The original thread can be seen here:

http://web.camaross.com/forums/showthread.php?t=409452

The header primaries are glowing at idle, and at part throttle under no load.

Things I have checked:

Rockers - readjusted, set a hair past zero lash.
Timing - pulled timing cover off, timing is straight up.
Replaced opti - swapped a known good opti onto the car, headers still glow.
New plugs - no change.
Swapped coil - no change.

The car has a F.A.S.T. engine management system with an on board wideband, and the a/f is reading OK. I suppose the O2 sensor could be off, but I'd think the plugs would reflect the car running that rich. The plugs look OK, and have about 200 miles on them.

I'm thinking the cam was possibly ground incorrectly and the cam wasn't degreed (I bought the car with this setup) and the valve timing is off. It's also possible the valve job is garbage...I don't know who did the valve job, but if it was a bad job, the valves wouldn't seal, allowing unburned fuel into the primaries. I would do a leakdown test, but the car is still apart.

I'm contemplating pulling the heads off and going with a different h/c setup.

Any thoughts/help is appreciated.

 

as long as the heads are bolted to the motor, you can do a leakdown test

 

If I remember correctly, glowing headers have to do with the car run either to rich or lean. I would just get the car tuned.

 

You're timing advance might be set too retarded ... you really need to get a timing light on it NOW to verify that the commanded timing is what you're actually getting.

Have you had the FAST installed and working well before this mess? If not, then you need to focus your attention there. If the values that you've programmed in for your ignition timing are reasonable, check the setup parameters. Forgot the name of the parameter, but it's the one that tells the FAST box where the piston is (in crank degrees) when the optical signal is received. If this is wrong, your entire timing map will off! Don't assume that whoever you bought the box from has it setup correctly.

 

It's not like I just plugged the FAST in and started the car. I've done an *** load of reading and tuning. The crank reference angle (the setting I assume you're talking about) is set to 6*. This is what it says to set the crank reference angle to in the FAST manual. I've been through all the parameters and I believe they are all correct. Do you know enough about FAST to take a look at the tables and draw any conclusions? If so, I'll take some screenshots and post them up.

 

Yes, the crank reference angle was what I was refering to ... I *think* mine was set around 6*, but I've seen VERY different values for the crank reference angle on LT1 cars with a piggy back interface (vs. stand alone or splicer harness). What type of harness/interface do you have on your fast box?

So just letting it idle turns the primaries red? When it is idling, what is the commanded ignition timing at idle? Should be in the 17-22 degree range. If your timing checks out and the commanded timing is reasonable, the next set is to get a timing light on it to see if the commanded timing is equal to actual timing. I like to zero out the timing map so commanded timing is 0* (TDC), then adjust the reference angle so that my timing pointer aligns exactly with the balancer TDC mark ... this only works if you've installed a timing pointer and marked the balancer at TDC ...

Chances are you haven't installed a timing pointer. Another option is to advance the timing and see if the problem goes away. Add 20 degrees to your entire map and see if the problem goes away or gets better. Don't drive it like this!!! It will be fine just idling under no load, but be sure to just use this to verify that timing is indeed the problem. If the headers stop glowing, the next step is to get a timing pointer, find TDC, mark the balancer, and check to see if the commanded timing is way off from actual.

Finally, is this your first timing installing a timing chain/gears? I've seen somone who really knows their stuff put one in wrong before... Crank gear dot needs to be at exactly 12 o'clock when the cam gear dot is at 6 o'clock - if they aren't lined up EXACTLY, you're a tooth or more off.

 

The harness is the harness that came with the FAST system.

Idling will turn the headers a very faint red, you can just tell they are glowing. Bring the RPMs up to 2k and holding it there for about 30 seconds makes the headers glow bright red.

Commanded timing at idle is 30*. What, besides the crank reference angle being off would cause commanded timing to be way off from actual timing?

Here's a quote from the FAST manual:

"GM Optispark Ignition

This ignition system uses a fixed crank reference angle of 6 degrees. No calibration or modification of any ignition components is necessary."

This is about my 10th timing set install (I didn't install the timing set, just took the timing cover off to check previous owner's work). Never had a problem in the past...the timing gears are dot to dot.

 

If you're running the stand alone harness, then the ref angle is set 'good enough.' Sounds like the timing might not be the problem, although 30* at idle seems a bit high to me. If you can eliminate the possiblility of timing error using a timing light, so much the better.

What does your AFR look like? Keep in mind, with a decent sized cam, you are not shooting for the reported 14.7 anymore. If you haven't already, try bumping the tables down to 14.1-14.4.

 

AFR at idle is right around 14.0:1.

Another thing to consider: the battery voltage fluctuates between ~ 11.8 and 12.3. The car has a new battery and a new alternator. I'm starting to wonder if there is a bad ground, and the ignition spark is weak, in turn not burning all the fuel in the cylinders. I'd think with a new battery/alternator, the voltage should be in the high 12s low 13s.

 

Where are you seeing the 11.8 - 12.3? On the gage or actually across the battery? Across the battery with a voltmeter at idle should be about 14 volts. See what the voltage does just off idle. If it goes up you know the voltage/ charging idea is wrong.

Are all the primaries glowing?

 

I'm seeing the 11.8 - 12.3V from the FAST datalogger.