Topic: stock exhaust

[Tin Indians Rule]

Good documentation Burd. Thanks for posting.

[Justin]

Justin, Im not an expert by any means on the W72 cars (or really any of them) but I can't ever recall seeing a factory splitter after the catalytic converter going into dual floor board mufflers. That piece must be custom and I'd guess any qualified muffler shop with a pipe bender could duplicate it.

I's guess the y coming out of the manifolds was a custom piece too???

it was stock..... y out of manifolds was stock as well......

my question is.... why are you going back to stock exhaust? CA law? otherwise you could run duals with newer catalytic converters and pass the emission test.... just lean out the carb the day you have inspection.....

I have to go back to stock setup for the visual inspection. I already currently have long tube heads to a 2 1/2 inch x pipe that goes into two flowmaster 40's. The mufflers back can stay. I even needed stock setup in PA but I registered it to a friends address in a county where they didn't even need to run cats.

[Justin]

Heres my orig crossover pipe, very thick steel, and here is my orig cat, and the cat hanger brkt.



I didn' have this set up, this was the "dual exhaust" for 78, I had the muffler w/ 3 holes in it.

  Burd. That is exactly what i am looking for. Just go ahead and send me a PM and I'll give you my address.

  No but seriously. Thank you for that documentation. Now I know I am not crazy. Is there anyone who makes that these days? Also what about a cat that is that style? I can use any new cat I want. It doesn't have to be the original. Just as long as it has "CA" stamped into the sheet metal. Magnaflow make a universal cat that is 50 state legal that I may use.

[Justin]

Just called the local dealer here and he checked the part numbers and said they are correct for 1978 Firebird with a Pontiac 400 but said no dealer in the country has one. He said sometimes you'd be surprised of what certain dealers got stuck with but it's a no go on the bracket or pipe.

  Then he asked me to bring the car by when I got it on the road because he would love to see it and he has always been a TA fan. LOL.  Good times.

[Burd Turd]

Between the exhaust, the efe valve, those bad ex manifolds, and no curve in the dist, it's amazing they ran!  I yanked the cat first in 79, then a dual exhaust, but they were only 2" tubes, that made a difference. For $10, you could buy a TEST TUBE, to test the cat to see if it was plugged. why I ever saved that orig crossover I don't know why!
I saw a NOS cat in the last year either on ebay, or in the POCI mag, they are out there, don't forget the Camaro's got some of the same parts too. Look on NASTY Z28 too.

[Justin]

here are the screen shots from the John M Witzke-W72 Performance Package Historian.

[hada76]

i would be surprised if the guy doing the visual would know exactly how the pipes should look. hes prob just looking for a cat(s). you prob would have to loose the headers though

[Burd Turd]

Out west there are still some yards w/ non rusty cars, in Phoenix alone i saw some when we junkyarded out there, i would think you could buy the rest of the system aftermkt.

[Justin]

I have to lose the header and the x pipe. They have the same pictures we are looking at. the guys here with the R.A.R.E exhaust manifolds do get by with them because they look stock enough. I'll probably have to buy down pipes and buy the 3 bolt flanges then take them to a shop and have a crossover pipe made then flared at the cat section.

[Burd Turd]

Maybe have Oldschoolblubber look for you in the desert.

[Burd Turd]

Maybe a trip to SEMA, and have the pro's show you what parts are avail!

[Justin]

Maybe a trip to SEMA, and have the pro's show you what parts are avail!

If those are the pros I am supposed to meet then sign me up. I just need something to get me by for now. As soon as the inspection is done I am throwing my x pipe back in. Even Katees aunt who is a smog tech said just get it through the visual and put your x pipe setup back in. The inspection is once every 2 years so its not like it will have to happen often.

[Burd Turd]

That is such a drag!! I remember the testing days, Mine always passed w/ the cat off, it wouldn't now though, after the re-curve and re-doin the carb w/ a NUNZI"S perf kit, but the air is perfect up here in Michigan!

[Tin Indians Rule]

I found an old supplier/dealer with 5 of the headpipes showing in inventory. I didn't call to have him check but they are listed as 10003452. PM for contact info if anyone just has to have an NOS headpipe. I'd bet a muffler shop could bend one cheaper than shipping for a NOS piece.

[Justin]

got my Y pipe. So freaking happy. I will just use this to have a shop make me one. They should be able to bend me the rest of it based of the info they have right?