I am building a 461 for my 70 cutlass, aluminum heads, mondello 25-28 cam, 455/.030 and was wondering first if any one has used this cam, is it extremley lopey, and if anyone has used cherry bomb extreme mufflers and if so are they happy with them. they are one chamber.

 

Muffler Choice: Something to consider is the vibration or resonation you get from the sound/pitch at different rpm in your particular car. I've found over the years, especially w/ performance mufflers, that along w/ the sound you want comes an unwanted vibration or resonation at different RPMs that's a total drag and actually vibrates parts of your vehicle. I know that Flowmaster has reviews of the different muffler series that they manufacture. Try looking up the reviews by the MFG of the muffler you're considering. Good Luck.

 

From what you posted, it seems that 3" exhaust would be warranted. I suggest straight pipe after the headers (or Pypes/torque tech head pipes with manifolds), then Walker 21468 mufflers, then Torque Tech or some such mandrel bent tail pipes.

 

I imagine you're going to run headers with that motor.. take a look at the Torque Tech X-pipe setup, it will quiet it down a little. I run a 2 1/2" system with Spin Tech Pro Street's and it sounds good

 

James455, Is this car going to be something that you don't drive all the time, maybe only from time to time on the street? If it's something you'll drive regularly on the street, I'd go w/ a 2 1/2" stainless system and performance mufflers of your choice. W/ headers, install a cross pipe about 18" back from the collectors so you still have some bottom end. If there's a shop around that does good exhaust work, you can have a good system installed and not pay a crazy price f/ a brand name complete system. I've found that the pipe connections look nice when a torch is used f/ a nice evenly flowing bead over the joints. If you're going w/ a super radical system, then you won't have much there anyway.

 

I was thinking the same thing.

I had headers, 2 1/2 inch exhaust and two chamber flowmasters on my 69 350. Very noisy with a lot of resonance.

I imagine that the setup your talking about would be just as bad with the cherry bombs. If you don't want something with a lot of resonance then I would go to Walker's or three chamber flowmasters. Would still sound aggressive but it would cut down on the unwanted vibration.

 

Do you have a video of your car running/idling?

 

No video, but I'll work on it, here is the link for Spin Tech,
http://www.spintechmufflers.com/
And here a couple pics of my system

 

I reccomend 2.5 inch with Dynomax super turbos. It's a little raspy but not too bad. I let off the gas when I hit 4th because it was the first run down the track for the car.
http://www.youtube.com/watch?v=jwgcyYxnqHI

 

I have 2 1/2" stainless pipes w/ 40 series Flowmasters coming off the headers on my 'Vette and it's not that loud, and w/ the snuggly mounted rubber hangers, I get no resonance, something I was worried about. It not being terribly noisy may have to do w/ the routing as the mufflers on the 'Vettes are all the way to the rear and the pipes take two hard turns, out then in, after going under the differential to connect to the mufflers. I had the system put on in Shreveport, La. by a guy who does all the custom exhausts in the area and was recommended by a high dollar rod shop that had several of their builds in a number of car magazines. The exhaust guy did all the work himself, was very straight foreward and showed you everything he was doing as he did it and why. He's also an artist w/ the torch. And unlike the rod shop, he was very reasonable w/ the price. He rubber mounted all the hangers. W/ the spare tire cover removed, the exhaust system on my 'Vette looks fantastic from the rear, really something to be admired. When I finish my '62 pick-up w/ the 455, I'm going back to that same guy f/ the exhaust. It's worth every bit of the 325 mile trip to have that kind of quality. In the past and over the years, I was forced afew times to buy aftermarket systems and installing them myself due to not knowing anyone who did really good exhaust work, as good custom exhaust shops are hard to find.

 

The mandrel bent systems made by Torque Tech,Pypes and a few others are very well made and quality and fitment is topnotch. I'll take mandrel bent over muffler shop stuff any day.

 

Texas Jim,

Do you have pictures of your exhaust system? What do the rubber mounted hangers look like?

 

If you're referring to Midas Muffler or some trash like that, I agree, but there ARE a handful of knowledgable exhaust guys out there. That's like saying you'll go w/ a crate engine instead of a pro machine shop build. W/ a good exhaust guy, you can get "exactly" what you want and what works f/ "exactly" what you have. I will admit, there just aren't many out there, probably due to the fact that there isn't alot of money in it.

No pics on the computer, but I'll load some up.

 

I bought a Pypes kit and its not installed yet but it sure looks good. Yet to hear any bad words about them.
That being said I work near Stans Headers and Mufflers who is nationally known for high quality work. While its been a number of years since I've been inside his shop the few times I did it was amazing ! Mandrel bent no problem for a "custom" exhaust shop. http://www.stans-headers.com/about.htm

Just food for thought.

 

Let's face it, the brand name performance exhaust systems that are sold as a unit, or parts of a unit, are engineered to work, and no doubt perform well. I personally know first hand that f/ afew different year Corvettes there are good aftermarket exhaust systems that flow super well and fit like a glove, perfectly through the center of the frame cut-out(s) (both sides on the C2 and one side on the C3), etc.. They also sound great w/ little resonance or vibration. I'm only saying that at a shop that stocks the quality materials, cuts, bends and installs a system to fit properly, and where the fabricator/installer knows how to engineer a good system f/ the performance level you need and/or want, it's the best of both worlds. You get the system you need/want, and have a competant person to install it right the first time, and DONE. I personally like the looks of a nicely flowing bead from a torch at the joints (ie; pipe to muffler). It's a butted and flush fit w/ no flaring involved. Like w/ anything, this is only my personal opinion. Others ie may feel differently and swear by a certain brand name and enjoy installing the system themselves. I say, to each his own.

nonhog, Stan's looks like a neat place. Nothing like touring a fab shop of sorts or watching work being done at a place like that. I had reversed eye main leafs made f/ my '62 Ford p/u about 20 or so years ago at "Waco Spring and Brake" where they make any kind of spring and fit them to your vehicle, or whatever. I got talking to the manager who had an old International Scout sitting ourside that he drove to work each day. He took me through the shop where they've been located since 1923. The manager had the least amount of time in there and had been there f/ 25 years. They were, at that time, looking f/ someone to start training on the many machines, as this old guy was retiring in afew months and had been there f/ over 50 years. The manager said that this guy was the master, could make anything and had done it all. I watched the guy work f/ about 10 minutes and could have stood there and watched all day. Everyone else there had been doing the work f/ 30 plus years or more. What a shop! Needless to say, the main leafs I had made fit perfectly and the manager gave me afew strips of teflon to put between the leafs to stop any binding, and they stocked any bushing size you could think of. I think places like that alot of times get phased out by the big distributors who have stuff made overseas cheaper. Screw that! I'll go to a "pro-type" specialty shop anytime.