Just installed a 4-2-1 Megan racing header on my car and it feels as if i loss a lot of power and can hear a leak somewhere near the bottom where it connects to the cat. Can this cause a loss of power? Or are they just shi%y headers?

 

A bad exhaust leak can couse a very slight loss in low end, Header on a honda changes low end a little as well

 

thanks . yeah i think the leak is coming from near the radiator in that area. i don't think that a leak near the cat would be a problem because i heard that some people run that area disconnected to gain more hp.

 

is your megan header 2 pieces or one piece design. if 2 pieces design. the gasket that goes between manifold to down pipe has blown. this is very common for megan header and what i did is i bought a exhaust material sheet from local auto parts store and cut it .it works better than megan's gasket.

 

It's a 2 piece. I bought it off some kid for 10 bucks. It originally had cracks on all 4 of the piping that connected to the engine at the top but i had it welded. I dont think that has anything to do with the loss of power but i do feel air coming out between the down pipe on one side. I probly need to tighten on of the bolts down a little more. Wish i had a compressor to make things easier. The o2 seems like it's not screwed in all the way but thats as far as i can tighten it. I don't think it has anything to do with that. But i'll try and tighten the bolt and i'll let you guys know if it fixes it. thanks!

 

could a leak near the cat cause loss of power ? i don't think i used a donut. but i don't know if it can affect performance.

 

I've had luck using Permatex Copper on exhaust connections in the past. You can try getting a higher quality gasket (Megan gaskets are garbage), then put a little bit of the Permatex on each side of the gasket. You can even put some around the gap once you bolt the two pieces together.