Stock cooling system design question
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Joined: May 2009
Posts: 227
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From: Long Island, NY
Engine: LB9 5.0L TPI
Transmission: T-5
Axle/Gears: 9-bolt Borg Warner, 3.45
Stock cooling system design question
My 89 305 TPI formula is bone stock and has the factory dual fan radiator set up. The fans kick on as they should at the specified temps. I've checked with my temp gun.
My question is, if I leave my car idling, it always heats up to 235 and my fan kicks on and keeps it there. If my fans were to fail though the car would overheat. Is that how GM designed these cars and does that happen to other people's birds?
My question is, if I leave my car idling, it always heats up to 235 and my fan kicks on and keeps it there. If my fans were to fail though the car would overheat. Is that how GM designed these cars and does that happen to other people's birds?
Joined: May 2013
Posts: 1,493
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From: CT
Car: 86 Trans Am WS6
Engine: 383 stroker
Transmission: 700r4
Axle/Gears: 9 Bolt Torsen 3.70
Re: Stock cooling system design question
I think that theory pretty much goes with any car, the fans keep the engine cool when its not moving but when it is moving it relies on the flow of air to cool the engine. How often do you leave your car just idling?
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Member

Joined: May 2009
Posts: 227
Likes: 2
From: Long Island, NY
Engine: LB9 5.0L TPI
Transmission: T-5
Axle/Gears: 9-bolt Borg Warner, 3.45
Re: Stock cooling system design question
I guess that's true. I think on modern cars the fan is always running so u don't see the temp fluctuate as much. Would u agree? I only let it idle in the winter when I start it every week.
Re: Stock cooling system design question
My 89 305 TPI formula is bone stock and has the factory dual fan radiator set up. The fans kick on as they should at the specified temps. I've checked with my temp gun.
My question is, if I leave my car idling, it always heats up to 235 and my fan kicks on and keeps it there. If my fans were to fail though the car would overheat. Is that how GM designed these cars and does that happen to other people's birds?
My question is, if I leave my car idling, it always heats up to 235 and my fan kicks on and keeps it there. If my fans were to fail though the car would overheat. Is that how GM designed these cars and does that happen to other people's birds?
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Joined: Apr 2014
Posts: 100
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From: Eastern PA
Car: 1988 GTA
Engine: VIN F 305 TPI
Transmission: AUto
Re: Stock cooling system design question
When you leave a cold engine idle, it has to run rich. This can wash the lubrication off your rings because all the fuel is not burnt. It also is hard on the cats (if you have them). I know it is cold inside, but it is much better for your car to start it, let it warm a minute or two and then drive away. This will bring it to temperature quickly. A cold engine is about as bad as it get on a car. Fuel injection does not cure this because a cold engine has to run rich and the computer knows this. It substitutes extra pulses of the injectors for a choke.
Joined: Jul 2011
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From: Davison, MI
Car: 89 Camaro
Engine: Dart SHP 400-Holley Terminator EFI
Transmission: Tremec T56 Magnum F
Axle/Gears: Strange S60 3.55:1
Re: Stock cooling system design question
When you leave a cold engine idle, it has to run rich. This can wash the lubrication off your rings because all the fuel is not burnt. It also is hard on the cats (if you have them). I know it is cold inside, but it is much better for your car to start it, let it warm a minute or two and then drive away. This will bring it to temperature quickly. A cold engine is about as bad as it get on a car. Fuel injection does not cure this because a cold engine has to run rich and the computer knows this. It substitutes extra pulses of the injectors for a choke.
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Joined: May 2009
Posts: 227
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From: Long Island, NY
Engine: LB9 5.0L TPI
Transmission: T-5
Axle/Gears: 9-bolt Borg Warner, 3.45
Re: Stock cooling system design question
Haha, in fairness my bird always smells like it's running rich when i let it idle for a bit
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Joined: Apr 2014
Posts: 100
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From: Eastern PA
Car: 1988 GTA
Engine: VIN F 305 TPI
Transmission: AUto
Re: Stock cooling system design question
Let see, 55 years on cars starting with a 1931 Model A back in 1961. Owning and servicing over 20 vehicles from VW, Jaguar V12's, Rovers, Fords, Pontiac's, Mercedes gas and diesels and 3 million driven miles. Masters in Mechanical Engineering, Designed fans for Ford, Cadillac and Chrysler, along with missile nosecone ultrasonic testing equipment, multiple patents in semiconductor equipment and don't even look at Facebook. I would never post "stupid stuff". You have the right to ignore anything that is posted on this or any BB.
