ssanto
New Reader
6/12/22 6:57 p.m.
I've got a 350 SBC in a road race car that runs up to 6800 RPM. I figure it's about 500 horsepower.
I'm trying to get the car to be quiet (for various reasons). Right now, I've got 1 3/4 long tube Schoenfeld headers with 4 inch collectors. And then right off the headers I've got a set of 2 1/2 inch Dynomax Super Turbo mufflers. And then 2 1/2 inch pipes out the side of the car. They are quiet enough. And it's hard to tell if the car is really down on power after putting on those mufflers. However, I'm considering switching to a set of the 3 inch super turbo mufflers (and then 3 inch pipes out the side).
2 1/2 inch muffler body dimensions - 4 1/4 x 9 3/4 x 14 inches
3 inch muffler body dimensions - 5 1/2 x 11 x 16 inches
As I understand it, the 3 inch muffler should flow more. And as I also understand it, bigger sized mufflers quiet the car down more. So do you think changing to the 3 inch mufflers would give me better flow AND quieter sound? It seems a little too good to be true ;)
Thanks!
Engine masters did a test on this, but sound wasn't part of it. You are right on the edge of "benifiting" from 3" exhaust. I'd try it.
Yes, bigger mufflers are generally quieter (within the same family - Super Turbo to Super Turbo), but the 3" pipes will tend to make the system louder. I think the answer is "We don't know", but my guess is that the difference will be minimal.
A cross-over would reduce noise. And two 2.25" pipes per side, after the muffler would probably reduce noise and also provide a small amount of extra ground clearance.
ssanto
New Reader
6/12/22 8:51 p.m.
I can't get a crossover in before the mufflers. After I could do it.
I've been pondering taking the car to a chassis dyno. I'm curious about what power the motor makes. And also I'd like the opportunity to dial in the timing and jetting. It's hard to juggle changes like that on the track days with everything else going on. I could do a final pull with the mufflers off and see how much they are costing me. That might give me some idea of what going to a better flowing muffler might buy me.
