Exhaust Pipe Crush ...Repair?

[King Speed]

I am just wondering if there is anyone with experience repairing caved in aftermarket 4-1 headers? I have several and if for no other reason than appearance, I would like them to be round. The stock pipes are not stacked on top of one another and provide additional ground clearance. Can these be effectively repaired for a resonable amount of money? Or... should they be scrapped? I have a 4-1-2 header and mid pipes that I would like to set up with upgraded mufflers, but the underside of the lower pipes are FLAT or Concave.

[gearheadE30]

Well, are they oval pipes? Some exhausts have an oval cross section in order to improve ground clearance, but I can't say I've ever seen that outside of some pretty serious track cars.

You can try to repair the pipes by installing rubber plugs in all of the end openings, with one of them having a Schroeder valve or something to allow you to pressurize the innards with an air compressor, and then use a torch (mapp gas is a little more effective than propane) to heat the boundaries of the bend and essentially pop the dent out from the inside. Note that this is actually quite dangerous, as it is possible to blow the pipe up, so try it at your own risk. Other than that, I don't really know of any way to fix them,

[GateKeeper]

a rod and a ball bearing on the end....this is the method I am going to try to get the dings out of my pipes

[King Speed]

damage

I like this set up... but low clearance has bashed the lower pipes

[OldVet66]

You won't get those dents out. You could cut them out and then weld a slightly larger diameter pipe over the hole, or you could leave them as they are. You will not really notice the difference. Mine are like that and have been for years. I sand blasted mine with a small hand unit and white play sand and painted them with VHT Flameproof.

[Agemax]

use the search! there is a thread on here where someone successfully removed the dents on his headers with the steel ball on a stick method

[GateKeeper]

look at the picture I posted....

has the headers and the steel ball on a rod at the bottom left of the picture..

and I thought a picture was worth a thousand words....

LOL

[Agemax]

look at the picture I posted....

has the headers and the steel ball on a rod at the bottom left of the picture..

and I thought a picture was worth a thousand words....

LOL

thats why i posted up to use the search function!

[jay66]

#1 on the air pressure and heat method. Used that on my dirt bike pipe and it was pretty smashed. About 30 lb of air and the acetylene torch and those dents disappear. It is a little spooky doing this but it works.

[bubby]

this can be dangerous

your gonna have to use 5 plugs and a boot you can put a pressure gauge on, using oxy acy or mapp gas geat up the bends from the outside in but it is verry important to watch your pressure as the air heats it will expand and the pressure will rise i have done this aswell with 2 stroke expansion chambers i try to use a fitting that has a pressure regulator you can set at 35 lbs be careful don't split the seems with too much pressure WARNING: THIS CAN BE DANGEROUS NOT ONLY THE FLAMABILITY PART BUT AS THE PRESSURE RISES THE PLUGS OR BOOTS COULD BECOME FLYING PROJECTILES i have also seen this happen so i try to take procaution not to point the plugs or boots towards any thing you dont want to destroy including the cieling of your garage (plug went through 1/2 in dry wall) this is what i have its a expansion plug and a piece of rubber hose with a end cap clamped inside it and drilled a hole for the air chuck and gauge then i set my regulator as needed thinner wall pipe will require less pressure then heavy duty pipe

[jay66]

Yeah DANGEROUS for sure, for a little extra protection I wrapped the plugs with some heavy gauge wire then cinched them up tight around various places on the pipe. Plus keep the torch moving, it wouldnt take long to burn a hole and have hot metal flying at you.