First some background, I’m the original owner of this 37,000 mile cobra, I’m a retired Ford tech. Last fall at a open track weekend on the last session the car started to get hot and went into a reduced power mode, I immediately pulled off and let the car cool and drove it home, there was no coolant loss. So forward to this month I upgraded the cooling system with a new Fluidine radiator, new hoses, water pump, belts, and idler bearings. I properly filled the system and drove the car over 150 miles, some of it in 100 degree heat with the a/c on and the engine temperature never went over 225 degrees. This weekend I had a track event at Willow Springs with air temp of 90-95 degrees and after 4 hard laps the engine temp went to 240 and started blowing coolant out of the cap. I let the engine cool added more coolant and water wetter, went out again and in 4 laps same results, 240 coolant blowing out. I did that 3 more times, same result. I then drove home for over 100 miles with a/c on driving normal speeds and coolant temp 190-220 in 85 degrees with no over heating. After I let the engine cool I checked and added 2 quarts, no leaks that I can see at this time. With all that said I think the engine is burning it and when in a boost condition it causes a overheating. I am thinking of doing a cylinder leakdown test to see what I can find out. I think it could be a head gasket or cracked head or could it be as simple as a intake gasket. What do you guys think is the most likely? Thanks I know its along post.
Cooling System Issues
- Thread starter CSCOBRA03
- Start date
It’s a Rieshe 172 and new this month.
Well sounds like you maybe on to something with being under boost causing an issue
My guess is headgasket also. Had a similar situation. Drove the car after getting it back together and put on about 400 miles. Couple 1 hour trips and then another 2.5 hour trip. Stopped for food and after taking back off onto the highway (car was up to temp) and got on it a bit within a half miles temp gauge pegged and the car was falling on its face. Limped it to our hotel and it was blowing out the over flow cap. Next morning pulled all the plugs and turned it over and had a geyser shooting out of the number 3 cylinder. If it's not the headgasket it may be a cracked cylinder. Definitely time for a compression test.
Good luck!
Ken
Good luck!
Ken
Hey there. First off great to see you tracking your cobra. Much love to ya there. I got my cobra last year from the original owner my uncle. I'll give you some advice and some insight onto the build of my car. My car is a 12k mile cobra with about 9k miles of open track abuse. Very little street miles... first 1k was on the street so in 11k miles only about 2k are on the road.
My cobra has been extensively modded for the track. It's a trailer queen dedicated road race car. Years and years of trial and error that my uncle endured to get the car to where it is now. The car has ran in 90f heat for 40 minute sessions at gingerman and mid ohio. My first event last year in houston was 94f heat and I did 20 minute sessions and never skipped a beat. Now this is of course depending on the driver... I'm a novice but my uncle was an instructor. He drove it hard and dealt with heat issues until he came up with the combo that is on the car now that allowed him to run 40 minute sessions without issues.
Here is my car cooling setup:
2.3 gen2 whipple (cooler discharge vs eaton) 14psi 570rwhp/520rwtq
afco h/e
fluidyne radiator
lethal gen2 head cooling mod
bypass hose delete
thermostat delete
AC delete
Evans coolant
So this is where he modded the car to. The car can/will go into limp mode above 240f coolant temps. I think mine has been tuned to 235. Same thing for iat2... I think stock it's rated 200f it'll go into limp mode.
So your a tech so obviously do the compression and leakdown. It could very well be a head gasket issue. However, my uncle had the same experience you had where he couldn't do more than 2-3 hard laps before he would have to back way off. The evans coolant he said was a big contributor along with the head cooling mod. The lethal design brings the hot cyl 7/8 coolant out of the head and brings it directly back to the radiator via a splice in the upper tube. There is no more recirculating/mixing hot coolant with cool due to the bypass delete and the thermostat delete was the final thing he did. I'm not sure if he has a restrictor plate in the hose or not but I don't think he does.
My other uncle is a ford tech and they both tore the motor down around 8-9k miles to the shortblock to inspect the cylinders and to install the head studs and new timing assembly. New water and oil pumps too. Everything looked very clean and they deemed the motor acceptable.
