MGB: PIA exhaust install

I just got my Peco big-bore system to replace my disentigrated "free-flow" POS kit from Moss and it turns out its not going to just 'bolt up'

The exhaust manifold/header I got is not OE (weber) nor is it a pair of headers or oldschool mainfold, its somewhere inbetween. I think it's cast iron, and all three branches are long, going into a collector at the bottom.

This collector is flanged, the Peco system is a slide-over-and-clamp setup. The in/out pipes on my cat are welded on, and the flange joint between the cat and the header leaks..





should I just take my car and the peco stuff to a shop and say "do 'er right"? hell at that point I might as well return the peco and have a dual-glasspack setup bent up nice and tight

I cannot afford the matching peco header that would fit right together



crap

what you have is a steel header, not cast. note the welds at the collector. The collector gasket is pretty standard and can be easily replaced. I'd send bsck the peco and find me a good pipe bender to build a custom system out of aluminized pipe from the cat back, or a little farther forward if you can get rid of the cat. I'd use a turbo type muffler, you'll only need one.

hrm, deq in another year... last time i passed at like 1-2% of allowances, but w/o cat that'll probably be...200% of allowances?

Where did you get that header? My belief was that because of the siamesed center exhaust ports, the best header is a long center branch (LCB) one - basically the two outers are shorter, then they join forming two pipes which finally become one about where your three become one. I have heard, and believe, that the stock, cast, LCB sysytem is pretty good but if you have the newer "log" manifold, probably a good LCB aftermarket header will be good too. I know both Moss and VB sell them.

Good luck.

Dyno says the only header that consistently outperforms a stock manifold is the Peco.

My gut says that without the header, the rest of the Peco exhaust won't outperform a good setup by a competent muffler shop.

If my recent experience is typical, Meineke ain't it.

Send the Peco back! Without its hader its just a pipe & a muffler....

..then, get rid of the header you have...look at how the pipes come together at the collector...they're fighting one another & probably causing some serious backdraft....find an original exhaust system all way fown to cat & put 2"aluminized steel pipe woth a single glasspack behind it!

...your header is robbing power by its design! But, were it me, I'd look towards the rust repair you're`about to have to tackle!