Opinions wanted until exhausted!

[78SilvAnniv]

All suggestions considered!
I want to change my CA exhaust this year. Has a standard single exhaust system and I wish to change it to dual. I will be saving everything taken off in case we ever move back to CA.
I would like to use headers, to make for easier at-home plug changes, and need recommendations for good sounding mufflers to use. I'd like a 'healthy, deeper tone' but would not like excessive noise while driving.
How much would removing the catalytic converter, smog pump and putting on headers with dual exhaust increase my horsepower and mileage? I currently get about 18mpg average out of a tank (supreme only). L48 @ 185hp stock.
I had a Camaro in college with headers and had oodles of trouble with exhaust leaks from the gaskets. Have today's gaskets improved? Is there something that I should do at this time that I have not mentioned? Please share your opinion, pros and cons for what I have planned.

(*found engine to not be original when it went to the rebuild-shop-in-the-sky so in '97 I put in a new GM long block)
I'll also be replacing the entire ps system and upgrading to a high performance water pump for this daily driver.

Silver

 

[ssvett]

78Silvanniv, You asked the most important question about three quarters through, "Have todays gasket improved?" It has been my experiance, and my experience with headers is pretty extensive, my answer would be, maybe, but I would also have to say that the headers, and the materials that they are made of has not. One thing you need to remember is, that headers are designed for one thing, no matter what the manufacture says, and that is racing.... Headers, as we know them in the aftermarket world, remain to be the bothersom free flowing exhaust leaks as they ever were. Now about your original "rams horn" exhaust manifolds. These are the manifolds of choice for the local dirt burners (local stock car racers, bomber division) who by sanctioning rules are forbiddin to run headers , are always looking for. As far as manifolds go, I would be very surprised to find that any other small block manifolds flow as well, with almost no failures as do these manifolds. (however, if you insist on headers, by the way they won't make changeing plugs much easier, spend the extra money, and get the ceramic coated ones.) Ok, exhaust, on the ole '74 I have, and this same exhaust will fit your '79(for off road use only, of course)2.5 inch aluminized with 2 chambered Flowmasters. They made the ole '74 sound like a hot rod.(BTW I can get you a good deal on the exhaust pipes, check out the parts page on the home page address below) I hope this helps. I have installed this system on many Corvettes from '69 to '81(for off road use only,of course) The HP gain in my opinion, will be minimal by intalling headers when compared to the cost and eventual headaches. However, I do think headers are cool and they give a car a special sound. The final decision is yours. But I felt that I should give you my experiances........Hope this helps in your decision makeing.....Steve

 

[78SilvAnniv]

thanks for the advice!

I thought headers would give more access to the plugs, if not...perhaps I'll just use the existing exhaust manifold.
My thought on easier access with the headers stems from a bad garage charging me for installing 8 splitfire plugs, and when the engine blew my new, trustworthy/reliable (family member-in-law) mechanic showed me 5 splitfire plugs and 3 old ones that he took out of the block. Needless to say, I took the bag of plugs back to them and asked them how they were going to make me happy!
I would have much preferred to pay and wait extra to have the job done right instead of being defrauded.
Thanks for such an informed reply.
Silver

 

[Stingray6974]

Hi Silver,
SSVette made some good points about headers. I have yet to install a set without having to do a little welding and grinding in the flange area. Changing the plugs isn't any easier, just different. For a reliable no - maintainence exhaust stick with the manifolds. I'm putting headers and sidepipes on my '69, but using the stock system on the 74,
( steve I may be calling you ). Headers on a stock motor are worth about 20 hp at best and definitely not worth the hassle.
Mike

 

[ssvett]

All calls are welcome.........Thanks...Steve PS Sam(ssvettJR) Still needs more pictures for his year by year page on our web sight.......Please click below.....

 

[Yoda]

Steve & Sam Nice Website

Steve,

Wow, your website is updated all the time, and looking really good. How do you guys find the time to do all that? I really like the driveway full of Corvettes

Thanks for sharing your knowledge and putting our link on your website too

BudD

 

[Tom Bryant]

headers

Silver, Steves is right. If you have a stock or mildly built street only engine you will not gain much that you can feel by using headers over rams horn manifolds and a good free flowing duals system. I'm using rams horns and a chambered exhaust on a mild 350 (Offy intake, small Holley. Goodwrench/Crane street cam) in my '69 stepside C/10 just so I don't have to hassle with leaks. Also iron manifolds basically last forever. Maybe I need to hire a temp to keep up with Steve in developing my web sight. Haven't touched it in a couple weeks.

 

[78SilvAnniv]

thanks to all

Thank you all for your replies, I have decided to keep the exhaust manifolds and not use headers. I would still like opinions on mufflers and which ones would sound best.
ssvett-I'll check out your site for the pipes. Thank you.
Silver