Side Pipe cutout clearance

[lnfletcher]

Trying to decide just how much clearance I need to keep from scorching the paint or other problems. How much does everyone else have?

[Igofastr]

Definitely more than that!!

Remember, you are not only trying to prevent scortching the paint, but trying to keep the motor from twisting the sidepipes into the body (Unless you have solid motor mounts, I guess). I would suggest at least 0.5 inches, and probably more like 0.75. On the left side, the pipes will come up, on the right side, they'll go down.

I don't have paint on my car, but I can assure you the pipes are pretty hot as they exit the body, and they do move when you put your foot in it.

[Michael C Henry]

I went with 1/2 to 3/4 of an inch and aluminum tape inside to the edges. If that isn't enough you can cut it back further with a grinder. Try it a little before painting. The dryer and older the paint the less likely to be affected. Still ,letting the engine run prolonged periods without air moving around is asking for trouble. Are you concerned with movement or heat?

[RedBarchetta]

If you can't shove your fingers in there to wipe down part of the collector pipe, then you don't have enough clearance. I think that's a general shade tree mechanic's rule of thumb (or was that finger?).

-Dean

[Art Burtt]

If the body is off of the car and the engines ,headers and side pipes are attached, rev the engine up and see how much torque movement you get then add a little!

[lnfletcher]

Sounds like 3/4 inch is the answer. I was concerned about both the movement and paint and what I have in the picture is just a rough cutout before I make the final cuts. I would think the movement would mainly be vertical and it could be closer on the front and rear of the cutouts.
I guess I was mainly asking how much clearance all of you guys have with finished cars.

[Rick Parker]

3/4" is the accepted dimension. The most movement will result when the vehicle is in gear under hard acceleration. Art described it pretty well.