Engine Temps....

Hi all -
I'm working on an electronic (Microchip) water pump controller at the moment as a few of us use the Davies Craig or similar electric water pumps and the supplied controllers seem a little 'un-suited' to GT40 arrangements, i.e longish pipe runs between rad and block.

So, the question, what temps are you guys happy with on your motors?

What temp before you 'gun it' ? What is the max you'd generally like to see? - What if you're running an alloy block - (prefer lower)??

I have a few pre-conceived ideas about the temps I'm aiming for and I intend the unit to be programmable, but any other advance feedback would be most welcome...

I also intend the controller to have some 'pre-emptive' logic to help with sudden unexpected changes and to be able to control the rad fan(s) too, to close the loop so to speak...

All responses greatly welcomed.:)
 

Howard Jones

Supporter
302 9.5 to 1 CR with alum heads. 5/8"dia hole in restristor plate in place of thermostat.

I like to keep it under 3500RPM's until the water in up to 170F and the oil at
180F.

Cold day less than 50F. Car will not come up to temp. Runs at about 160F both oil and water. Ya... I know this is bad but I live in California and it doesn't get cold.... and if it does I stay home. And.....it's sunny all the time and warm. Sorry....not like you guys back east, midwest, euros, etc.

Cool day 50F-75F, water temp, 180 Oil about the same.

Warm day 76F-90F water 190, Oil about the same.

Hot day 91F-105F+, water 200F, oil at about 200-205F

Track day, 6000RPM rev limmit, 20 min run, air temp 85F, water 200F, oil 210F

I have driven my car on one VERY hot day with air temps at 115F (no shit). Car ran at constant speed of 75MPH for 2 hours at 225F water, oil 230F, Air temp in cabin approx 135F, no AC, dried water soaked T-shirt in ten min's. I NEVER will do THAT again but car was fine.

I think water should be held as close as possible to 180F-190F with oil at about 190F-200F. This is based on 30 years of old wife's tails, but I've never heard of a damaged motor at these temps.

My car will hold these temps on most days unless I get caught in 1st gear creeping traffic for 20-30 mins or more on a "hot" day. With fans on in these conditions I will expect 210F water but the oil will remain at about 200F. I have not boiled over since I got the cooling system sorted.
 
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Paul, not wanting to pee on your bonfire but have you seen these on this this site :-

Delta Current Control

I have the fan controller on my car and it works very well, they make one that includes the waterpump aswell. May save you a heap of work.
 

Pete McCluskey.

Lifetime Supporter
Paul, I like the water temp to hang around 80c.My fan kicks in at 80c and I have never seen the temp higher than 90 and that was in bumper to bumper traffic on a day with 40c air temp.
 
Thanks for the input guys, all taken onboard. :)

And don't worry about my bonfire Paul, I like doing things my way and it gives me the opportunity to make it work how I want it to work, which may not be the same as another mfr dictates.
 
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