Glowing header tubes
Thread Starter
Le Mans Master
Joined: May 2004
Posts: 5,866
Likes: 60
From: Hellinois
Finalist 2020 C4 of the Year - Modified
Glowing header tubes
Finally got the car to start and run correct but now I have another concern, (as usual). #3-5-7 header tubes start to glow if I hold the rpm's around 1,500 but they cool back down when I let off it. Any ideas as to what may be wrong? These 3 tubes are the only ones doing this with #7 being the worst. I know I've seen this covered before but a search came up empty.
Burning Brakes
Joined: Nov 2003
Posts: 914
Likes: 1
From: Redding Ca
You're running very lean. Have you removed the distributor lately? Your timing is way off.
Very odd only one bank. I have only seen glowing headers where timing was way off, either the distributor setting or the timing chain one tooth off. Since only one bank is glowing could it be those cylinders are not getting sufficient fuel so are extremely lean? I do not know what would cause only 1/2 the engine to be lean.
Very odd only one bank. I have only seen glowing headers where timing was way off, either the distributor setting or the timing chain one tooth off. Since only one bank is glowing could it be those cylinders are not getting sufficient fuel so are extremely lean? I do not know what would cause only 1/2 the engine to be lean.
Burning Brakes
Joined: Nov 2005
Posts: 848
Likes: 1
From: 1992 LT1 6 speed Cayman Islands
Injectors
Injectors on those cylinders dirty causing a lean condition at elevated RPM when they cant keep up even though they flow enough at idle.
Try abottle of injector cleaner in the gas tank and see if it clears up over time
Try abottle of injector cleaner in the gas tank and see if it clears up over time
Thread Starter
Le Mans Master
Joined: May 2004
Posts: 5,866
Likes: 60
From: Hellinois
Finalist 2020 C4 of the Year - Modified
All brand new injectors. I went back out after dark so I could see the glow better, I was mistaken both banks are glowing. As I said the timing is right on 6 degrees advance. Any more ideas?
Advanced
Joined: Feb 2005
Posts: 77
Likes: 1
From: zanesville ohio
do you have an adjustable fuel pressure regulator? if you do i would set your pressure at 47 psi, the reason there getting hot and glowing is because your running lean, anytime you put long tubes on a fuel injected motor you have to kick the fuel pressure up a couple notches. this will also make your car perform at it's best with the headers. 
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Burning Brakes
Joined: Sep 2003
Posts: 875
Likes: 0
From: Louisville KY
if its any help, I used a computer controlled distributor bottom on a carbed car on accident (in other words there would be no advance other than initial). Let me tell you, have you ever seen header tubes glow bright pink? yeah, all of that unburned fuel was burning off in the header tubes... baked my ceramic coating as well.
Le Mans Master
Joined: Feb 2000
Posts: 9,715
Likes: 27
From: Kempner Texas
The most common cause, as others have said, is ignition timing. Retarded ignition timing advance is usually the culprit.
Did you disconnect the EST before setting the initial timing? If so, did you remember to plug it back in and clear the stored code?
I had this happen once when the ECM failed and would not take over the ignition timing chores after start up; I had beautiful orange colored headers.
Swapping in a friend's ECM returned things to normal, so I bought a replacement ECM from O'Reilly's for about $100. That was about four years ago and haven't had that problem since.
So I recommend first checking to see if the advance is increasing to the range of 20/24 degrees BTDC while the engine is idling.
If it is, then try this: reset the initial timing to 10 degress BTDC, clear the code that gets stored the refire the engine and let it idle. See if that causes the glowing to stop.
If all that checks out and the headers are still glowing, you can try increasing fuel pressure, larger injectors and/or PROM re-burn.
Jake
Did you disconnect the EST before setting the initial timing? If so, did you remember to plug it back in and clear the stored code?
I had this happen once when the ECM failed and would not take over the ignition timing chores after start up; I had beautiful orange colored headers.
Swapping in a friend's ECM returned things to normal, so I bought a replacement ECM from O'Reilly's for about $100. That was about four years ago and haven't had that problem since.
So I recommend first checking to see if the advance is increasing to the range of 20/24 degrees BTDC while the engine is idling.
If it is, then try this: reset the initial timing to 10 degress BTDC, clear the code that gets stored the refire the engine and let it idle. See if that causes the glowing to stop.
If all that checks out and the headers are still glowing, you can try increasing fuel pressure, larger injectors and/or PROM re-burn.
