tips for bring the best exhaust tune outta me 350 (76 vette)

[aussie_stingray]

i have a '76 vetter... and has the 350 yadda yadda.. i am currently buying a set of hedman hugger headers... and i want to get that sweet purr of the exhaust tune that chevs are so famous for .. any setup's anyone recommends? since i have a twin system.. im thinking as the headers are 1-5/8 to a 2- 1/2 inch collector.. ill do 2.5 all the way to the mufflers.. maybe have them gutted??? and chrome tips?? or would that be too loud... oh no im confused hehe

 

[Eric]

I have three possible suggestions for you - 1. chambered exhaust, 2. chambered exhaust, and 3. chambered exhaust. I am a bit partial since I have the system on mine but I get nothing but compliments on it. An added benefit is that there are no unsightly mufflers hanging under the valance panel - bonus!

It is a little loud at full throttle though but I still love it.

-Eric

 

[78SilvAnniv]

Chambered

This is what I am planning on doing to mine, after other driveability safety issues are first met.
Silver

 

[mmvette80]

Are the chambered mufflers emission legal in all states?

 

[Bob Chadwick]

What is the difference between a chambered exhaust and a Flowmaster, or is the Flowmaster a chambered exhaust?

 

[Dave L.]

Flowmaster is a muffler.It is actually a brand name.Chambered exhast is a pipe with baffles init that serve as a muffler,so to speak.

Dave

 

[Eric]

Are the chambered mufflers emission legal in all states?

Yes and no. I've never seen a chambered system built for a shark with a cat, only C4 and C5 owners have that option, so if you have a cat you probably can't go with chambered unless you are emissions exempt. Even then you should check local laws regarding cat removal. If your car was from the pre-cat years, no problem, the adds for chambered systems claim they are 50 state street legal. Since mine is a 71 the only emissions equipment is a evap canister so it was no prob for me.

Burglar's statement about chambered is right, the chambered system passes as a muffler so that's how it ends up being legal.

-Eric

 

[Bob Chadwick]

Eric,

I don't even think they are local laws. I think the feds mandate that if the car came with emissions equipment, including cats, legally they have to be left on. This is irrespective of the various state laws on emissions testing.

My 77 does not require emissions testing in Georgia, but the smog stuff is still supposed to be on it, even if it doesn't work.

Could I remove them and never get caught? Yes unless the testing laws change here, something that would not surprise me considering how bad the air is in Atlanta metro and it keeps getting worse.

I weighed all the options, and decided to put a true duals with 2 cats on the car.

Bob

 

[Eric]

Eric,

I don't even think they are local laws. I think the feds mandate that if the car came with emissions equipment, including cats, legally they have to be left on. This is irrespective of the various state laws on emissions testing....
Bob

I'm sure you're right about that. Honestly, that's one of the reasons (along with a love of chrome) that I went with one as old as I did. On the flipside many states (mine included) have rolling exemptions. Another thing we have here in Va is our vintage plates which, believe it or not, exempt you from any inspection whatsoever including the annual safety inspection. Now of course there are numerous restriction on when/where you can drive the car but some are willing to live with it just to have a way to build the car they want. I personally have normal plates and get my 31 year old car inspected every year for peace-of-mind.

As for removing the equipment, I wouldn't do it to my own car if it had it but to each his own. When the day comes that I end up with a Vette with cats all of my exhaust work will be cat back.

- Eric

 

[Bob Chadwick]

Eric,

My plan is to put on a 2 1/4 inch true dual system, Flowmaster recommended a slightly smaller pipe due to the low HP of this model year, with dual cats and flowmaster mufflers.

Please explain what a cat back system is and the pros and cons with what I am proposing.

Thanks.

Bob

 

[Eric]

Eric,

My plan is to put on a 2 1/4 inch true dual system, Flowmaster recommended a slightly smaller pipe due to the low HP of this model year, with dual cats and flowmaster mufflers.

Please explain what a cat back system is and the pros and cons with what I am proposing.

Thanks.
Bob

Sorry Bob, my cat-back comment was more intended for my next Vette which will be a C4 most likely - my apologies for straying. A cat-back system is one built to replace everything behind the cat. What you get is the kit-and-caboodle - pipes, mufflers, and often custom tips as well. Most of the manufacturers of the really nice cat-back systems (Borla, Corsa, etc..) have turned their back on older cars for financial reasons most likely since there are a lot more C4s and F-bodies and C5s running around looking for more power. These systems use lower restriction mufflers, larger pipes (usually), and some even add the ability to tune your exhaust on the fly.

Your route, in all honesty, is probalby one of the best solutions one could ask for while staying within legal bounds. Most would not foot the bill for a dual cat system but it makes perfect sense if the price is right. The reason Flowmaster recommended you stay with the smaller pipes is most likely to maintain appropriate back-pressure in the system - something often thrown out the window. Heck, the only thing missing is a crossover pipe to assist in flow. It sounds like you will have a nice system when complete.

- Eric

 

[Bob Chadwick]

Thanks for the advise Eric. The back pressure is the reason for the smaller pipe. I am getting the cross over pipe as well.

Bob