Headers causing too much engine compartment heat
Race Director
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From: Sunshine Coast, Queensland, Australia
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Cruise-In VIII Veteran
Agreed. header wrap is just horrible. as a Harley Mechanic for many years, nothing erks me more than idiots that wrap there Harley pipes with this junk. And it doesn't just look like S$!t . it rots out the pipes as well. As per heat under the hood causing all these failures. I would instead be looking at the ground cable from block to frame.
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From: Pittsburgh
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Ceramic coating the headers will help with the under the temperatures & looks better than a wrap
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All I can say is when I purchased my '74 back in '85, The previous owner put on the chrome hooker headers (which were very dented and rusty) my engine did not run hotter but the under the hood temps were very much higher than it is now with factory manifolds.
It used to vapor lock on very hot days, has not done it since the switch to manifolds. I also had to replace all the under hood wiring due to all the pastic plugs being brittle. Headers sound cool and look coool and out perform the factory manifolds, but I enjoy the lower under hood temps and cooler floor boards
It used to vapor lock on very hot days, has not done it since the switch to manifolds. I also had to replace all the under hood wiring due to all the pastic plugs being brittle. Headers sound cool and look coool and out perform the factory manifolds, but I enjoy the lower under hood temps and cooler floor boards
Last edited by walleyfisher; May 21, 2021 at 09:41 AM.
Dr. Detroit
Joined: Mar 2012
Posts: 10,091
Likes: 4,016
From: New Braunfels Texas
All I can say is when I purchased my '74 backin in '85, The previous owner put on the chrome hooker headers (which were very dented and rusty) my engine did not run hotter but the under the hood temps were very much higher than it is now with factory manifolds.
It used to vapor lock on very hot days, has not done it since the switch to manifolds. I also had to replace all the under hood wiring due to all the pastic plugs being brittle. Headers sound cool and look coool and out perform the factory manifolds, but I enjoy the lower under hood temps and cooler floor boards
It used to vapor lock on very hot days, has not done it since the switch to manifolds. I also had to replace all the under hood wiring due to all the pastic plugs being brittle. Headers sound cool and look coool and out perform the factory manifolds, but I enjoy the lower under hood temps and cooler floor boards
My friends 32’ 3-Window blown small block had chrome headers that radiated so much heat it puked the temperature sender in the head to reading 30 degrees hotter than it was.....
Ceramic coating is right up there with Mini-Starters of things that changed the Hot Rod industry....mandatory on anything I own or build.
Jebby
Had a 1976 L-82, 4-sp
Joined: Mar 2011
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From: Some days your the dog and some days your the hydrant.
Royal Canadian Navy
I have a clutch fan that's mounted vertically. I have ss headers. Heat rises. Air flow across a hot surface removes heat. A large portion of air from the fan blows across the top of the engine and under the hood. This air exits through the side vents and underneath the car. The biggest enemy to electronic/electrical devices is heat. Most electrical fans are mounted on the rad. The rad is angled. The air flow from the electrical fans points downwards with little to no flow over the top of the engine where it is needed most. Not saying heat is your problem but no air flow up top isn't helping your situation.
Safety Car
Joined: Feb 2012
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From: Orlando FL
Stan, a member of our local Corvette group (here in Orlando, FL) has a 70 with a 383. He also has an aluminum radiator with electric fans. But he also still has the mechanical fan. When I asked him about running both, he said he found that the downward angle of the electric fans was pushing air under the engine, and he found the top of his engine compartment was getting very hot. So he re-installed the mechanical fan simply to move air across the top of the engine bay & out the side vents. You may consider this, and see if it will help. Electrical parts subjected to extreme heat will fail.... ask any electrician.
Last edited by oldgto; May 21, 2021 at 06:45 PM.
Le Mans Master
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I have a clutch fan that's mounted vertically. I have ss headers. Heat rises. Air flow across a hot surface removes heat. A large portion of air from the fan blows across the top of the engine and under the hood. This air exits through the side vents and underneath the car. The biggest enemy to electronic/electrical devices is heat. Most electrical fans are mounted on the rad. The rad is angled. The air flow from the electrical fans points downwards with little to no flow over the top of the engine where it is needed most. Not saying heat is your problem but no air flow up top isn't helping your situation.
Last edited by Shovels and Vettes; May 21, 2021 at 09:17 PM.
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Had a 1976 L-82, 4-sp
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From: Some days your the dog and some days your the hydrant.
Royal Canadian Navy
Interesting.....maybe the factory equipment isn't so bad. I find many times that so called "improvement" are just another way to do something, and many times comes with just a new set of problems. My personal experience with my car just differs from what I read on this forum. First......I have almost ZERO heat in the cabin of the car........I have factory heat system installed, with factory vacuum shutoff valve......and I can drive in 90 degree weather in PA, and its is by no means HOT in the car. My right foot is six inches away from my header collector.....and I feel no heat. And I have UNCOATED stainless headers, and nothing melts under the hood, and in fact, I don't think my underhood temperature are even high. I have a good Dewitts radiator, with factory fan clutch......air flows into the engine bay, and right out the side vents and out the bottom.....NO HEAT PROBLEMS at all. I run an open 14 inch air filter.....and the engine breathes well. Lots of people with heat problems, that for some reason, my car does not. Interesting. Why is that?
But hey, some people will believe anything they read. Some of these people are just not knowledgeable enough and are easily swayed, so its not their fault. But I'm guilty too buying stuff that was over hyped. Live and learn.
