(On the '57 - please forgive me. . .)
I intended to get them 2 years ago, but ordered their turbo mufflers by mistake. Decided to go with the turbos because I was running out of time before the race season started. Trial mounted them, sounded good, but the inlet went from 3" to 2" before any perferations! So, I got the die grinder & carbide burr out and did my own perferating - flowed okay, but really made them loud and crackily - I didn't like the sound at all, and had competitors in mufflers-required classes looking under the car in the pits (according to friends - I never witnessed this).

I finally decided to order a pair of their 3" fully welded mufflers last week when I ordered a Megashifter for the Camaro (save on the $9.75 per-order charge, you know). Arrived yesterday, but I didn't have a chance to do anything with them.

Tonight at the track, the car was making a really nasty rattling sound, which seemed to be coming from under the hood or under the car. After I went out in the 2nd round (and my son runnered-up in his class), I took the time to figure out what it was - turns out one of the turbo muffler outer cases has ripped open.

Talk about timing. . .

I'll install the new mufflers - no racing for me next weekend - and report on the results in 2 weeks.

 

i'm running these under my car in the 2.5" flavor...i like them alot...got a very flowmaster type of sound.

 

It's a pity the turbos were so restrictive-looking, because they sounded exactly the way I wanted. I suppose I should have run them to see how they really did, but I couldn't see how they could flow well at all.

Flowmaster type of sound, eh? Well, that's not exactly what I was looking for, but much better than what I've been putting up with. Getting home around midnight after a Friday night of racing was making me nervous about complaints from the neighbors - the perferated turbos actually were very close to the way-too-loud Bullets that they replaced. Flow-sound, I think I can tolerate, though.

 

A "Flowmaster kind of sound" will be a bit different behind that bigblock than the 10000000000000000 smallblocks running around with them.As you've said before,it's an aquired taste.Just like beer.Have I ever mentioned how much I love Flowmasters and beer?Guess I'm an adaptable guy!

 

The rips in the two case layers yesterday turned into a fist-sized hole behind the inlet tube end today. Like having a cut-out on one side. Almost improved the tone of the mufflers, but certainly caused anxious moments while running in a mufflers-required race. Made it through and home without incident, however (my ears were pretty rattled by the time I got home).

Having a Flow (single inlet, dual outlet) on the Camaro, I know what the "10000000000000000 smallblocks" thing is. However, not only bigblock, but duals - which Matt also has. Most Flows that I've been around are in single systems.

 

I know the two chambers in my car sound ENTIRELY different behind the 468 than they did behind any of the smallblocks I've had in the car.I'm running dual 3",with turndowns at the rear,which is a whole other sound in itself compared to tailpipes.

Guess I'm just "out of style",because I still love the sound of the chambered style mufflers.I also still think the original centerlines are some of the best looking wheels ever made,guess I just ain't hip.

 

Matt's 1990 Rally SportCoupe

click on that link and scroll all the way down to the video player. this what the mufflers/exhaust system sound like behind the old 9.5:1 c/r 305 with a 214/224 cam. now the motor has 10.4:1 c/r and a 238*/248* cam...you can imagine it's a bit more agressive than this.

 

I remember that clip. My system will be quite a bit different - 3" duals to 2-1/2" tailpipes, ~30" from collector to muffler, and as mentioned, BBC vs. SBC.

 

Well, got them in today. They sound just like the turbos did after I swiss-cheesed them (but not like they did after the side blew out of one).

We'll see next Friday what they do to performance.