Headers are glowing???
Thread Starter
Melting Slicks
Joined: Feb 2002
Posts: 2,699
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From: The Black Hole LA
Headers are glowing???
91, 383 with long tube ceramic coated headers.
Just took the my car out of hibernation since it has started to warm up here a bit and noticed that the headers were glowing slightly. This was at night so when I openned the hood it was dark obviously and I could see 7 of the eight glowing slightly. This is after it had been idling for only 5 minutes or so. The engine was not even up to temp yet. Is this normal on this type of set up? I've never noticed it before, but I don't think I've ever openned the hood up in the dark either (I had a flashlight I just wanted to look around to make sure everything was working properly).
Just took the my car out of hibernation since it has started to warm up here a bit and noticed that the headers were glowing slightly. This was at night so when I openned the hood it was dark obviously and I could see 7 of the eight glowing slightly. This is after it had been idling for only 5 minutes or so. The engine was not even up to temp yet. Is this normal on this type of set up? I've never noticed it before, but I don't think I've ever openned the hood up in the dark either (I had a flashlight I just wanted to look around to make sure everything was working properly).
Melting Slicks
Joined: Mar 2002
Posts: 3,108
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From: S.L.C. UT
Actually, I have seen engines that are way rich do that, caused by fuel in the headers give a afterburn effect. Lean will make your engine run hotter, but the glowing exhaust is from the afterburn effect.
When I was dealing with chips on one of my 421's, I saw my car do that when it was dark, and it was pig rich.
When I was dealing with chips on one of my 421's, I saw my car do that when it was dark, and it was pig rich.
Thread Starter
Melting Slicks
Joined: Feb 2002
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From: The Black Hole LA
PCMforless did the tune. I've always thought it was a little rich because of the slight smell of fuel when it wasn't warmed up. I never had it dyno tuned because there is no one that does that around here. 5 hours away is the closest place.
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From: moraga ca
Actually, I have seen engines that are way rich do that, caused by fuel in the headers give a afterburn effect. Lean will make your engine run hotter, but the glowing exhaust is from the afterburn effect.
When I was dealing with chips on one of my 421's, I saw my car do that when it was dark, and it was pig rich.
When I was dealing with chips on one of my 421's, I saw my car do that when it was dark, and it was pig rich.
When I run my 406 at a fast idle (2500rpm) for 30 seconds or so, my headers will start to turn red and after a minute will turn bright red. Probably a combination of late timing and too much fuel at that fuel cell. I don't do it often so I haven't spent any time worrying about it or tuning it out. It doesn't hurt anything but it can melt things close to the headers. Willie
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From: Overland Park Kansas
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Besides being rich, I've also seen reports of glowing headers that was due to the timing being retarded. By not sending the spark soon enough, the fuel is still burning as the exhaust valves open up. This could be caused by having the dizzy off it's mark or a mistake in the bin.
Interesting that one of the eight isn't glowing though....
How is it running? Power? Have you run a scan to show anyone -- in lieu of a dyno run?
Interesting that one of the eight isn't glowing though....
How is it running? Power? Have you run a scan to show anyone -- in lieu of a dyno run?
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Melting Slicks
Joined: Nov 2008
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If You have JET HOT COATED CERAMIC STYLE HEADERS,
Dont let them glow Cherry Red too Long.
You will discolor or even worse blister the coating.
It can be polished out but only to a certain degree.
Running an engine at high idle above 2,000 rpm's in a driveway will turn most any exaughst system cherry red and even the catalytic converters if intact in just a few minutes.
There is no usual road driving speeds of airflow over any of the exaughst system.
So it overheats just as if the ignition timing is way retarded from where it has to be.
Or as if the engine is running extremely lean on fuel delivery.
BR
Dont let them glow Cherry Red too Long.
You will discolor or even worse blister the coating.
It can be polished out but only to a certain degree.
Running an engine at high idle above 2,000 rpm's in a driveway will turn most any exaughst system cherry red and even the catalytic converters if intact in just a few minutes.
There is no usual road driving speeds of airflow over any of the exaughst system.
So it overheats just as if the ignition timing is way retarded from where it has to be.
Or as if the engine is running extremely lean on fuel delivery.
BR
Melting Slicks
Joined: Nov 2008
Posts: 2,765
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Engines on a water brake dyno like a Superflow with the engine pulling hard
to get dyno numbers from 2,000 to 7,000 RPM's plus will also make
exahust headers glow bright Cherry Red.
Especially if the shop lights are turned off.
Had a Pontiac 455 dynoed years ago.
The Hooker Super Competition exahust headers glowed like they were going to melt off.
After 15 back to back dyno pulls.
BSFC numbers were right on too along with ignition timing lead.
The headers never melted off. Was concerned at the time though.
BR
to get dyno numbers from 2,000 to 7,000 RPM's plus will also make
exahust headers glow bright Cherry Red.
Especially if the shop lights are turned off.
Had a Pontiac 455 dynoed years ago.
The Hooker Super Competition exahust headers glowed like they were going to melt off.
After 15 back to back dyno pulls.
BSFC numbers were right on too along with ignition timing lead.
The headers never melted off. Was concerned at the time though.
BR
Last edited by 87 vette 81 big girl; Feb 15, 2011 at 11:29 PM.
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Isn't it a bit early to diagnose a bad tune?
Cars been parked for the winter and was only idling for 5 minutes.
Didn't get up to running temp so most likely its still in open loop.
I'd take it for an easy ride and wait until operating temp is reached.
Cars been parked for the winter and was only idling for 5 minutes.
Didn't get up to running temp so most likely its still in open loop.
I'd take it for an easy ride and wait until operating temp is reached.
Last edited by JrRifleCoach; Feb 15, 2011 at 11:36 PM.
Team Owner
Joined: Aug 2004
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From: Park City Utah
All of the above CAN cause glowing headers at idle. Too rich, too lean, overly retarded timing...and one other thing; a restriction in the exhaust will do it too. It's been sitting a while?
Also, you are in NO danger of "burning valves and other parts of the engine" when idling, regardless of how lean it is. Just not enough energy in that thin mix and not enough heat at that slow cycle speed.
Also, you are in NO danger of "burning valves and other parts of the engine" when idling, regardless of how lean it is. Just not enough energy in that thin mix and not enough heat at that slow cycle speed.
Thread Starter
Melting Slicks
Joined: Feb 2002
Posts: 2,699
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From: The Black Hole LA
I'm going to borrow a timing light to check and re-set the timing. I'm thinking that is the optimal place to start, especially since as my other thread states I was also having idling issues. I did adjust the distributor a little to see if it would help the idle. I put it back where it was but I could be just slightly off.
After that I think I will finally get the tune dialed in. It was close from PCMforless, but I've always thought it wasn't quite perfect. I've got the cord to hook to a laptop, but that laptop I used is long gone so I'll have to download a program to read it again. Any suggestions.
After that I think I will finally get the tune dialed in. It was close from PCMforless, but I've always thought it wasn't quite perfect. I've got the cord to hook to a laptop, but that laptop I used is long gone so I'll have to download a program to read it again. Any suggestions.
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From: Hartford WI
I had that once and what it was will shock you. Injector fuse blew and one bank was lean. Left bank. So the ECM dumped fuel into all of it which made the right bank super rich and glowed the headers
