I rebuilt my starter over the past week and took the car out on a drive tonight. After driving about 20 minutes, in the dark, I got home and was looking over the starter to make sure all was good.

While looking the car over, still running, I noticed that the headers were glowing slightly. It is only noticeable in the dark. Number 3-6 had a slight glow to them. Number 1, 2, 7, and 8 did not. During the day, this is not visible. I have Melrose LT ceramic-coated headers.

I don't believe the car is running lean. The timing is a little retarded. I've got a MSD controller and it was set at 6* retard. I turned that back to 0, but the headers still had a slight glow, again only visible in the dark.

Should I be worried about something or is this normal at night?

Do they have purpleish rust on the outside? I have a handful of codes right now: egr, lean, est. I've never looked at them in the dark, but I think that's why I'm getting the purpleish rust color on my headers. However, after 6 months, the purple has not spread at all or gotten any bigger.

soooooooooo...

Based on my 60% confidence level, I think it is normal and will stop after time.

EDIT: Saw you post on "the other site," and I've got $100 bucks on 2 "check your FSM" and one "if you use the search function..."

Andrew -

I don't have headers, so I'm not an expert. It's my understanding that if your headers are glowing it could be caused by unburnt fuel igniting in them, caused by timing that is too retarded. Can also be caused by too much fuel.

Good luck and keep us posted.

Matthew

It could be too much fuel. When cold, it definitely runs rich.

So, how do I adjust this?

Also, the car likes to run on 93 octane. This tank has 91 in it since I could not find a station that sold 93 the other day and did not have enough fuel to get to the normal gas station. Could this be causing this? I've just never noticed this before.

Too much fuel could be too large of injectors, increased fuel pressure, bad tune. Do you have a custom tune? What size injectors are you running in the 383?

Once you post up, I'm sure Mekanik will give you some good advice on injector size.

Matthew

It still has the factory injectors in it. The fuel pressure is 36 at idle and a steady 40 when under load.

As for the tune, I don't know if it is factory or custom. I'm thinking about purchasing some software to do this, but do not know if it is worth the price.

Wow, I'd wait for Mekanik to give some advice, I don't want to steer you in the wrong direction. I would figure with a 383 you'd need a bigger injector. He knows his stuff with that.

Matthew

I'm here!!! (insert captain America "Dun DUN DAAHHHH" here)

For a 383 build like that your injectors are quite small.

Here is a few things to chew on.

According to DRM they install a different fuel pump and adjustable fuel pressure regulator. Your fuel pressure looks okay, could you tell me what the pressure looks like with the engine off and the rails primed?

To do this just hook up the gauge, turn the key on (hear fuel pump come on, then go off) then tell me the pressure, and if it drops at all.

DRM also says it does "custom computer calibration" But it has no mention of using any larger injectors on their site.

To sustain the 470CHP that DRM claims, you need at least a 36lb injector. The stock LT4 injector is a 26.

Now also depending on how you are getting fuel enrichment for your nitrous you may need to up that even further.

Hope that helps!

Quote:

I ain't an expert either, and I say unburned fuel too.

You say you got an EGR code. EGR CAN be tripped by a vacuum leak. And a vacuum leak can prevent full atomization of the fuel, which means all of it might not be burned, which means glowing headers...

My

Thanks for all of the info and keep it coming! Sorry for the long post, but this might help in diagnosing a problem, if one exists.

I checked the pressure while not running and it is a solid 36 - 37 psi. I had some NGK TR6 plugs in it for a few hundred miles and they were very black, but these are cool plugs. I use TR55's and they are doing very well. When I look at the ground strap, they are very light in color, but the ignition system is what I believe is causing this. Right now the TR55's are set at .050. I do believe that the stock injectors are stock. Here is a picture of them, so if they don't appear to be stock, please let me know.

[IMG]http://i229.photobucket.com/albums/ee251/awheel73_photo/1996%20Yellow%20LT4%20Corvette/1996%20Yellow%20LT4%20383/MotorDriversSIde.jpg[/IMG]

The motor is not a stock DRM 480 package. The previous owner started out with this and added some really beefy parts to the motor. The only DRM work that remains is the machine work on the block. Here is a list of items added later. All of this info came from the previous owner.

Crank, rods, and pistons were replaced with an all forged rotating assembly. The pistons are ROSS and hold about 190 psi compression.

Cam and pushrods are Crane with lift of .555/.570. Don't know the other specs.

Heads have been ported, bigger valves, double springs, titanium retainer, and the flow is about 280. Crane Gold 1.6 RR's added.

Intake has been port matched to the heads and 58 mm tb. TB is 58 mm.

[IMG]http://i229.photobucket.com/albums/ee251/awheel73_photo/1996%20Yellow%20LT4%20Corvette/1996%20Yellow%20LT4%20383/ManifoldPort.jpg[/IMG]

[IMG]http://i229.photobucket.com/albums/ee251/awheel73_photo/1996%20Yellow%20LT4%20Corvette/1996%20Yellow%20LT4%20383/ManifoldPortCloseUp.jpg[/IMG]

[IMG]http://i229.photobucket.com/albums/ee251/awheel73_photo/1996%20Yellow%20LT4%20Corvette/1996%20Yellow%20LT4%20383/Manifold1.jpg[/IMG]

Ignition is MSD Dig 6 Plus Controller (Part 6520) with Accel Coil, and MSD opti.

Nitrous system, NX MAF wet system, FJO progressive controller, fuel pressure regulator switch, with bottle warmer. All the good stuff. Here are 2 picturs.

[IMG]http://i229.photobucket.com/albums/ee251/awheel73_photo/1996%20Yellow%20LT4%20Corvette/1996%20Yellow%20LT4%20383/MotorDriversSideNOS.jpg[/IMG]

[IMG]http://i229.photobucket.com/albums/ee251/awheel73_photo/1996%20Yellow%20LT4%20Corvette/1996%20Yellow%20LT4%20383/MotorPassengerSideNOS.jpg[/IMG]

Meziere HD electric water pump.

I'm beginning to think the car needs a custom tune. Is this something that I can do?

I just had the car out for a short drive. The car is running really well and after returning home, I looked the headers over. During the day, there is absolutely no glow present, only the ceramic coating color.

So, the glowing I saw at night may be normal, but I just had never noticed it before.

glad its running good, but I have small things to mention here.

Your fuel pressure should be higher. Your stock injectors will only flow 26lb at 43psi rail pressure.

The other is I still think those injectors are VERY undersized for what you are doing.

I would advise if possible to get the A/F , on motor and on nitrous. With those injectors I would be quite concerned about going lean and hurting something

What size injectors would you recommend? They really are not that expensive, so replacing them would be no big deal.

I don't use the nitrous setup. Can a tuning software change the A/F ratio's or should I take it somewhere and have them do this? I'm really new at using electronics to control the A/F ratio.

Thanks for all of the advice and feel free to point out anything that you think I needs to be changed. I did not set the car up like this and you will not offend me by making recommendations.

Hey, it's winter coming up and I need some projects to do in the garage!!

Maybe Anesthes can drop in and give a recommendation on injector size but yes, stock is wayyyyy to small, youre taxing those poor things.

If the motor is putting out the 470CHP that DRM says they do, then you will need a 36lb injector.

You will need to have the computer tuned for them tho.

I can do our rebuilt Bosch Design III in 36lb for $269 for the set, drop in, viton o-rings installed. Shipping is $11.60