B & B Customs

I'm replacing my stock (mangled up) 08 LS3 NPP with an 08 Z06 NPP axleback.

For starters, I know that its a 3" compared to 2.5" (correct me?) axle back. I plan on buying OBX headers for this car, since I had such great luck with them on my 06 C6.

Now - when I go to look on the bay full of electronica, I see them advertised 05-08, and 09-13.

Whats the difference between an 08 and 09 LS3? I need Z06 fitment headers to match the 3" NPP axle back. So... Bottom line, what year/fitment headers do I need to get to make this work?

B & B Customs

Also - if there is a supporting vendor selling OBX, let me know. Ain't tryin to break no more rules on here - the info is WAY too valuable!

RicK T

Yes, Z06 is 3", up to the muffler then necks down to 2 1/2 into the muffler.

In '09 they changed the angle of the passenger side pipe exiting the X-pipe. It's only something like 5 degrees but they don't line up directly.

So if you buy an '09+ setup you need the '09+ x-pipe, not an '08 x-pipe. If you get an '06-'08 setup then you need the earlier x-pipe.

Or, if in a bind, any competent muffler shop (or maybe you) can heat the x-pipe and bend it to mate up properly.

B & B Customs

Thanks! Well, the headers come with an X-pipe. So basically, I DO need to get the Z06 headers and x-pipe to fit the Z06 mufflers? Year wont matter, as long as?

HOXXOH

Another choice is get the headers/X-pipe to match the current '08 LS3 2.5" pipe size. Then cut the 3" pipes off the Z06 bi-mode mufflers about 3/4" from the can. Cut the 2.5" pipes off any pre-09 mufflers as close to the can as possible and weld them into the Z06 bi-mode mufflers.

That way you have no interference or angularity issues with over-the-axle pipes and you keep the velocity of the exhaust gasses higher. If you ever need or choose to buy any other mufflers in the future, including another '08 NPP set, they will be a simple bolt-on rather than needing to modify them to fit.

If you plan to go FI in the future, then simply buy the OBX header/X-pipe for a '08 Z06 and you'll be done, assuming you don't have a clearance issue with the 3" over-the-axle pipes if the car has an A6 trans. Keep in mind that you'll have less power with the 3" pipes than the 2.5" while N/A.

haljensen

Z06 headers and Z06 mid-pipe require Z06 mufflers unless you want to cut and weld.. If there are two different Z06 muffler setups from your supplier just make sure they send you the one to match your mid pipe.