lifted99GMC

iTrader: (4)

I was curious to see if anyone knows of any old style big block chevy headers would work with the 8.1L big block. Just by looking at the stock manifolds on the 8.1, the bolt pattern looks the same, but its been a while since ive seen an old style BBC and paid attention to the headers. I can probably pick up an old set of headers cheap and maybe with a few modifications make them work on my truck. Any ideas, suggestions, or types to look for? Thanks

Chad

02_2500avalanche

They will work but you are going to have to weld an in 02 sensor ports and an egr port on to the passanger side header and that thing is in a tight *** spot, probably the worst part about installing headers on this thing. I believe you are going to have to do alot of modifications to make them work and by the time your done it would have been worth it to spend the $630 on Stainless Works long tubes.

Alex

lifted99GMC

iTrader: (4)

O2 and EGR fittings i dont think will be too much of a problem, my main concern woud be clearance from hitting the underbody. It looks like there is PLENTY of room from the heads to the frame, but ill just have to do some looking around to see what headers will have long enough bend to them to clear the body. It may be worth 600+ bones to some instead of working a day or so trying to get some to fit, but i like fabbing up things, and the worst happens, ill be out about 50 bucks, a few hours of my time and just put back on the manifolds and get some headers that are made for it. I didnt think a set of MAC headers for an LS1 would work on my old 99 5.3L pickup, but they slid right in there with some minor massaging.

Chad

TieRod

Also the 8.1 is a tall deck. So the heads are set higher up and wider.

David Stiers

hello so did you find out if regular big block headers will work on a 8.1l ?

RedXray

He's still working out the small fitment issues. Check back in sixteen more years, I'm sure in 2037 he will update this thread.

terravast4

iTrader: (25)