Quite muffler that doesn't kill power...

[Grits & Gravy]

I need a 3" muffler for my daily driver that doesn't kill power... 550hp mild 496 BBC.

I have magnaflow ovals on it now but I want something quieter that won't hurt the power, how bad does something like the thrush "turbo muffler" hurt power?

[automotive breath]

I'm hearing good things about quick flow:

http://www.quickflowmufflers.com/products.htm

[bigjoe1]

We put the Magaflow longer ( 20 iinch) on an 820 HP car and it is soo quiet that it is embarrising. On the dyno, the 20 inch lost NO hP to the shorter 14 inch size.

JOE SHERMAN RACING ENGINES

[Grits & Gravy]

We put the Magaflow longer ( 20 iinch) on an 820 HP car and it is soo quiet that it is embarrising. On the dyno, the 20 inch lost NO hP to the shorter 14 inch size.

JOE SHERMAN RACING ENGINES

It is the 14inch that I have and I had considered switching too the longer version, you might have twisted my arm.

[VMC]

I tested a pair of Walker # 17665 3" mufflers on my own 530+ HP 496 on the dyno. With a pair of 3' long collector extensions (trying to simulate under-car pipes on the dyno) they actually picked up 30 ft.lbs and 32 HP over open 2" headers and no collector extensions, and were surprisingly quiet until you really leaned on them.

Eric

[hurstoldsracer]

Believe it or not, I had a set of the cheap Summit welded mufflers on my street/strip car 10 years ago that were very quiet. They were 3" offset/offset ran to the rear axle with no turn downs. It was an 85 Monte Carlo SS with a 14:1 421 SBC, and like Joe Sherman says, it was embarrassing it was so quiet. I switched to 3" center/center Flowmasters (the old style Outlaw mufflers) because I could not hear my car while I was going down the track. The car ran 7.000 (1/8 mile) before and after. The Flowmasters sounded good at the track, but were obnoxious on the street, drawing much unnecessary attention. I would go with the Summits again if I wanted a sleeper or something that did not give me a headache.
Mike

[CamKing]

We had a local stock car class mandate a certain muffler. On the dyno that muffler took over 20hp from the engine. I read the rules, and it didn't say how many mufflers, so I made a couple of 3" "Y"'s and ran 4 mufflers on it. It gained almost all it's power back, and it was the quitest car on the track. They quickly changed the rules to say "2 mufflers", shortly after they saw what we did.

[randy331]

I tested a pair of Walker # 17665 3" mufflers on my own 530+ HP 496 on the dyno. With a pair of 3' long collector extensions (trying to simulate under-car pipes on the dyno) they actually picked up 30 ft.lbs and 32 HP over open 2" headers and no collector extensions, and were surprisingly quiet until you really leaned on them.
Eric

It would be interesting to know how much power it would make with the 3' collector extensions, and no mufflers.

Randy

[randy331]

Camking, did the rules say unmodified? Could you remove some of the insides, or just run a pipe straight through the muffler? Then when tech looked under the car they would still see mufflers.

Randy

[bigjoe1]

I have tested the mufflers against collector extentions befor and they work exactly the same ( Magnaflows)One car I know runs a tiny bit FASTER with the mufflers than without ( even though the weiigh 45 pounds)Once, on an 800 HP smallblock, adding the mufflers PICKED UP 8 or 9 HP at the peak.

JOE SHERMAN RACING ENGINES

[torquefan]

I have tested the mufflers against collector extentions befor and they work exactly the same ( Magnaflows)One car I know runs a tiny bit FASTER with the mufflers than without ( even though the weiigh 45 pounds)Once, on an 800 HP smallblock, adding the mufflers PICKED UP 8 or 9 HP at the peak.

JOE SHERMAN RACING ENGINES

big joe, any thoughts as to why that happened? does the muffler make the engine think it has a smaller exhaust port?

[FASTFATBOY]

Dynatech splitflow muffs are quiet, Never seen a test on them. But there are a few cars around here going quick with them.

DAvid

[randy331]

Would gaining power when a muffler is added, suggest a different header is needed??
Does the muffler dampen, eliminate, or change the timming, of an exhaust pulse that was out of time with the engine??


Randy

[CamKing]

Camking, did the rules say unmodified? Could you remove some of the insides, or just run a pipe straight through the muffler? Then when tech looked under the car they would still see mufflers.

Randy

You can't touch them, and they have to pass a Db test.
We just went to the biggest tube we could after the collector, and ran it all the way to the back of the car, and then stepped it down for the muffler.

[CamKing]

Would gaining power when a muffler is added, suggest a different header is needed??
Does the muffler dampen, eliminate, or change the timming, of an exhaust pulse that was out of time with the engine??


Randy

If you gain power by adding a muffler, your engine was inefficient to begin with. Any power gain you see by adding a muffler, was just part of the power that was lost by something else being wrong.