I hav an 03 v6 and want to install mac lt headers. I have a true dual exhaust with flowmaster 40s and no midpipe. The piping is 2.25. Would the headers just bolt on or would i absolutely need a shorty midpipe, and is it a problem that the piping isnt 2.5???

 

You need the mac h-pipe and you'll need to have some cats added, I recommend Magnaflow cats. The headers are easy to install, even easier if you remove the starter and upper intake. If you cn get away with it, deleting the EGR will make things easier as well, you'll need a tuner to turn the EGR system off.

 

But wouldnt i need a 2.25 midpipe to fit my catback? i dont think that will fit the headers since they are 2.5.

 

The MAC h-pipe botls up to a GT catback, I'd hop on their site to see the diameter, I can;t remeber what mine is offhand, but I'm pretty sure it's 2.5"

 

i dont hav a gt catback. Its just flowmaster 40s on 2.25 piping that was made at a shop.

 

The MAC H pipe is 2.5" in diameter.

 

sounds like you might be needing to get a catback

 

you can get your stuff modified at a shop to bolt up to the headers or the H pipe most likely but i would recommend getting the new MAC H pipe and a new catback that is 2.5, if you dont you will be restricting your exhaust and wont get your full gains

 

So couldnt i just get a shop to modify the piping to 2.5 right where it meets the header and not have to get an H pipe or catback? And 2.25 isnt restricting at all for a v6 it came stock on all v8's.

 

How about just do whatever you want and don't listen to everyone telling you what is right.