Procharged 402 stroker still running hot
Thread Starter
Safety Car
Joined: Dec 2004
Posts: 4,477
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From: Boca Raton, FL
St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14
Procharged 402 stroker still running hot
Put a new forged 402 stroker in my D1SC procharged C6. The car is still running hot in city traffic, usually in the mid to high 220's. On the open road, it runs around 208.
We've burped the cooling system, changed the 160 thermostat and put water wetter in. Still running hot.
I really don't want to change out the radiator.
Any suggestions?
BTW, with the OEM LS2 engine with the D1SC, never had this problem.
Thanks,
Jeff
We've burped the cooling system, changed the 160 thermostat and put water wetter in. Still running hot.
I really don't want to change out the radiator.
Any suggestions?
BTW, with the OEM LS2 engine with the D1SC, never had this problem.
Thanks,
Jeff
Thread Starter
Safety Car
Joined: Dec 2004
Posts: 4,477
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From: Boca Raton, FL
St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14
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Joined: Jan 2006
Posts: 4,598
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From: Miami FL
2020 C6 of the Year Finalist - Unmodified
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15-'16,'17,'18-'19-'20-'21-'22
Hey Jeff,
Things to try:
Run with NO thermostat (temporarily), to make sure the 160F thermostat you are running is not a bottleneck.
Burp the cooling system AGAIN. May still be an air pocket somewhere.
Does the tune bring in the fans EARLY, really EARLY ? Your difference between traffic conditions and open road conditions suggests not enuf air flow at lower speeds.
Did something fall in front of the radiator, or between the radiator and condensor during the engine swap? Is your air cleaner assembly stealing, or blocking, air to the radiator?
Again as a test, run with the A/C off, to see if too much rejected heat from the condensor is overloading the radiator.
What is your engine oil temperature, both in traffic and on the open road? Does it confirm that the engine is running hot?
If you are running 50-50 ethylene glycol and water, cut back to 33% ethylene glycol. Water has a much better heat transfer coefficient than ethylene glycol. If you want to run distilled water (89 cents a gallon at the grocery store) you could cut back to 25% ethylene glycol. Keep the water wetter in there in any case.
Good luck getting this under control. - Lee
Things to try:
Run with NO thermostat (temporarily), to make sure the 160F thermostat you are running is not a bottleneck.
Burp the cooling system AGAIN. May still be an air pocket somewhere.
Does the tune bring in the fans EARLY, really EARLY ? Your difference between traffic conditions and open road conditions suggests not enuf air flow at lower speeds.
Did something fall in front of the radiator, or between the radiator and condensor during the engine swap? Is your air cleaner assembly stealing, or blocking, air to the radiator?
Again as a test, run with the A/C off, to see if too much rejected heat from the condensor is overloading the radiator.
What is your engine oil temperature, both in traffic and on the open road? Does it confirm that the engine is running hot?
If you are running 50-50 ethylene glycol and water, cut back to 33% ethylene glycol. Water has a much better heat transfer coefficient than ethylene glycol. If you want to run distilled water (89 cents a gallon at the grocery store) you could cut back to 25% ethylene glycol. Keep the water wetter in there in any case.
Good luck getting this under control. - Lee
Thread Starter
Safety Car
Joined: Dec 2004
Posts: 4,477
Likes: 2
From: Boca Raton, FL
St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14
What is your engine oil temperature, both in traffic and on the open road? Does it confirm that the engine is running hot?
Lee
I think the oil temp is in the 230's, I'll check next time I'm in the vette.
Thanks for the other suggestions, I'll pass them on to Roger and Jeremy.
Jeff
Lee
I think the oil temp is in the 230's, I'll check next time I'm in the vette.
Thanks for the other suggestions, I'll pass them on to Roger and Jeremy.
Jeff
Former Vendor
Joined: Aug 2005
Posts: 16,897
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From: Lewisville TX
St. Jude Donor '03-'04-'05-'06-'07-'08-'09-'10-'11-'12-'13
It's probably going to need a larger radiator.
Not only is the intercooler blocking some of the air flow coming into the radiator, you are also building a lot more power than before which also increases the amount of heat being produced by the engine. The blower itself gets hot, and that air is trapped under the hood of the car, further increasing heat soak.
The only real way to help this is by increasing the thermal cap. of the cooling system with a larger radiator, after you have done all of the other items like the 160 stat, coolant...so on and so forth.
Not only is the intercooler blocking some of the air flow coming into the radiator, you are also building a lot more power than before which also increases the amount of heat being produced by the engine. The blower itself gets hot, and that air is trapped under the hood of the car, further increasing heat soak.
The only real way to help this is by increasing the thermal cap. of the cooling system with a larger radiator, after you have done all of the other items like the 160 stat, coolant...so on and so forth.
Tech Contributor
Joined: Jul 2002
Posts: 14,950
Likes: 264
From: St. Louis, MO
St. Jude Donor '08
Jeff, Doug had this problem too when he put in his 402 (GTOdoug), if I recall he let his car run with the radiator cap off for a long time, letting it burp coolant out until it got all the air bubbles out, and then made sure the system was full and capped it off. That did it if I recall --- you might want to PM him before you spend any more money.
Last edited by Joe_G; Jul 5, 2008 at 02:49 PM.
Instructor
Joined: Apr 2005
Posts: 168
Likes: 0
From: Austin TX
space between the intercooler and radiator can cause a low pressure area, and actually cause poor airflow through the radiator. do you at least have some sort of ducting that forces the air through the radiator after it passes through the radiator?
