Cooling question for trackdays.
Discussion
My track Pheonix runs an Esprit S4 engine, No turbo but around 240 BHP, in shade temp of 37C, It has a triple core escort rad, the are ali fins down the side of the fan to stop hot air recirculating from the the engine bay to the front of the rad, and a craig davies water pump, wired in to work automatic, but with a manual override on the pump and fan, temp is fine without any extra venting at the back of the engien bay.
Roadcaptain! said:
gents,
what radiators are people using in the 7 type cars on trackdays, and do you find it essential
to have some kind of cooling vents in the bonnet?
also what sort of water temps are people seeing on track?
thanks.
You could spend a lot of money on a purpose built multi core rad. On the other hand, if you look at the space available and fit in the 'best fit' production car rad (preferably a modern ali with plastic headers type) you will end up with a proper solution that's cheap to replace. Fit a fan that goes right onto the rad (Spal or similar) and you're sorted.what radiators are people using in the 7 type cars on trackdays, and do you find it essential
to have some kind of cooling vents in the bonnet?
also what sort of water temps are people seeing on track?
thanks.
The amount of heat to lose will be directly proportional to the power output of the engine, and since the 7 radiator is well in the air stream, cooling won't be an issue.
Most 7s have bonnet louvres for aesthetic reasons and stiffening rather than cooling necessity. It will be more important to protect equipment near the exhaust with suitable heat shields if needed. Dependent on which engine is used and the underbonnet layout, sometimes alternators, starters, or batteries can get cooked. Or even the washer bottle!
I use a VW Polo Mk3 rad on my Hayabusa engined Fury. Best price I've found so far is from Northern Radiators at £21 + VAT, less than £40 delivered. The rate I'm going through them I need a cheap supplier 
At Oulton on Saturday water temp was 89 degrees at the end of a 15 minute race. I'm running a Davies Craig water pump, dry sumped with an oil cooler (oil temp 95).
At Oulton on Saturday water temp was 89 degrees at the end of a 15 minute race. I'm running a Davies Craig water pump, dry sumped with an oil cooler (oil temp 95).
thanks for the replies.
just so you know, i am running a 2003 r1 engine with a polo radiator.
the car drives fine under normal conditions and sits at around 170-180 degrees f.
however, once on track temps quickly rise to around 210-220 degrees f and beyond, and i have to therefore complete a slow lap and get it cooled down. However on my return to the pit lane and check the system, it appears the coolant has boiled and the expansion tank is dry/empty, either escaped via the overflow or somewhere else!!
due to the problems, to date i have: bled the system several times, removed the thermostat, changed the expansion tank and the cap and the problem is still present!!
any ideas?!
just so you know, i am running a 2003 r1 engine with a polo radiator.
the car drives fine under normal conditions and sits at around 170-180 degrees f.
however, once on track temps quickly rise to around 210-220 degrees f and beyond, and i have to therefore complete a slow lap and get it cooled down. However on my return to the pit lane and check the system, it appears the coolant has boiled and the expansion tank is dry/empty, either escaped via the overflow or somewhere else!!
due to the problems, to date i have: bled the system several times, removed the thermostat, changed the expansion tank and the cap and the problem is still present!!
any ideas?!
What car do you have? I can't get too technical (as I am not) but you need to have lots of venilation in the nosecone. I have heard of an MNR struggling at the 'ring as it is much more restricted than a Westfield grill/nosecone. It could be something simple as not enough flow in the nosecone or too many mashed bugs in the radiator or nosecone.
Regardless whether you are having coolant problems, you should do a cool down lap anyway.
I think the temps I typically see after a hard session is just over 90 degrees C but this drops well before it is back in the pits.
Regardless whether you are having coolant problems, you should do a cool down lap anyway.
I think the temps I typically see after a hard session is just over 90 degrees C but this drops well before it is back in the pits.
Edited by matt frost on Tuesday 8th September 11:10
I run a maestro rad, no fan, duct air up out nosecone, busa engine. As been known to "overcool" and need a few cores blocking off to bring temps up. I noticed a significant drop in both water and oil temps when I moved from the conventional set up, ducting the hot air out cools the engine bay (and transmission tunnel) a lot to.
Where is your fan, in front or behind the rad, in front can impede airflow thru the rad ?
Where is your fan, in front or behind the rad, in front can impede airflow thru the rad ?
I run a maestro rad, no fan, duct air up out nosecone, busa engine. As been known to "overcool" and need a few cores blocking off to bring temps up. I noticed a significant drop in both water and oil temps when I moved from the conventional set up, ducting the hot air out cools the engine bay (and transmission tunnel) a lot to.
Where is your fan, in front or behind the rad, in front can impede airflow thru the rad ?
Where is your fan, in front or behind the rad, in front can impede airflow thru the rad ?
