33 replies to this topic

[danyeates]

Why is it the Pro-alloy charge cooler has a pre rad that sits underneath the engine radiator? My dad has a PACE charge cooler on his VXT which has a small pre rad in the front grille. Similarly, Thorney’s charge cooler system features a small pre rad in the front grille. Im not trying to say one system is better than the other, just trying to get my head around the reasoning of making different systems. As I understand it, the idea of the charge cooler is to get the induction temperature as close to the ambient temperature as possible. So, wont having the charge cooler radiator, next to/under the engine radiator cause it to heat up? The engine radiator is constantly up near 89 degrees Celsius. The engine fan rarely comes on unless stuck in heavy traffic on a hot day, so the additional fan isn’t going to do much unless it’s switched independently. Even then, I would expect the front mounted radiator to perform better. Am I right in saying this? I haven’t read much about the Thorney’s charge cooler, or the PACE one my dad has. I am looking at maybe putting something together myself for my new car (will disclose more later!) I have a friend who makes a lot of charge coolers and intercoolers for the Ford RSOC. One other question, why is it that the Thorney charge cooler retains the intercooler but none of the others do. If the original intercooler is retained, where does the charge cooler live!?

Edited by danyeates, 02 July 2007 - 11:14 AM.

[Thorney]

We've fitted over 30 charge cooler kits and the same identical unit runs on my race car with over 330bhp on tap and intake temps have never been an issue as a result. We keep the standard intercooler as Lotus did an excellent job of it (they went through 7 different designs) it works better than anything and intercoolers work well in conjunction with CC's

[danyeates]

Thanks John, I am only going off your photo of the kit but I assume your pre rad fits in the front grille. When you fit the charge cooler and intercooler, does the induction flow through the intercooler first or charge cooler? Where do you mount the charge cooler?

[JG]

Do you mean 'Which'?

[danyeates]

Have been looking at this design:

CLICK

Found THIS very useful.

[Winstar]

As I understand it, the idea of the charge cooler is to get the induction temperature as close to the ambient temperature as possible. So, wont having the charge cooler radiator, next to/under the engine radiator cause it to heat up? The engine radiator is constantly up near 89 degrees Celsius. The engine fan rarely comes on unless stuck in heavy traffic on a hot day, so the additional fan isn’t going to do much unless it’s switched independently. Even then, I would expect the front mounted radiator to perform better. Am I right in saying this?

Firstly the pre rad sould see none of the heat from the main cooling circuit as the air flow passes though it on the way to the main rad, even when staionary there's a pocket of air to insulate the prerad, the only heat transfer would be a neglagable radiation.

Secondally a front facing cc rad would be more effective buy only if if could be of the same surface area, with the pro alloy version then there is a huge surface area and a good airflow.(i'm sure Alex O will be along soon to explain all)

If you retain the std IC than this will be in series before the CC as IC work best with a large diference in fluid stream temps, an advantage of removing this is that there is then additional engine bay cooling through the offside ear, rather than the heat rejected from the IC being fed into the engine bay.

[danyeates]

OK great, clams are off the car now so will look into measuring up and finding space for everything. Are you therefore suggesting that the larger pro-alloy pre rad method is better? What you say does make sense. Why is it that some charge cooler units are countercurrent and some aren't? Surely if it's best to make them countercurrent (like a true heat exchanger) why aren't they all like it? I have read some websites recommending the water flows the opposite way to the air and some that recommend it flows the same way!!

[oblomov]

I looked carefully at both designs before I opted for the Pro Alloy kit. The Pro Alloy pre-rad isn't just one that conveniently matches the size of the grill apperture, it's a bespoke piece of kit designed specifically for the VX220. Where the Pro Alloy kit has the advantage IMO is in the huge size/volume/surface area of the pre rad and therefore the volume of water it can cool; and the size of the header tank where the coolant circulates. The system carries 13+ pints of coolant . The Pro Alloy CC unit itself is massive and when I got it, at first I thought I had made an error and fitting it must be a rear clam off job, but in the event it just a very snug fit. I was looking at one of the earlier charge coolers the other day on an NA VX with a turbo engine in it . I've no doubt it does the job, but you could look at the Pro Alloy unit as the next step forward.

Edited by oblomov, 02 July 2007 - 12:49 PM.

[Thorney]

Intercoolers are 'better' at cooling intake temps when in direct airflow and charge coolers are 'better' when airflow is restricted. So if you have some airflow it makes sense to maximise the IC use of it. The standard IC is excellent in every way (Lotus do know a few things) so we keep it. We then mount a charge cooler in line (ie straight after the IC and just before the intake) so the air is cooled twice in quick succession, hence we've not need to change the system one bit for the race car, it really is over engineered. Because we do this we only need a realtively small front prerad to cool the water which means weight is reduced as well. Ours doesn't need extra fans again for this reason. Keep it simple, prove it works is my motto

I looked carefully at both designs before I opted for the Pro Alloy kit. The Pro Alloy pre-rad isn't just one that conveniently matches the size of the grill apperture, it's a bespoke piece of kit designed specifically for the VX220.

I assume you're not referring to ours, it was custom designed for the aperture. I'm sure both work well, I personally don't understand the idea of losing the IC to make a bigger CC as IC's work more efficiently and the VXT one is proven to be brilliant at its job but horses for course I guess. We also had a long look at weight, fans, electrics etc all add to it (as well as more things to go wrong).

