Fill it with water, plug all the holes, and put it in the freezer. That works most of the time...but not allways, it depends on how bad it is.

AFM

be careful with the freeze method !!! A guy here at my local track over freezed his pipe so it was in the shape of a baloon when he took it out ...
Where do you have the dents on the pipe ?? i took a screwdriver from the back of the pipe where the manifold is attached and pressed out the dents !

When freezing the pipe a short amount of time can make a huge difference, so i always try and check it every 15 minutes or so to make sure it hasnt expanded too far

okay, i'll try to freeze the pipe but what do I use to plug the holes? tissue paper?

Get a assortment of cork plugs from a craft store. I have heard that some guys have to put tape around the pipe to hold the corks in.

To cover the stinger i use some cling wrap with an elastic band.....to cover the pressure outlet i attach a piece of fuel tube, kink it over, then zip tie it kinked.......then fill the pipe with water thru the manifold end and stand it upright

Is cling wrap the microwave wrap? so basically i find a way to cover the stinger so there wont' be any leak and make the pipe straight and fill it up with water to the top and put it in a freezer and check every 15 minutes i guess??

Get some fuel tubing and cut to small pieces about an inch long. Plug one end with 3mm screws. Use those as plugs.

yeah that's what I thought

so I can just leave the top open eh? the ( mainfold part ) Seal the stinger only right?

Yep thats right and also cover the pressure outlet for the fuel tank
Cheers

does this method just get dents out the side of the pipe, or will it actually push out a bent in stinger?? I'd like to see some b4 and afters shots lol

I'm thinking of doing the same thing to my paris pipe with a dented-in exhaust outlet. Why do you need to plug the holes in the pipe? If the water doesn't need to go into those areas, do you need to plug them?

so the water doesnt leak out