just bought the megan headers and i heard some complains of the installation. So i wanted to know what size botls will i need so that the header can fit right on. And what can i do to avoid cell leaks and my check engine light to go on. Any advice get back to me ASAP I REALLY NEED UR HELP!!!!!!!!!!!!!!!!!!!!!!!!!!!

 

...cell leaks?

 

first of all, you re-use all existing bolts from the stock headers and downpipe. get a new exaust manifold gasket if your megans didn't come with one. you should not be getting and Check Engine Light issues, just be careful that you dont break the o2 sensor when getting the old headers, if i remember correctly, it's either on or right after the downpipe.. check the tech section for a header install and look at the pics, it's been so long since i put mine on, but all the headers go on the same way.. pics are universal for all brands. also when you take off the stock header, check the thinmetal heat shield, you wont need to re-use that.
also, when the install is complete, disconnect the battery for a minute and then re-connect it.. that re-sets the computer... start the car and let it run for 5 min at adle, while you enjoy the new tone... then go drive it after it has warmed up and the computer has made the corrections for the new higher flow headers.

 

well when i put my headers on my car i had a small like not bad...but no cel came on... and its sounds louder when im next to stock scion