I just got my 396 running a few weeks ago. When I initially got the engine running, I used cherry bombs bolted up right behind the headers. This gave a loud but resonance-free
sound. Last week I had 3 chamber flowmasters
installed with exhaust dumping right ovet the axels. Now the car sounds great but has
a "car shaking" vibration at certain engine
speeds. Is this normal for the flowmasters?
I am not sure if I can live with it.....
Other options?

Yep, that's the consenus on Flowmasters. Do a search on the subject, it's been discussed at length. I personally had a set of 2 chambers flows on a small block and went through the same thing, at around 2200-2500 RPM, it was quite annoying........KZ

Bob,

My Camaro SS396 has Flowmasters and I love them. They are the Delta Flow 50 Series. There is no resonance to speak of. They give my car a deep, mean sound. The add in Jeggs says that the Delta Flow series reduces exterior sound and interior resonance. My car is as loud as my dad's Nova that has 2 chamber Flowmasters but has none of the annoying "Flowmaster resonance". I recommend them highly.

My car: http://albums.photopoint.com/j/AlbumIndex?u=424666&a=3131121

DYNOMAX, I have had Flowmasters in the past, however the novelty has worn off. They do sound nice, but I would not want to live with them anymore. I recently acquired a couple of B-bodies that had Flowmasters, they will be coming off as soon as they become regularly driven.

Steve R.

I have a flowmaster full system behind hooker comps in my '68 ragtop 327. Mufflers are delta's, w/full tailpipes. While I've read a lot here about flowmaster resonance, my car has none of that!! Not sue if it's the delta mufflers, or maybe the h-pipe kills the resonance, but the car sounds sweet, in spite of the fact that my definition of sweet is a little different at 42 than it was 20 years ago.

The Delta Flow series was designed to eliminate the resonance problem. So if you don't want the resonance, go with the Delta series. Also, in speaking to a Flowmaster tech person, an "H" pipe will help with the resonance issue as well.

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Hugger Orange & white 69 Camaro with supercharged 350, Tremec TKO, and 3.73 12-bolt

See my website updated 9/01/00 at:

www.geocities.com/gheatly (http://www.geocities.com/gheatly)

I run a set of dual 3" 2 chamber Flowmasters and I can very well relate to the vibration problem. To make matters worse, I use 3" turndowns right after the mufflers. I can atest to the fact that adding an H-pipe did remove a bit (read not all) of the res and vibration.

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Mark
1992 Firebird 355/Six Speed
1991 RS 350 / 700-R4
1987 Toyota Pickup 383 / 500 + HP 10.963 @ 119.95
**How fast is just a matter of how much $$$ **
"They only thing worse than drinking out of the toilet is driving a FORD."
"FORD, the other F-word"

My Dad has a '69 small block car with the Flowmaster ful exhaust kit. Delta-flows and tail pipes. It has a horrible droan/resonance 2200-2500 RPM. ASt first, I thought it was a driveline vibration! It doesn't seem to bother him, but if it was my car, I'd pull the Flowmasters off!