Jake
Last edited by JAKE; Jan 11, 2006 at 09:27 PM. Reason: Additional Comments
Thread Starter
Le Mans Master
Joined: May 2004
Posts: 5,866
Likes: 60
From: Hellinois
Finalist 2020 C4 of the Year - Modified
Thanks to all who answered, the valves are set right, I double checked those. About the only thing I haven't tried is bringing up the fuel pressure, it's 42 now so tomorrow I'll raise it to 47 and cross my fingers. I'll post results. Timing is set at 6 degrees as I said and advances to about 18-20, (in that area) when I reconnect EST. I don't have a timing light to measure advance so this figure is just a guess. I put in pink top injectors from FiveO Motorsports and I seem to remember they need more pressure than the Bosch so I hope that's it.
Race Director
Joined: Aug 2000
Posts: 11,506
Likes: 4
From: Vancouver,Wa.
One thing that happen to me in the past was the ballancer spun on its hub.. So there was really no way to tell what the timing was set at.
Last edited by Corvette0096; Jan 11, 2006 at 11:25 PM.
Le Mans Master
Joined: Feb 2000
Posts: 9,715
Likes: 27
From: Kempner Texas
Originally Posted by Midnight 85
Thanks to all who answered, the valves are set right, I double checked those. About the only thing I haven't tried is bringing up the fuel pressure, it's 42 now so tomorrow I'll raise it to 47 and cross my fingers. I'll post results. Timing is set at 6 degrees as I said and advances to about 18-20, (in that area) when I reconnect EST. I don't have a timing light to measure advance so this figure is just a guess. I put in pink top injectors from FiveO Motorsports and I seem to remember they need more pressure than the Bosch so I hope that's it.
Guys who run Ford injectors can give you more specific details, but from what I've read, a lot depends on the fuel pressure the injector is rated at.
All injectors aren't rated at the same pressure. The ones that come in our cars stock from the factory are rated at 43.5 psi. I believe the Ford injectors are rated at a different value, so it would be informative to find out what psi they're rated at.
Jake
Safety Car
Joined: Sep 2003
Posts: 3,692
Likes: 5
From: Hayward CA
Originally Posted by JAKE
All injectors aren't rated at the same pressure. The ones that come in our cars stock from the factory are rated at 43.5 psi. I believe the Ford injectors are rated at a different value, so it would be informative to find out what psi they're rated at.
Jake
Jake
From my old Mustang days, Ford injectors are rated at 38-39psi
Melting Slicks
Joined: Oct 2000
Posts: 3,426
Likes: 4
From: Heidelberg PA
Cruise-In V Veteran
Just curious, are they the 22's. I have a set I tried in my car and no matter what we did the car would not run worth crap. I put the Ford 24's back in and she ran like a raped ape!!
Did you add anything electrical to the car since the upgrade? If you did - disconnect it and test. I had another incident where the electrical pull was to much on the system and the ecm was dumping fuel. These cars can be finicky at times.
Good luck.
Did you add anything electrical to the car since the upgrade? If you did - disconnect it and test. I had another incident where the electrical pull was to much on the system and the ecm was dumping fuel. These cars can be finicky at times.
Good luck.
Burning Brakes
Joined: Nov 2004
Posts: 781
Likes: 0
At only 1500 RPM, I would have to say timing issue or plugged exhaust. Double, and triple, check all of the distributor/timing related settings and functioning. Check rotor phasing, confirm timing mark accuracy, amount of active advance, etc.
Pro
Joined: Mar 2005
Posts: 746
Likes: 0
From: Rochester PA
It's retarded too much, period. I had the same problem on a Nova SS I used to have. The same bank as yours got so hot, I could have stuck a screwdriver through any one of them. Advanced it til they quit glowing, which ended up being over 4*'s more than called for, but not by THAT engine. I think each engine has it's own "personalty", to a degree (no pun intended).
Rich K
Rich K
Racer
Joined: Mar 1999
Posts: 292
Likes: 0
From: Vienna VA
Mine also glows when the car is sitting and I hold the RPM to 1500. I worried about the same thing at one time. Even replaced the injectors, spark plugs, and wires. Timing and fuel all checked out. Air/fuel checked out slightly rich on the scanner.
However, the headers are not glowing after spirited driving, so I am not worried about it.
I suspect that the differences in header tube temperatures relate to the intake manifold. My miniram is not known for having great air distribution.
However, the headers are not glowing after spirited driving, so I am not worried about it.
I suspect that the differences in header tube temperatures relate to the intake manifold. My miniram is not known for having great air distribution.