Alternative side exhaust mufflers

[Mike R.]

My 65 FI roadster has side exhaust which (naturally) are loud(!!!). I also understand from another thread on this forum that the mufflers significantly reduce power due to their small innner diameter. Does anyone have experience with the "Vettepack" mufflers made by Classic Chambered Exhaust? They make both a 2.25" ID and a 2.5"ID muffler which, in additon to chambers, has a glasspack section.

I am hoping to make gains in power while reducing noise. I realize that these goals work against each other.

Thanks

Mike

[Roger P.]

Re: Alternative side exhaust mufflers

Mike:
I added my "2 cents" to a thread started on 11-10-09:

"I was considering something to make my sidepipes a little less loud to appease my wife, but I am going to hold off since I think they sound great (they're supposed to have a mean rumble). However, down the road, I might do something that "firstgear" did to his pipes that I read on the CF (you should be able to search the thread on the CF). As he explained and showed with a clear photo, he went to a local muffler shop and had them "custom make a couple of dual glass packed connected mufflers" (two mufflers connected by a small pipe on each side). They are bigger than the exhaust pipe, but still fit inside the sidepipe cover. He claims that they provide "an awesome low rumble, not a loud clanging or metallic sound". You might want to check it out as it could solve some of the HP and sound issues."

Mike, this sounds similar to the "Vettepack" mufflers, but might be more cost-effective. I don't know which is the better choice, but will consider the custom option and the Vettepack option when I'm ready to make the wife a little happier .

Roger (50141)

[Mike R.]

Re: Alternative side exhaust mufflers

Thanks Roger, I spoke to Classic Chambered Exhaust today and ordered thier 2.25" mufflers. I am hoping to be able to do a before and after dyno test along with a dB meter reading.

[Alan D.]

Re: Alternative side exhaust mufflers

Mike:
I added my "2 cents" to a thread started on 11-10-09:

"I was considering something to make my sidepipes a little less loud to appease my wife, but I am going to hold off since I think they sound great (they're supposed to have a mean rumble). However, down the road, I might do something that "firstgear" did to his pipes that I read on the CF (you should be able to search the thread on the CF). As he explained and showed with a clear photo, he went to a local muffler shop and had them "custom make a couple of dual glass packed connected mufflers" (two mufflers connected by a small pipe on each side). They are bigger than the exhaust pipe, but still fit inside the sidepipe cover. He claims that they provide "an awesome low rumble, not a loud clanging or metallic sound". You might want to check it out as it could solve some of the HP and sound issues."

Mike, this sounds similar to the "Vettepack" mufflers, but might be more cost-effective. I don't know which is the better choice, but will consider the custom option and the Vettepack option when I'm ready to make the wife a little happier .

Roger (50141)

Hi Roger
I have a 67 BBC with sidepipes. It is a very loud car. I would like to quieten it down somewhat. Did you ever do anything about quietening your car down and if so what did you do and how did it work? I also tried to look up the article from "firstgear" that you referred to but was unable to find it. I also live in Australia. so with shippping, import taxes etc. a set of exhausts end up costing about $1800 by the time they arrive here, so mistakes are costly. Any advice would be appreciated.
Regards

Alan

[Roger P.]

Re: Alternative side exhaust mufflers

Hi Alan,
I'm sorry for not getting back to you sooner. I haven't done anything with my exhaust yet since I don't find it too loud once driving on the road, and my wife doesn't join me for many cruises anyway . The post on the Corvette Forum is from a few years ago, but I assume it would still be archived. Even if you can't find it, I will try to explain what he did. He has sidepipes with standard chambered exhaust pipes which were too loud for his liking. He went to a muffler shop where they cut a large section out of the pipe that is hidden by the sidepipe covers. They then fabricated two "glass packed" mufflers (same shape as the exhaust pipe, but wider in diameter) connected together by a very short pipe and welded them back into the existing pipe. After the new mufflers, there was only a short piece of pipe and the chrome tip on the exhaust end since the mufflers consumed most of the area under the sidepipe cover. If you bend down low to peek under the car, you might see the bottom edge of the mufflers creeping out a little from the cover, but when standing, you can't see anything. Of course, this take place on each side of the car for a total of four muffers (2 per side). He claimed that the exhaust has a much quieter rumble, is much more enjoyable to drive, and it was much less expensive than purchasing a completely new system. There are aftermarket companies that claim to make quieter side exhaust for our Vettes, and you can even see/hear some "before & after" road tests on YouTube. However, I think it is worth giving the glass pack retrofit option a try since it sounds like a great idea and, if you don't like the result, you can always purchase one of the aftermarket systems (like Sweet Thunder, etc.). Please post what you decide to do, as well as your opinion of the result, so I can make a decision down the road based on your experience . If I find the link to the CF post, I will post it here for you.

Good luck,
Roger (50141)

[Joe C.]

Re: Alternative side exhaust mufflers

Here's an installation using Hedman sidepipe headers (to be ceramic coated winter 2010-11) into 3 1/2" x 2 1/2" Vettepacks using triple chromed steel tips.

[Mike M.]

Re: Alternative side exhaust mufflers

Hi Joe
I like the "Cut-outs", nice touch.
And you thought the side pipes were too loud???
What are your 1/4 Mile times?
HaND

[Joe C.]

Re: Alternative side exhaust mufflers

Hi Joe
I like the "Cut-outs", nice touch.
And you thought the side pipes were too loud???
What are your 1/4 Mile times?
HaND

Thanks for the compliment Mike.

I had the car to Raceway Park for the first time last week. It was HOT, with heat index over 100. Carb is set on the "lean" side, for now, and with the cut-outs closed, poor launch on the "bicycle tires" and careful, slow shifts, the trap speed was 107 MPH. Shift points were @ 7000 RPM.