Put it this we, we don't even runa nromal fan on the race car, it doesn't need it, the CC set up does it all.

[danyeates]

John, I like the sound of your system. Do you sell the heat exchanger on its own? As mentioned, I plan to fabricate everything else. One more thing - where do you put it? Behind the intercooler?

[oblomov]

I looked carefully at both designs before I opted for the Pro Alloy kit. The Pro Alloy pre-rad isn't just one that conveniently matches the size of the grill apperture, it's a bespoke piece of kit designed specifically for the VX220.

I assume you're not referring to ours, it was custom designed for the aperture.

Sorry, John not very clear on that, what I meant was if you cobble your own charge cooler together, that's what the pre rad will be.

[Thorney]

Its actually a pretty simple install. CC fits underneath the rear clam at the right hand side, there are pipes conecting it to the IC then down the right hand side sill where they attach to the front prerad. At the left hand side of the engine bay sits the resvoir with the pump underneath. We've sold qyite a lot mail orde rnow so its pretty easy to install, rear clam doens't need to come off and its a fit and forget system.

[Guy182]

pics showing Pro alloy chargecooler (check out the neatness of the welds and the bespoke components)

http://www.guysleema.../v/vxt/cc/day2/


this taken from another thread:



Lower line TMS software with TMSchargececooler/standard intercooler
Middle line Courtenay software/VXRinjectors with TMSchargecooler/standard intercooler
Top line (my car) Courtenay software/VXRinjectors with Pro alloy chargecooler

mine and tonys car (i think it was tonys) there both had exactly the same map put on, same spec engines, running a held 17psi i believe

question is.. is this difference in power down to the smaller pre rad or the extra piping going through the chargecooler then through the intercooler restricting the flow?

forgive me if im wrong Thorney but in another thread you said you was suffering major heat problems with your race car?


as regards inlet temps, mine has never seen more than 32 degrees during hard driving (standard intercooler was 76)
round cadwell out for lots of laps in Alex Os i saw his crept up to 40 after a long session but soon dropped straight back down to 30.

Edited by Guy182, 02 July 2007 - 01:56 PM.

[danyeates]

How would a car benefit from having something bespoke? For instance, large pre rad like the Pro Alloy one (which looks quite simple really), charge cooler and an intercooler? My initial worries were that the air flow would be greatly restricted through the intercooler and charge cooler - as you said.

[Guy182]

quote off Race report.. ''Engines get hot for three reasons; running lean, poor ignition timing or lack of airflow, we’ve confirmed that fueling and timing are both spot on but engine bay temps are still rising to absurd levels '' maybe it would help if you removed the intercooler so you have less hot air running round the engine bay. dan, i dunno what you mean really but end of the day those blue and green lines on the graphs are identical spec cars, only difference being mine has pro alloy and tony's has TMS CC's, does anyone have any pics of the pipe that goes from TMS heat exchanger roudn to the standard intercooler?? im not fussed what you buy really.. im nothing to do with the companies and i paid full retail price for mine the bigger the pre rad the better.. the spal fans on mine are wired to a switch in the cubby hole so when i pull into the pits i can flick the fans on and keep the chargecooler temp down when theres no air flow. also the rad coolant jumps straight back down to 85degrees

Edited by Guy182, 02 July 2007 - 02:05 PM.

[cyberface]

John - with your chargecooler setup you need a small rad at the front of the car. Is this vulnerable to stone chips / nails / etc. and does it hang down below the usual splitter / numberplate height? I ask this because I have a lot of speed bumps my way, and also like to drive fast on the Kent twisties, which can bump about a bit... Is there a warning light / gauge to notify if there's loss of coolant as well (for example, if a nail were to penetrate the CC radiator)? I've had radiators punctured before. Cheeers!

[Guy182]

you can see it here cyberface:




it sits within the mouth.

prob best to remove V as per pic to aid flow to it as the V would cover the cntral 1/3rd ish

Edited by Guy182, 02 July 2007 - 02:13 PM.

[danyeates]

Never had a problem with my dads charge cooler pre rad getting hit by anything. Is PACE and mounted in the same place. It fits inside the front clam, nothing hangs below. Thanks for the info Guy. I like the idea of the larger pre-rad, it was just questioned by a friend of mine as it was so close to the engine rad. I also like the idea of having a switched fan. Is this for both fans or just one (ie is one still controlled by a thermostat in the engine cooling?) I will end up making a pre-rad, im just trying to find out what method works best. That graph is very useful, thanks. Will go away and have a think now!

[Guy182]

winstars an engineer, id take his opinion the subject the pre rad doesnt come into any contact with the radiator, theres an air gap between them to, also the pre rad is BELOW the radiator so the cold flow of air hits the pre rad THEN through the radiator., the radiator end caps sit close to the pre rad but thats about it. my fans are both switched, and also controlled by engine automatically (just T'd the switch into the fan supply)

[cyberface]

Cheers Guy - it's a different colour to when I last saw it! Best place for it, however will need as you say removal of the V, and also some decent wire mesh protection. Anyone here had a pre-rad punctured? These cars sit pretty low, and I thrash around country lanes and the front of my car looks like it's been shotblasted