of the coolant at the top of the radiator, by using a temp sensor in the water rail is not a good idea. The solution is easy, by using the standard radiator thermostat switch instead to control the fan (although it would have been nice to be able to program on/off points). The more worrying issue is why the PRRT doesn't seem to work properly as a thermostat unless the radiator has warmed through first, causing an initial rise in temperatures when first stopping. This isn't causing any harm and mayby I should ignore it, but I'd prefer it to work correctly if possible.

The temp sensors are reading accurately. There is no difference between what my ECU is seeing in terms of temperature and what my dash display is seeing in terms of temperature. I'm 99.9% sure there is no airlock. I've just removed the PRRT unit and tested it in a pan of water, with a thermometer and it starts to just open at 82 DegC and is fully open by 88 Deg C. So the question now is, why does having the engine fan on stop the PRT thermostat opening? I guess it could be due to the cold radiator being right next to the PRRT unt (there is only approx 4" of pipe between radiator output and PRRT unit) and as such this cold coolant is cooling the PRRT down so it never gets up to above 82 DegC ? Looking inside the PRRT it has a jiggle valve in it, so there is always a very small flow of coolant through the radiator and through the PRRT thermostat. If this is the case, I think what is happening is this; - When I am travelling along at speed the radiator is not doing anything as it's output is very cold and it's preventing the PRRT from opening, even though the bypass loop through the PRRT is hot. When I stop the car and let it idle the PRRT doesn't open until enough hot coolant has bled through the radiator via the PRRT jiggle valve hole, to then allow the PRRT to open up. This time delay in the radiator warming through means the engine temperature climbs to near 100 before the PRRT opens up - but once the PRRT has opened up for the first time, the cooling fan cutting in and out doesn't then cool the whole circuit enough to stop the PRRT working ok whilst the car is static. The above situation means that I can't use the Emerald to control the fan. It also means that my car will heat up to around 98-100 Deg C before the PRRT will open up, for the first time - but if the car is stood still, the fan will then control the temperature and cycle it between 97 and 93 DegC. None of the above is doing any harm to the car....but when fitting a PRRT I had presumed that it would keep the temperature stable and not allow temperature fluctuations as above. I'm not sure the above would happen on a hot day - perhaps on a 25 DegC day, the radiator output would be warm enough to let the PRRT open and function ok, all the time??

John - But if the the bypass circuit is hot and above 82 Deg C, surely the PRRT should open irrespective of how hot/cold the radiator hose output is ?

My invoice is in the post 😬 😬 Glad we could help

bttt - any ideas?

Woahh a moment. *wavey* Are you sure that it's isn't just the water rail leaking!?! It's a common problem on K-series, where the paper gasket on the water rail fails and weeps, right where the water rail mounts onto the engine. Sometimes the coolant runs along the block, making it look like the coolant is coming from the head gasket, when it isn't. Simple fix is remove the two allen bolts holding the water rail on, remove the water rail and fit a new water rail gasket, making sure you don't overtighten the allen bolts when refitting. This is the gasket you need here. Of course I may be wrong, but it sounds strange that there aren't other symptoms.

According to this page here the grey version is the 82DegC version

I've a modded 1.8K with no heater and a standard grey Land Rover 82DegC PRRT fitted and up until now I've used the standard radiator thermostatic switch to turn the cooling fan on/off. I decided last week to wire up the emerald ECU to control the fan instead via a relay. All works ok from an electrical point of view....but there is a puzzling issue that I just can't understand...can anyone please assist? In the past, I've been used to see the fan come on with an indicated coolant temp of around 97 degC and go off at around 92DegC (measured on my digital dash and calibrated). The Emerald coolant temp and my digital dash temp are within a degree or so of each other....so wanting to match the previous settings as a starting point, I set the emerald ecu to switch the fan on at 97 and off at 92. I've described below what is now happening....and I'm confused *confused* I start the car and let it warm up. The outdoors temperature today was approx 9 Deg C. Eventually the coolant temp gets to 97 DegC and the emerald switches the fan on - all ok. However at this stage the radiator core/bottom is still stone cold and what now happens is, the fan continues to blow, whilst the coolant temperature continues to climb to 100. In effect the PRRT never opens and due to this there isn't any coolant flowing through it (?) and as a result the radiator actually does nothing to cool the car even though the fan is on. If however, I disconnect the fan for a moment and let the car warm up to around 97DegC and wait for a minute, the radiator then starts to slowly warm up as coolant flows through it (The PRRT has opened) - If I then reconnect the fan once the radiator core is hot, the fan will now cycle on/off controlled by the Emerald ecu perfectly ok and it controls the coolant temperature ok, as you would expect. Question is; - why does the fan coming on before the PRRT has first opened, then stop the PRRT from opening at all, even though the coolant in the bypass circuit is hot? - why does the PRRT seem to work all ok, if I first let the radiator warm through by temporarily disconnecting the fan and then reconnecting it. - I could try setting a higher switch-on point on the Emerald ecu, but that would then make the fan switch-on point too high. I've reconnected the standard radiator thermostatic switch and it all seems to work ok, but I'd really like to have better control of the exact fan switching points via the Emerald if possible. In some ways switching the radiator fan by measuring the coolant exiting the engine is not the best idea, because what you really want to do is turn the cooling fan on when the radiator itself is hot, not the engine. Any ideas?? Thanks, Edited by - Skydragon on 3 Mar 2013 19:55:16