Roadcaptain! said:
thanks for the replies.
just so you know, i am running a 2003 r1 engine with a polo radiator.
the car drives fine under normal conditions and sits at around 170-180 degrees f.
however, once on track temps quickly rise to around 210-220 degrees f and beyond, and i have to therefore complete a slow lap and get it cooled down. However on my return to the pit lane and check the system, it appears the coolant has boiled and the expansion tank is dry/empty, either escaped via the overflow or somewhere else
I'm running a 2003 R1 engine. It is a balanced system as the R1 engine has a combined oil and water cooling system on the bike, so you need to be careful. I left it all alone and used an R1 radiator and plumbed it up almost exactly as it is on the bike. The only concession was to add a top up / bleed tank as the system is pressured such that the header tank is below the thermostat housing. I've had no problems in my Fisher Fury R1 on road or track.just so you know, i am running a 2003 r1 engine with a polo radiator.
the car drives fine under normal conditions and sits at around 170-180 degrees f.
however, once on track temps quickly rise to around 210-220 degrees f and beyond, and i have to therefore complete a slow lap and get it cooled down. However on my return to the pit lane and check the system, it appears the coolant has boiled and the expansion tank is dry/empty, either escaped via the overflow or somewhere else
I know someone else that used a car radiator and made a right pigs ear of the cooling system. It is possible to use a car radiator (I've seen it done) but you need to plumb it all correctly to take account of the way the system is designed to work.
More than you probably want to know here:
http://www.robcollingridge.com/kitcar/design/cooli...
Rob
Just read the original post again. 210-220 degrees farenheit is 99-104 degrees C. That's not too bad and if my Fisher Fury R1 sits in traffic it will go over 110C before the fans cuts in. It's a pressurised system so it won't boil at this temp.
I've added a manual fan switch to ensure it stays below 100C though. Anyone with a bike-engined car should do this , if only to get through SVA/IVA as the car will sit there for ages whilst they check emmissions, etc. As an aside, my SVA tester told me more than half the BECs he sees over-heat before he gets to do an emmissions test!
On track, the most I've seen is 101C and that's a Fury bonnet with relatively small 'mouth' feeding an small R1 rad with no special ducting to force air through it. Typically it runs at just below 90C.
Your biggest issue is you are losing coolant! As it pressurises, the rad cap should let water past into the R1 header tank. The end of the rubber pipe from the radiator cap goes into the header tank and should always stay in liquid. As the system cools back down, it sucks water (and not air!) back through the cap. In this respect the system is air tight. If the spring in the cap has failed then too much water will escape and the system will not keep a high enough pressure. Given enough heat, water will boil at 100C when not under pressure, but you know that already :-)
Because the cooling system volume is very small (compared to a car engine), one you save weight, and two the expansion tank is relatively small and so the R1 header tank is also small.
It's a real challenge to get all the air out of the R1 engine because the thermostat housing sits on top of the engine. You have to fix this or jack up the car to remove the air in the system. I'd check you have no air, because air expands at a much higher rate for a given temperature than water. It will then push too much coolant out, overflowing the header tank. When it cools, there won't be enough liquid to suck back in and you will fill the rad with air.
I've added a manual fan switch to ensure it stays below 100C though. Anyone with a bike-engined car should do this , if only to get through SVA/IVA as the car will sit there for ages whilst they check emmissions, etc. As an aside, my SVA tester told me more than half the BECs he sees over-heat before he gets to do an emmissions test!
On track, the most I've seen is 101C and that's a Fury bonnet with relatively small 'mouth' feeding an small R1 rad with no special ducting to force air through it. Typically it runs at just below 90C.
Your biggest issue is you are losing coolant! As it pressurises, the rad cap should let water past into the R1 header tank. The end of the rubber pipe from the radiator cap goes into the header tank and should always stay in liquid. As the system cools back down, it sucks water (and not air!) back through the cap. In this respect the system is air tight. If the spring in the cap has failed then too much water will escape and the system will not keep a high enough pressure. Given enough heat, water will boil at 100C when not under pressure, but you know that already :-)
Because the cooling system volume is very small (compared to a car engine), one you save weight, and two the expansion tank is relatively small and so the R1 header tank is also small.
It's a real challenge to get all the air out of the R1 engine because the thermostat housing sits on top of the engine. You have to fix this or jack up the car to remove the air in the system. I'd check you have no air, because air expands at a much higher rate for a given temperature than water. It will then push too much coolant out, overflowing the header tank. When it cools, there won't be enough liquid to suck back in and you will fill the rad with air.
Had a similar problem with overheating on a 7 and tried to solve it by whipping the thermostat out completely. Explained it to a guy who does a lot of racing a couple of months ago and he said nooooo. Apparently the water can circulate too quickly to remove sufficient heat from the block, his recommendation, put the thermostat back in but drill a couple of holes in it and use water wetter (not sure if that compatible with a bike engine).
Sorry its took so long for an update on this post.
Anyway, after much messing around we suspected the engine was at fault, which we managed to get replaced and promptly took the car to cadwell park for a test...as you do.
The car performed faultlessly all day on track and sat at around 90d C. (max water temp)
We can only guess that there was either a defect on the head or gasket, but are just pleased its finally sorted.
Roll on next year!!
Thanks for the replies.
Anyway, after much messing around we suspected the engine was at fault, which we managed to get replaced and promptly took the car to cadwell park for a test...as you do.
The car performed faultlessly all day on track and sat at around 90d C. (max water temp)
We can only guess that there was either a defect on the head or gasket, but are just pleased its finally sorted.
Roll on next year!!
Thanks for the replies.
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