Side pipe temperature

tommyboy · #1 (**permalink**) 07-17-2003, 11:38 AM

Has anyone measured the temperature of thier sidepipes, where they exit the fenders upto about 24 inches back ? Mine seem to be hot enough to blister the paint where they exit the fenders. I only have 18 total miles on the car. I've been out on a couple of test drives. The first test drive I knew I needed some additional adjustments. When I got back to my shop I got out of the car to put my fans on the sidepipes but before I could turn on the fans y some minor paint bubbles were starting to appear. My initial timing is at 18 deg and my total advance is 36-38 deg. I'm running 48IDA Webers. All the carbs are properly synced with correct fuel mixture adjustments and jetting. Engine oil and coolant temps are in the normal operating ranges. My second test drive proved to be much better after some tweaking. While being relatively easy on my test drive, knowing I still have to break in the engine and clutch, the car sounds awesome and has some very serious power. My car is Superformance #1593 with an aftermarket Dart 427cu.in. stroker, roller valvetrian, AFR 205 heads, MSD ignition with a 10.2:1 compression. I plan on checking the sidepipe temp with an infared pyrometer as soon as possible but I might have to drive around with two extra fans and an extension cord!! What would be a typical temperature range at idle and under some heavy loads ? How hot can PPG paint get before damage ? I also have plenty of clearance between the pipes and the body in all directions. I also entertained the idea of installing some adhesive backed heat barrier between the pipes and body if all else fails and I could make the installation look good. I will be up at Road America this weekend for the Vintage Car races and hope to find some answers !

Mr.Fixit · #2 (**permalink**) 07-17-2003, 12:13 PM

How much run-time does your engine have?
New motors often run very hot, header glowing hot, for the first 10-40 minutes. The oil and water don't get hot, but the EGT sure is up there.

tommyboy · #3 (**permalink**) 07-17-2003, 12:17 PM

My total engine run time is about 1/12 to 2 hours.

Mr.Fixit · #4 (**permalink**) 07-17-2003, 12:36 PM

How do your spark plugs look?

tommyboy · #5 (**permalink**) 07-17-2003, 01:24 PM

Spark plugs are fine, Tan to slightly darker. I have not run the car at WOT yet . Most of my driving has been light accels upto 3000 rpm or so. The idle circuit on the Weber 48IDA's will take you up to about 3000 rpm then you transition over to the mains.

Mr.Fixit · #6 (**permalink**) 07-17-2003, 01:34 PM

just making sure you aren't too lean, that will spike the EGT.

How far off the body of the SPF are your pipes, (especially the primaries)? Sometimes these things need spacers. Are the pipes painted or ceramic coated? If they are just the regular SPF high temp black paint, they will turn greyish if very hot, like their headers do. You aren't the first guy to blister the paint next to the sidepipes, but it is usually only that hot during the break-in of the motor, not like that 1.5 hours later. Of course, if you blistered the paint right away when the motor was super hot, how would you now know that the EGT has gone down to acceptable levels? I suppose you need an IR pyrometer and another cobra to compare your readings to.

tommyboy · #7 (**permalink**) 07-17-2003, 03:08 PM

I can slip my flat hand(about 1.0-1.5 inches) between the body and the inside edge of the sidepipes all the way, front to rear. There is a minimum of 7/8 inch clearance at the top, front and bottom of the sidepipes to the body and over 1.5 inches of clearance from the rear of the sidepipes to the edge of the body at the exit hole in the fenders. The pipes are jet hot coated black. Once I get a IR pyrometer I will definately know more. Until then I will just have to be carefull !

Double Venom · #8 (**permalink**) 07-17-2003, 06:11 PM

Tommyboy.

For a little comparison our DV's, (Viper powered) Cobras run around 875-1125 approximately five inches back from the collector. We keep a half inch clearance and never have a problem with paint blistering.

I would think a solid guess of 650 to 900 on your car would be very close. Sounds like it simply needs a little more breaking in

DV...

Lynn Johnson · #9 (**permalink**) 07-18-2003, 09:11 AM

Tommy - check with your Superformance dealer and get a set of stainless steel heat deflectors. Easy install and they cure the heat problem at fender exit.

Have them on mine and they work well.

Lynn

10Mike · #10 (**permalink**) 07-28-2003, 08:24 PM

read my private message