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So, in the recent race craft training day at Winton I had an coolant overheating problem. Up until then it only happened on a hot day, with the air cond on.

I suspect that it is caused by the dirty big front mount intercooler that I am currently using. The dimensions of the core are. 480mm wide x 300mm high x 70mm deep. I'm thinking that not only is the intercooler restricting the air flow to the radiator, it is also heating the air during the exchange process and therefore the air that the radiator does get is hotter than it could be.



I'm tempted to try a smaller intercooler, such as one from an SE. I'm not planning on trying to extract huge amounts of power from my turbo setup and therefore don't need such a big intercooler. Before I do this, I was wondering if anyone else here has any thoughts on this matter?

J

that intercooler is crazy big. is it the source of your problems? not sure.
but wouldn't you be better with something smaller anyway? a smaller cooler would be less laggy, right? one of those $100 little ebay coolers should do the trick, a bunch of guys are running those on na's and nb's.

talk to \"fuzzlet\" i understand he was having coolant overheating troubles with his turbo setup as well.

Got any ducting in the mouth? If not, you should try some - maybe it's just a matter of air passing around instead of passing through.

My intercooler is the size of the mouth of the car, but I've never had overheating issues since (aside from a slipping belt incident).

sabretooth wrote:Got any ducting in the mouth? If not, you should try some - maybe it's just a matter of air passing around instead of passing through.

My intercooler is the size of the mouth of the car, but I've never had overheating issues since (aside from a slipping belt incident).

I had to remove the black plastic support/ducting that sits inside the bumber as this and the intercooler would not fit. I suspect you are right about the air going around rather that through. I have been reading Corky Bell's maximum boost to get an idea of the IC size that I need as well as ways of ensuring that the air goes where you want it.

J

That would be the first thing I'd try. Don't bother dropping IC size. Put all the ducting back in and if possible even more the direct the air through both as much as possible. Otherwise upsize the radiator.

That be a Mitsi Galant/Lancer cooler made for a 2 litre motor.

I agree, enclosing the area may fix it.

How about something like this?



Begimake it, but I happen to know you can replicate it yourself if you have a sheet metal bender...

Boags

Mine heats up occasionally cat really put it down to a reason though
wont do it on the dyno etc

and most of the time its fine

If it is areally hot day then it will do it but it wont bubble over hot it just hits the high temp water alarm which is set at 100 deg

which i think is probably a little too low

I have got out and looked for water dripping etc and couldn't find anything

was there any water coming out and is it the standar guage you are using as a reference or aftermarket?

He's got a PWR 38mm radiator - which can cope with a shedload of heat - upsizing wouldn't help a whole lot, and is an expensive solution to the problem.

Bit of race tape, zip ties, etc and you should be able to stick some cardboard in as a test and see how she goes!

Juffa, are you happy with the ECU tune? Timing and air/fuel need to be less agressive as intake temps rise. A cold air intake makes a big difference this time of year.

sabretooth wrote:He's got a PWR 38mm radiator - which can cope with a shedload of heat - upsizing wouldn't help a whole lot, and is an expensive solution to the problem.

Bit of race tape, zip ties, etc and you should be able to stick some cardboard in as a test and see how she goes!

Correct as ever Geoff. I forgot to mention that I have a PWR radiator.

I'm hope to experiment with some ducting to see what effect it has. Of course the weather is much cooler now, so this may not prove all that much.
J

Boags'MX5 wrote:How about something like this?



Begimake it, but I happen to know you can replicate it yourself if you have a sheet metal bender...

Boags

Thanks Boags, had spotted that on the Miata turbo forum and the big forum. Would be a good idea......not sure it will work with the Vary Garage front lip (that I have not installed yet).

J

lowmiata wrote:was there any water coming out and is it the standar guage you are using as a reference or aftermarket?

There was a little bit of water loss on the day, which is probably involved as well.

In addition to the standard guage, I have the Link ECU hand controller whcih shows the actual temp in 2 degree increments. The standard guage doesn't normally move until the coolant temp hits 106c. It was well on its way to 'H' on the standard guage when I spotted it. I didn't have the Link hand contoller plugged in while out on the track so I am unable to say what the coolant temp actually was.

J

AL wrote:Juffa, are you happy with the ECU tune? Timing and air/fuel need to be less agressive as intake temps rise. A cold air intake makes a big difference this time of year.

Al, the Link ECU was tuned during more moderate temps, and could be a little aggresive. Having said that the knock sensor has not registered anything so far. I usually run on Shell or BP 98 octane. The Link ECU uses a temp sensor in the intake tract to monitor the air temp. When the air temp reachs 30c the ECU starts to pull fuel across all fuel zones and reduces the boost level. I could feel the reduction in boost while out on the track.

I do need to look at using some heat shield material to separate the air filter pod from as much of the engine bay heat as I can.

J