high exhaust temp on #1

p2164 · Posted: Sat Jun 07, 2008 9:37 pm Post subject: high exhaust temp on #1

I was going over my throttle body injected 427 which is controlled by a tec 2 using wintec2. I noticed that #1 header was different color than the rest so I put the IR temp gauge and it reads at idle at least 100F higher than the rest so I thought that if maybe a bad injector or got some crap in it, I pulled all 8 and checked them with 42psi and popped them several times, good stream and shape. So I put #1 injector in place of #4 and started the car. I check the sync on each cylinder and they are the same air flow but #1 is still 100F higher than the rest. Any ideas? Motor has 200 miles on it from new, and 100f higher at idle might be nothing but at full throttle could be real bad difference.

TimZ · Posted: Tue Jun 10, 2008 12:05 pm Post subject: Re: high exhaust temp on #1

p2164 · Posted: Tue Jun 10, 2008 5:07 pm Post subject:

Is there any big difference in the airflow available around the #1 header tube?

No, plenty of room and air flow around it.

What injector settings are you using - batch or phased sequential?

Phased sequential

Does the plug on that cylinder look any different?

Looks the same as all the others. I wish I had a portable exhaust temp gauge with a switch for different cylinders. 1-6 fire the same time #6 is cooler. Could be just the headers and the way they are bent, not sure but never the less I am going to keep an eye on it.

TimZ · Posted: Tue Jun 10, 2008 7:42 pm Post subject:

A couple more ideas - is there any valve lash adjustment that could be off and effecting valve timing? It's probably hydraulic lifters so probably not.

Does that cylinder show anything unusual on a compression test?

It's difficult to tell from your pic in the member's rides section - are those headers ceramic coated? Often the coatings are done both inside and out - maybe the inside coating is thin or nonexistent on that tube, allowing more heat transfer.
_________________

Information is not knowledge
Knowledge is not wisdom
Wisdom is not truth
-FZ, Joe's Garage

**nefarious** · Posted: Tue Jun 10, 2008 8:27 pm Post subject:

p2164 · Posted: Wed Jun 11, 2008 2:09 am Post subject:

It's difficult to tell from your pic in the member's rides section - are those headers ceramic coated?

Ceramic coated.

Often the coatings are done both inside and out - maybe the inside coating is thin or nonexistent on that tube, allowing more heat transfer.

Out side only, and good question about the valve lash and compression, I will check tomorrow.