as the title suggests. im looking for suggestions and experiences with street mufflers in higher hp apps. my uncle has a 69 biscayne 427 car, but its got 600+ hp. its a pure street car. hes got some borlas on it now, dont know models off hand but i believe they are 3" in/out. but its too rappy and raspy for him. he wants something a bit more toned down when you hit it. doesnt mind if he loses a few hp but they have to be a quality muffler with lower dB. only ones ive used are flowmasters and i run delta force race mufflers and they are too loud. any suggestions?

 

Classic Tech might be the best place for this?

Rich

 

no mufflers are good lol, anyway, i like glasspacks, but they're loud, my dynomax always grabs a few cops' attentions

rappy and raspy is too small a tailpipe if i remember that right, call up any good high performance exhaust shop, i told my guy i wanted a good rumble tone, and he did the rest, but tailpipe size rill do a lot to a car's sound, smaller generally sharpens/'crispens'(sp) tone and larger makes it more long and broad like, like the lower you're searching for

but any muffler is going to cut off too much flow when you want power imho, so depending on his thoughts, you can go with a regular muffler, no fancy high flow mufflers or anything, and use exhaust cut outs (cheap like $30 each) to keep from losing your power completely.

but if you really want a good 'sleeper' they make silencers (i dont like them), and pointing your exhaust tips towards the pavement sometimes helps too, as far as a good muffler, dynomax, flowmaster, dynaflow... i'd call up flowmaster and tell them you want a sleeper that isnt going to lose much power in becoming a sleeper

 

if i were you magnaflow is the way to go...i have a 350+ hp TPI motor in my truck and it had a 40 flowmaster on it..way to loud for me so i put a BIG magnaflow muff on and it made a good diff in how loud it was...i would put 2 of the biggest muffs on that magnaflow makes it will give you a nice deep note and you wont loose any power because there is no baffels to stop flow like a flowmaster has.....

 

Does his car have a crossover tube, or balance tube? If not install one it will help the noise. Dynomax Superturbo muffs are the best and most quiet that I have found anywhere..tryem you'll like em.


Also you can put some bullet mufflers in front of the Borla's, will also help



David

 

i have you answer

all my friends back home with borla found a way to get rid of the popping, put a dynomax race bullet muffler before the borla's, it cleans up the sound a lot. they are like 36 bucks a piece so their cheap. they are racing strait through mufflers so he would lose no hp. get em through summit.

 

I'd try the bullets or even some twisters (spiralflows) in front of the borlas if you want it mellower.

 

My car made 570 rwhp with Jet hot long tubes, 3" off road pipe and a Hooker Aero chamber muffler. With the 3" electric cut out wide open the car gained one rwhp and lost four rwtq, that impressed me. With the stock SLP muffler I was blowing sound deadening material out of the muffler and plugging the air/fuel probe on every pull. The next day I put the Hooker Aero chamber on the car to finish the dyno tuning.

I am very pleased with the sound and performance.

 

Think what it would do with duals....

 

Probably gain a few more Hp, push my power band up higher and lose torque?
I would guess the power under the curve would suffer but peak numbers would look good.

 

flowmaster super 40's......

i am loosing my hearing but i love them on the 67'

i love all flowmasters.....

 

I had a 3" set up with two chambered flowmasters and dumps on my old 69 Camaro and later installed a header mount evac. system. The evac. system wouldnt work and acually caused more problems like oil burning, leaking, ect.
After changing the to a set of free flowing Borla mufflers the problems were gone and the evac. worked great.

 

in the old days we used to use Hemi mufflers. very quiet and worked pretty good
The best sound that I like are from Super Turbo's


Wade