Looking for some opinions on the positioning of the chargecooler pre rad. If making a change want to avoid it causing any issues for general cooling. Only considering it as have the clam off. Car has been borderline with temps getting to 98/99 degrees on track since moving to laminova for oil cooling, and hence I’m switching from the current large 50mm rad to a 50mm triple pass.
Currently I have the pre rad in the nose of the car, just behind the tow post, as seen here:
Cool air also flows past the rad and hence main rad gets some cool air flow
Minus points:
Warm air from the pre rad comes into the cabin interior via the vents
Air escapes past the rad, perhaps meaning it isn’t quite as effective?
Although relatively large volume of coolant in the rad, has small surface area to the oncoming airflow.
Trying to decide whether to change it to the pro alloy pre rad instead. This is bolted to the main radiator core in a similar position to where the air con rad would normally be.
Plus points:
No more hot air coming into the cabin.
Air can’t escape past the rad and hence should have maximum cooling
Minus points:
I’m worried that this will make the main radiator less effective.
Worried that there may be some heatsoak from the main rad into the charge cooler rad.
What say the collective wisdom on here?
Ideally I’d have temperature information for the chargecooler as it is just now to help me make my mind up. All I can say is that the car always goes well even after a long track session so no reason to suspect that there is any issue. Would be a shame to change and then have problems.
I’m currently erring with leaving it as it is and running some ducting to the air intake in the crashbox to resolve the cool air to the cabin issue that way instead.
Why not reuse the oil coolers for the charge cooler?
My biggest issue using the Proalloy charge cooler pre rad was engine temps, I reckon most of this was caused by still having the restrictive air con rad installed.
The other change I made was to seal all the possible points that air could escape from rather than going through the radiator stack, this made a couple of degree difference to engine temps
What’s the rationale behind your comments Tim? That would give a stack height of about 95mm without the fans. There’s got to be a limit on how thick you can go without it becoming overly restrictive?
I’m not hot on fluid dynamics.
The rad I’ve been using is already huge, and the 50mm triple pass is as big as is available off the shelf anywhere. (Thanks Dave).
My concern is basically what Ade is saying that if you put the pre rad in the main radiator stack you restrict the airflow for the main rad.
Ade, the oil coolers wouldn’t provide the same volume of cooling as the current pre rad. Had previously considered running them in series, to give more overall volume, but don’t think its necessary. Also have some cheeky plans for a GT3 front clam install, so that would make the oil coolers redundant.
I was thinking to run them in series, if you can take 5 degrees of the water temp for each oil cooler rad you use that is 10 degrees the centre charge cooler rad is not trying to shed, this in turn will mean cooler air going to the main water radiator, surely that has to help?
Ok so this is me writing without thinking too much (as usual )… With the S1 I was thinking about ducting large hose from the crash structure through the (now accessible) sill to the engine compartment but not for your reason obviously. In your case, should you go for that respray do a Gav, cut the clam and bang it in the rear (211) with a couple of fans attached Frankie stylie maybe. Slightly extreme.
Will
I ran pretty much like your car but with a pro alloy charge cooler rad at 32mm thick with no ac
I had same issue with temps.
I added a small rad into the heater circuit positioned in the left front corner where the oil cooler used to live. This knocked 8-10 degrees out of the coolant lemp
Nope!!! I bought the correct rad from Lotus!!!
Current Elise SC has a charge cooler rad that sits in the N/S/F corner
Bolts straight into where the oil cooler was and the pipes are a similar size to the heater pipes (I didn’t have a heater) If you put it in the outlet side of the heater you will remove heat but still be nice and toasty if need be!!
This is something I was thinking of…using the 2-11’s twin front oil coolers as chargecooler rads. (Assuming a move over to a laminova oil cooler set up) Give the oil coolers a damn good flush out and use them to cool the inlet temperatures instead of pulling the front clam off to fit an extra radiator.
I’ve always wondered if the twin oil coolers cool the engine oil down too much and if the laminova is a better option?
The twin oil coolers are actually very good, I asked proalloy to fit me some upgraded ones once, their answer was not to bother as the ones there are very good anyway and there would be little benefit!
Id go with two rads in your original oil cooler position and use the biggest water reservoir you can fit in. Mine in my S1 was almost 8 litres from memory.
Your triple pass rad with no obstructions will do the job of keeping your engine coolant under control.
)… With the S1 I was thinking about ducting large hose from the crash structure through the (now accessible) sill to the engine compartment but not for your reason obviously. In your case, should you go for that respray do a Gav, cut the clam and bang it in the rear (211) with a couple of fans attached Frankie stylie maybe. Slightly extreme.