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Put a new forged 402 stroker in my D1SC procharged C6. The car is still running hot in city traffic, usually in the mid to high 220's. On the open road, it runs around 208.
We've burped the cooling system, changed the 160 thermostat and put water wetter in. Still running hot.
I really don't want to change out the radiator.
Any suggestions?
BTW, with the OEM LS2 engine with the D1SC, never had this problem.
Thanks,
Jeff
We've burped the cooling system, changed the 160 thermostat and put water wetter in. Still running hot.
I really don't want to change out the radiator.
Any suggestions?
BTW, with the OEM LS2 engine with the D1SC, never had this problem.
Thanks,
Jeff
Thread Starter
Safety Car
Joined: Dec 2004
Posts: 4,477
Likes: 2
From: Boca Raton, FL
St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14
Joe
How ya been, long time no see. Thought you might drive up to HPS drag day. I stopped in just to say "Hi".
Did Dougie's suggestion when the problem started. Jeremy was familiar with it and tried to "burp" the coolant several times. I put 2 bottles of wetter water in after that. No change.
The issue in not when I'm running on the open road, it's in city traffic. Temp almost went into the red a couple of weeks ago, had me really concerned.
Jeff
How ya been, long time no see. Thought you might drive up to HPS drag day. I stopped in just to say "Hi".
Did Dougie's suggestion when the problem started. Jeremy was familiar with it and tried to "burp" the coolant several times. I put 2 bottles of wetter water in after that. No change.
The issue in not when I'm running on the open road, it's in city traffic. Temp almost went into the red a couple of weeks ago, had me really concerned.
Jeff
Jeff, Doug had this problem too when he put in his 402 (GTOdoug), if I recall he let his car run with the radiator cap off for a long time, letting it burp coolant out until it got all the air bubbles out, and then made sure the system was full and capped it off. That did it if I recall --- you might want to PM him before you spend any more money.
Racer
Joined: Dec 2007
Posts: 413
Likes: 0
From: Bradenton Fl
When i had my forged/cammed 402 thrown in then adding a D1, i also ran hot. Had the 160 tstat and fans to come on early. It took a week or two of riding around(basically the 500 mile new motor break in) to where it eventually stays around 194, 215 with air on full blast. if i get stuck at a light, the temps will climb to 230.
Then i did the big bollas mod, and honestly imo it was a waste of time, temps maybe dropped 3* at most in city traffic.
Just hope your alternator doesnt start heat soaking, seeing "service charging system" every 3 seconds makes driving horrible.
Edit.. forgot to mention.
While messing around with the supercharger(ate a couple belts), my builder noticed some debris between my radiator and ac condenser. So i took a air hose and a scrubber and went to town on those fins. After about 15mins of scrubbing and using the air, i had a miniature iraq sitting under my car, think one of my neighbors cats was in there as well.
For a while after that, my temps never went above 186-190 in the city, stop an go...so make sure you clean between those two pieces often.
Then i did the big bollas mod, and honestly imo it was a waste of time, temps maybe dropped 3* at most in city traffic.
Just hope your alternator doesnt start heat soaking, seeing "service charging system" every 3 seconds makes driving horrible.
Edit.. forgot to mention.
While messing around with the supercharger(ate a couple belts), my builder noticed some debris between my radiator and ac condenser. So i took a air hose and a scrubber and went to town on those fins. After about 15mins of scrubbing and using the air, i had a miniature iraq sitting under my car, think one of my neighbors cats was in there as well.
For a while after that, my temps never went above 186-190 in the city, stop an go...so make sure you clean between those two pieces often.
Last edited by LS2POWA; Jul 5, 2008 at 11:27 PM.
Thread Starter
Safety Car
Joined: Dec 2004
Posts: 4,477
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From: Boca Raton, FL
St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14
Thread Starter
Safety Car
Joined: Dec 2004
Posts: 4,477
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From: Boca Raton, FL
St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14
Corey,
Our temps are about the same, maybe it just the way it's going to be and I should not worry about it.
Thanks,
Jeff
Our temps are about the same, maybe it just the way it's going to be and I should not worry about it.
Thanks,
Jeff
When i had my forged/cammed 402 thrown in then adding a D1, i also ran hot. Had the 160 tstat and fans to come on early. It took a week or two of riding around(basically the 500 mile new motor break in) to where it eventually stays around 194, 215 with air on full blast. if i get stuck at a light, the temps will climb to 230.
Then i did the big bollas mod, and honestly imo it was a waste of time, temps maybe dropped 3* at most in city traffic.
Just hope your alternator doesnt start heat soaking, seeing "service charging system" every 3 seconds makes driving horrible.
Then i did the big bollas mod, and honestly imo it was a waste of time, temps maybe dropped 3* at most in city traffic.
Just hope your alternator doesnt start heat soaking, seeing "service charging system" every 3 seconds makes driving horrible.
Advanced
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Racer
Joined: Dec 2007
Posts: 413
Likes: 0
From: Bradenton Fl
I was told to invest in a bigger radiator, but my temps are still lower then stock with all the work done.
I just get upset when i constantly see the dic read service charging system. I know the local chevy dealer fixed it once, but not sure if they can solve it again. which sucks cause i have a whole system waiting to go in.
I just get upset when i constantly see the dic read service charging system. I know the local chevy dealer fixed it once, but not sure if they can solve it again. which sucks cause i have a whole system waiting to go in.
