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So, I pulled the heads on my 1980 L-48 as part of a partial rebuild. As often happens, the layers of the onion are being peeled. After removing my exhaust manifolds to remove the heads, I noted that the car has a stock exhaust setup, the 2 to 1 to 2 exhaust pipe restrictive system.
What are some options for an easy, do-it-yourself type conversion from single to dual exhaust? I'm looking for something quiet as often as possible that meets the dual exhaust upgrade.
I know there are many posts on this topic, and I've searched them. I didn't see any that addressed these two concepts, those of quiet rather than performance-oriented and easiest way to go dual from factory 2-1-2.
Here in SC, there are many trucks on the road. A select few have exhausts that sound like they've had the catalytic converters cut out and stolen from them. Makes an unholy noise that rattles your teeth when they drive by. Loud.
The stock exhaust on my 80 L-48 makes a nice burble at idle, doesn't rattle teeth when cruising, and makes a nice growl when accelerating. Quiet.
There's nothing quite like the burbling exhaust note made by an American V8 sports car engine, and I would never want to suppress that. Just want to maintain a little bit of civility until the pedal is floored.
All ideas for a duel exhaust install for the DIYer are always welcome. I'm guessing it requires some kind of cross member update, but since I can't weld and can't put the car on a lift at home, it'd have to be some kind of bolt-together solution.
You can use the old manifolds and run 2.5" duals in same path as stock 2/1/2 . Delete the cat if you can . Or you can buy an older crossmember with the holes for exhaust and oblong the mounting holes on it to bolt to your frame and go straight back.
Buy headers, change the crossmember, go 2.5" exhaust, pic a muffler and put in a X or H pipe after the crossmember. The X or H pipe will take out that annoying truck sound.
It's an auto. I forget to mention that sometimes in my posts. I'll be sure to add it from now on.
L82Dude, I like those ideas about the stock path and the H pipe. I always wondered what they were for. Did some quick Google research and learned. They make a lot of sense. Thanks for the info!
St. Jude Donor '09-'10-'11-'12-'13-'14-'15-'16-'17-‘18-'19-'20-'21-'22-'23
Corvette Central has a dual system that bolts up perfectly to your exhaust manifolds and routes the pipe in the correct manner. If I remember correctly though, I had to use one designed for an earlier car (mine's a 79).
Give them a call, they're usually very knowledgeable about what works on what.
It's an auto. I forget to mention that sometimes in my posts. I'll be sure to add it from now on.
L82Dude, I like those ideas about the stock path and the H pipe. I always wondered what they were for. Did some quick Google research and learned. They make a lot of sense. Thanks for the info!
Blaine
I don't remember if the tranny crossmember is welded in with the 80 automatic.
I don't remember if the tranny crossmember is welded in with the 80 automatic.
on automatics, the crossmember is bolted in, or you will never get the tranny out. 4 spds have them welded in place.
I have a 80 l82, was auto, changed to 4 spd, used older crossmember with holes for exhaust <don't know year of it > was from an automatic car, but it bolted right up to super T10 tranny, just had to oblong holes where mounted to frame.
on automatics, the crossmember is bolted in, or you will never get the tranny out. 4 spds have them welded in place.
I have a 80 l82, was auto, changed to 4 spd, used older crossmember with holes for exhaust <don't know year of it > was from an automatic car, but it bolted right up to super T10 tranny, just had to oblong holes where mounted to frame.
The 80 4spd is a bolt-in crossmember from the factory, not welded. The crossmember I used for my dual exhaust was from a 74.
Well, after coming home from the awesome trip to NCM, I did some more review of the documentation that came with my Vette and inspected the exhaust system. It turns out, I don't have a stock system, or at least part of it isn't stock.
My docs suggest that I have Hedman Hedders installed, and inspection of the mufflers shows they are Hooker Super Competition mufflers.
The thing that led me to believe it was a stock system is the 2-1-2 layout where the headers go to a single Y-pipe and back out to dual mufflers. I've attached some pictures here to show you to what I am referring. It now makes me wonder if the Y-pipe section is stock and the headers and mufflers are (obviously) aftermarket.
So, I guess my updated question is... how do I go from this 2-1-2 system to a true dual exhaust by just replacing the Y-pipe section? Custom exhaust work at a shop? Is there a vendor product that will do this? I'll still sandblast the headers and do things right either way.
Do you have a muffler good shop in your area? Tell them what you want they can custom build it. Get an estimate. You have most of what you need already, mufflers look good use them. Go buy a 2 1/2" X pipe they help with some toque.
good luck
I have the "off road only" dual system designed for '80 corvettes. The turbo mufflers I have on there now are still just a little too noisy for me. I am considering trying stock mufflers from a '74 as they were designed for use without converters. I want it QUIET.
All ideas for a duel exhaust install for the DIYer are always welcome. I'm guessing it requires some kind of cross member update, but since I can't weld and can't put the car on a lift at home, it'd have to be some kind of bolt-together solution.
Thanks!
Blaine[/QUOTE] Im wondering how someone can do a exhaust system replacement with out lifting up the car You could still use that 80s style 2 into 1 back to 2,, use 3' pipes, NO CAT, less restrictive if thats what your looking for, i add depends on your budget really
LS-5 454, Hooker Super Comp, Pypes full exhaust with X pipe and mufflers in the stock location. Works great and tucks up tight to the underside. Only thing I had to do was make the collectors fit to the X pipe, just in front of the cross member Not too loud, but not quite by any means.
And I did all this in my garage on jackstands. Not hard at all.....
Last edited by USAFVeteran; 04-14-2017 at 12:22 PM.
04-07-2017, 06:28 PM
Easiest DIY Dual Exhaust Conversion From Stock?
Im wondering how someone can do a exhaust system replacement with out lifting up the car 
You could still use that 80s style 2 into 1 back to 2,, use 3' pipes, NO CAT, less restrictive if thats what your looking for, i add depends on your budget really
I think you just opened a can of worms ya can't close ,lol,lol, 