What is a college intern?
What is a college intern?
Joined: Jul 2011
Posts: 744
Likes: 5
From: Davison, MI
Car: 89 Camaro
Engine: Dart SHP 400-Holley Terminator EFI
Transmission: Tremec T56 Magnum F
Axle/Gears: Strange S60 3.55:1
Re: Stock cooling system design question
Let see, 55 years on cars starting with a 1931 Model A back in 1961. Owning and servicing over 20 vehicles from VW, Jaguar V12's, Rovers, Fords, Pontiac's, Mercedes gas and diesels and 3 million driven miles. Masters in Mechanical Engineering, Designed fans for Ford, Cadillac and Chrysler, along with missile nosecone ultrasonic testing equipment, multiple patents in semiconductor equipment and don't even look at Facebook. I would never post "stupid stuff". You have the right to ignore anything that is posted on this or any BB.
What is a college intern?
What is a college intern?
I drive 40,000 miles a year, and have done so for the last 16 years, owning only 4 used, high-mileage vehicles in that period of time. Each idling for 10-20 minutes to warm up on the cold days and only changing the oil when the oil life monitor said it was time, which was usually between 6,000 to 6,700 miles. Do you know how many engines I had to put new rings in? Zero.
bop11 - I apologize if you were not referring to that article; but the article I mention sounds nearly identical to your post and that article isn't correct. Whether you read the article or not isn't as important as what you are saying isn't completely true. I would agree that if your engine was malfunctioning and running so pig rich that it had poor drivability, then your scenario would be more plausible, but in a properly running engine, letting it idle to warm up will not cause enough wear to ever experience engine failure for that reason. Something else will break in that engine, or it will just wear out from normal use LONG before ring failure for letting it idle cold will ever be the root cause failure mode. How many engines out of those 20 vehicles ever failed because of worn rings, that were worn prematurely by reason of cold idling? I'll guess zero.
To the OP, I apologize for taking your thread off topic.
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Joined: Jul 2007
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From: Howard Lake, MN
Car: 86 Camaro
Engine: 355- hopefully a 5.3 this summer
Transmission: 700r4
Axle/Gears: 3.42
Re: Stock cooling system design question
yes, it's normal for the fans to kick on at what seems like a high temp and keep it there... they did it that way for emissions. yes, electrical fans can go bad and cause overheating, but so can a clutch on a mechanical fan.
also, it's better to start an engine, let it warm up for maybe 30 seconds tops, and then drive it... not only does it warm it up faster when it's loaded but you aren't burning up gas just sitting there..
also, it's better to start an engine, let it warm up for maybe 30 seconds tops, and then drive it... not only does it warm it up faster when it's loaded but you aren't burning up gas just sitting there..
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Member

Joined: May 2009
Posts: 227
Likes: 2
From: Long Island, NY
Engine: LB9 5.0L TPI
Transmission: T-5
Axle/Gears: 9-bolt Borg Warner, 3.45
Re: Stock cooling system design question
yes, it's normal for the fans to kick on at what seems like a high temp and keep it there... they did it that way for emissions. yes, electrical fans can go bad and cause overheating, but so can a clutch on a mechanical fan.
also, it's better to start an engine, let it warm up for maybe 30 seconds tops, and then drive it... not only does it warm it up faster when it's loaded but you aren't burning up gas just sitting there..
also, it's better to start an engine, let it warm up for maybe 30 seconds tops, and then drive it... not only does it warm it up faster when it's loaded but you aren't burning up gas just sitting there..
Joined: Oct 2001
Posts: 12,212
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From: Il
Car: 1989-92 FORMULA350 305 92 Hawkclone
Engine: 4++,350 & 305 CIs
Transmission: 700R4 4800 vig 18th700R4 t56 ZF6 T5
Axle/Gears: 3.70 9"ford alum chunk,dana44,9bolt
Re: Stock cooling system design question
The 2nd fan kicks on at 239* or when the AC is switched on. Yes as said above, its for emssions reasons.
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