[dwmilton]

Hi all, I'm new to your family. I'm prepping to buy a 78 Pontiac G-body, and am analyzing (emphasis on ANAL) what to do about the exhaust. Money IS an issue, but I can take my time on this, buying a piece at a time if needed. The car has a 301, but will get a 400 shortly after I buy it. There is no catalytic on it presently, so that's not a problem. I'll try to "Reader's Digest" my questions: single, full dual (with X), or single-to-dual (split dual?) system?, headers or manifolds?, what's best for the $$? Is it easy/cheap to have a local muffler shop (or me) bend/cut the crossmember for duals if I do go with headers? If I keep it a single exhaust, would I be giving up much by running a 3" system, rather than 2 1/2" duals? I want the car to have good power, but look mainly stock to a casual observer, and keep the sound reasonable. On one hand I'd love nothing more than to just buy an aftermarket crossmember, a set of headers, and a full "Pypes" system with the GN type exits; however I don't know the money could be justified over a big single system, or a split dual system, or "modifying" the OE crossmember. I hope this all makes sense, I really value any input you guys and gals can offer. Basically I'm trying to justify the expense of each part of the system.

[dwmilton]

Hi all, I'm new to your family. I'm prepping to buy a 78 Pontiac G-body, and am analyzing (emphasis on ANAL) what to do about the exhaust. Money IS an issue, but I can take my time on this, buying a piece at a time if needed. The car has a 301, but will get a 400 shortly after I buy it. There is no catalytic on it presently, so that's not a problem. I'll try to "Reader's Digest" my questions: single, full dual (with X), or single-to-dual (split dual?) system?, headers or manifolds?, what's best for the $$? Is it easy/cheap to have a local muffler shop (or me) bend/cut the crossmember for duals if I do go with headers? If I keep it a single exhaust, would I be giving up much by running a 3" system, rather than 2 1/2" duals? I want the car to have good power, but look mainly stock to a casual observer, and keep the sound reasonable. On one hand I'd love nothing more than to just buy an aftermarket crossmember, a set of headers, and a full "Pypes" system with the GN type exits; however I don't know the money could be justified over a big single system, or a split dual system, or "modifying" the OE crossmember. I hope this all makes sense, I really value any input you guys and gals can offer. Basically I'm trying to justify the expense of each part of the system.

[screamingchief]

crossmember heredual crossmember g-body
headers here IA g-body header
and for exhaust here pypes link
or here torque tech link
manifolds here manifold link
or from the sites sponsor performance years,and pypes has the downpipes that would be needed.
a budget option here exhaust wise budget exhaust
might need a little tweaking as its designed for sbc.
as is this dynomax sys
these are just a few of the options available sure there are more
I know it not all that cheap so I am going to add a few low dollar options,here:
with stock manifolds here stock down pipes
If you were to use the pypes down pipe to mate to one of the low dollar systems listed with the jegs crossmember I would think you could come up with a decent exhaust that should do reasonably well for not too much $$$$ I don't know what type of exhaust note you prefer fully but feel that the dynomax super turbo should be a pretty good compromise on price/perfomance basis.good luck and hopefully more folks will jump in on this.

[screamingchief]

I am not sure which headers fit well as I have not done this swap so hopefully someone else will give you an idea on that,and what would be the best cost wise.And most exhaust shops can do a decent job on exhaust but virtually all use compression benders which tend to reduce flow so even if you just invested in some mandrel bent tailpipes and downpipes you surely would be ahead on getting good exhaust flow.I know it can be a difficult area to decide which is the best way to go, so again good luck and hope all goes well

[Bull]

Welcome to the group. We've got a good bunch of people here, both knowledgeable and friendly. What type of '78 are you buying? I just purchased a '78 Grand Lemans a couple weeks ago, and as you saw in my other post here, need a new exhaust as well because it failed inspection. My car currently has true dual exhaust even though it only has the stock one-hump crossmember. A previous owner had both pipes routed under that one hump. It is an option if you do not care much about looks. After getting walloped with the Midas quote, I've been thinking of installing the G-force crossmember and then installing my own ehxaust system, but I'd spend as much if not more than the $500 plus that Midas quoted me. I've also thought of going to NAPA and seeing if you can buy stock pieces, from the manifolds back, to install a split-dual system (y-pipe into one converter, then splitting into two mufflers and two tailpipes). The choices are driving me insane, as is the fact that I have a crappy place to work on my car in the frozen wasteland of New England winter, but anyway, screamingchief has given us both some good advice. Let me know what you decide to do. If your car is a Lemans, send me some pics!

[dwmilton]

The car is a Grand Am Landau. The Jegs crossmember looks nice and inexpensive. I'm considering a full sleeper setup on the car...single exhaust, whitewall tires...LOL. I'll have to see how things go but I'd prefer to go "whole hog" with headers, crossmember, full duals if I dont do the big single system. Was thinking 3" all the way on the single, unless only a 2 1/2" tailpipe will go over the axle. I have some header/manifold questions, but will start a new thread for them, once I do some research.

[Bull]

I didn't know Jegs had a crossmember for that application. I'll have to check the catalog. Do you have the part number handy? I was looking at the one from G-force, and it is around $200.

[dwmilton]

Sure, here's a link:

http://www.jegs.com/cgi-bin/ncommerc...09&prmenbr=361

It states it's for a TH350/SBC combo in a G-body, but from my research, all of the G-bods would be the same, except the TH200-4R cars...or if ya use a longer TH400. For us with TH200/350s, it should be good to go. I don't think the engine (SBC, BBC, BBO, BBP, BBB, etc) makes a difference with the crossmember so long as you mount the engine properly...not back-setting it. A great deal at about $130!!