lobwedge

JUst took the cat and stock system off and ran 2 1/2 pipe to two dynomax mufflers and bypassed the smog pump and wow what a improvement in overall driveability low end out put is great mid range response is now great its more like i thought this car should be if your thinking about it youll love it
Take care
Wayne :flag :grouphug:


[Modified by lobwedge, 1:47 PM 3/1/2003]

Metal Wulf

:cool: :thumbs:

Desertdawg

On my 82 I just put on a set of Borla's, and (shhh! empty'd out he cat). I do have to say that the throttle response is a bit more lively now. :cool:

Dalannex

Sounds like my setup. I love it. I'm trying to get my dad to go that route on his 80, but why spend money replacing an exhaust setup that's not rusted out? :rolleyes: He's a little tight with the $$$. :lol:

-Justin

Ghostrider

That ain't nothing. Try a ZZ4 with Hooker headers, no cats, Borlas and a 700R4. The 80's C3s were severely underpowered.

Rich80

I'd dp it right away but how do you get the car inspected? I drive less than 5K a year so Im emmissions exempt, but does that mean they will put an inspection sticker on for me? :smash:

BSeery

:withstupid:

I have the ZZ4, 700R4, Headman headers and hi-flow cats and no mufflers at all.

Now I just need to invest in rear tires.

Jman

Yep! I just had a hi-flow cat, Flowmaster Delta 50 mufflers, and all new 2.5in exhaust system put on my 82, and I love it! I love the low smooth sound of the flows! The delta 50 series are great. They are pretty quiet, but the tone is perfect. Exactly what I was looking for! :cheers: I'll psot some pictures next time I get it up in the air.

jaybird81

I am planning on going with a true dual exhaust getting rid of the cat and also taking off the smog pump. I wasn't sure what kind of difference it would make but I guess its worth it. I wasn't thinking about putting headers on, lobwedge are you running headers or not?

UKPaul

Jaybird81,
Go for it! Changing to 2 1/2" duals was probably the best thing I did on my '81. I've seen figures of a 25 - 30HP improvement by going to duals with no cats. I don't know if that's true but you'll feel a big improvement :D I'm still running the stock manifolds, but now have a set of Headers waiting to go on.
:cheers:

Dk Met Grn 80 L82

When changing to true duals, did you have any issues with the bolts at the exhaust manifold or did you just cut the pipes near the manifold and weld?

Ganey

See Why Exhaust is problem for HP on 75-81
what many refer to as my Exhaust topic. http://www.corvettefaq.com/c3/ganeyexhaust.htm

Dk Met Grn 80 L82

Ganey, WOW, great old post information on exhaust performance boost.
I am considering loosing the CAT to either a high flow CAT, straight pipe, or true duals later this spring. I saw a true dual system from Mid America, does anyone know if this fits up OK on an 80? Does the crossmember need to be changed to accomodate the pipes? I recently put Magnaflow SS straight through design mufflers on and felt an increase in HP just from that. :chevy

UKPaul

I've fitted the MA 2 1/2" true duals to my '81 & it was the best thing I've done to it (so far). Even with stock mufflers the power increase was really obvious & with straight through Monza mufflers it's even better, but swapping the mufflers didn't have such a big effect as the duals alone did. The d.side pipe went on really easily but the p.side made the muffler sit too far outboard & was easily modified with a hacksaw (it was only about 1/2" off, but I'm a perfectionist about getting symmetrically positioned mufflers).
No mods were needed to the x-member as both pipes go down the p side & pass under the section that the original pipe did.
If you're after every fraction of a hp that you can get then these pipes aren't perfect due to the unequal lengths & the bends in the d. side pipe. For normal street use I'm very happy with them.
Even more power can be gained by fitting an "X" or "H" pipe to balance the system. Without an "X" or "H" pipe fitted, setting up the idle speed/mixture is a lot easier (just sit behind the car & you can hear which side needs tweaking!). Without a balanced system you will get popping in the exhaust when you shut down (but I like that :D ). One other thing is that yesterday I took mine off (fitting new tranny + Headers) & it came apart really easy.
There's a LOT of stuff in the archives on these pipes & some people like them, some don't. For the price I reckon they're very good (but I might change my mind when I try to hook them up to Headers :lol: ).
I hope the '80 & '81 have the same exhaust sytems (can't remember). If they don't then please ignore most of the above!
:cheers:

hunt4cleanair

Anyone want to sell the nuts and bolts off the cats?

Ganey

Thanks. Surprised me when some called it the best topic ever.
Sounds good. The dual ex. crossmember used through 79 is rec.
They should have duals for your crossmember which could be setup to drop the ex. easy.

projectL82

i recently re-did about everything concerning the hp of the car and i love my true dual exhaust. as for the popping many experience with no H or X pipr i actually haven't noticed any in mine. and as for the emissions i just pay 60 cash no questions asked.