The cobra had 11,646 miles when I bought it and immediately did new plugs/coils and I did a compression test then and got 180 on 6 cylinders and one had 175 and one had 185. I believe this falls within the ford spec.
Let me know if there is any questions. Hope you get it corrected because tracking the cobra is simply amazing!
My cobra has been extensively modded for the track. It's a trailer queen dedicated road race car. Years and years of trial and error that my uncle endured to get the car to where it is now. The car has ran in 90f heat for 40 minute sessions at gingerman and mid ohio. My first event last year in houston was 94f heat and I did 20 minute sessions and never skipped a beat. Now this is of course depending on the driver... I'm a novice but my uncle was an instructor. He drove it hard and dealt with heat issues until he came up with the combo that is on the car now that allowed him to run 40 minute sessions without issues.
Here is my car cooling setup:
2.3 gen2 whipple (cooler discharge vs eaton) 14psi 570rwhp/520rwtq
afco h/e
fluidyne radiator
lethal gen2 head cooling mod
bypass hose delete
thermostat delete
AC delete
Evans coolant
So this is where he modded the car to. The car can/will go into limp mode above 240f coolant temps. I think mine has been tuned to 235. Same thing for iat2... I think stock it's rated 200f it'll go into limp mode.
So your a tech so obviously do the compression and leakdown. It could very well be a head gasket issue. However, my uncle had the same experience you had where he couldn't do more than 2-3 hard laps before he would have to back way off. The evans coolant he said was a big contributor along with the head cooling mod. The lethal design brings the hot cyl 7/8 coolant out of the head and brings it directly back to the radiator via a splice in the upper tube. There is no more recirculating/mixing hot coolant with cool due to the bypass delete and the thermostat delete was the final thing he did. I'm not sure if he has a restrictor plate in the hose or not but I don't think he does.
My other uncle is a ford tech and they both tore the motor down around 8-9k miles to the shortblock to inspect the cylinders and to install the head studs and new timing assembly. New water and oil pumps too. Everything looked very clean and they deemed the motor acceptable.
The cobra had 11,646 miles when I bought it and immediately did new plugs/coils and I did a compression test then and got 180 on 6 cylinders and one had 175 and one had 185. I believe this falls within the ford spec.
Let me know if there is any questions. Hope you get it corrected because tracking the cobra is simply amazing!
You might need to look into getting the hot air out of the engine bay. Things like fencing the radiator in and going with a race type hood.
Provided the engine is in good health.
Provided the engine is in good health.
IAT2 pulls timing around 150 degrees
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Sent from my iPad using Tapatalk
This is all good info for sure, I did most everything you did less the cylinder head cooling mod. I think this overheating issue may be resolved now, by vacuum filling the cooling system and changing the cooling fan temp settings. My tuner was a big help so we did some tune changes as well, it's hard to test the results without being on the track. I have done back to back to back hard pulls in high heat with good results, no coolant loss or blow out, temps of max 220 degrees. I have one question, what is the temp of your cobras just driving in high heat with the A/c on ? Mine is about 190 but will go up to 220 when using it hard.
I’m stock.
When I had these issues
Radiator was my cause.
New radiator/170stat
I now see 178-182 with over 100 outside
Temps climb when stopped but you see temps fall as soon as you move
I’ve had drivers side head issues
Both 4/9 thread
On updated drivers now.
Passenger is original 4 thread
When I had these issues
Radiator was my cause.
New radiator/170stat
I now see 178-182 with over 100 outside
Temps climb when stopped but you see temps fall as soon as you move
I’ve had drivers side head issues
Both 4/9 thread
On updated drivers now.
Passenger is original 4 thread
I had a similar problem with overheating/engine cooling - might check to see if you have an intermittent intercooler pump. The coolant in the intercooler tank should be constantly turbulent... mine stopped flowing occasionally and that's all it took. What's odd here is that my Cobra is also a one owner with approx. 38,000 on the clock. Things that make you say hummmmmm.
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My car doesn't have AC. However, my normal driving around temps are 178-184. I've only seen it rise to 212-214 during road racing but nothing hotter and that was in 94F heat.
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