[Sporter]

Can't quite find the room to run tailpipes on Dynomax 17749 mufflers on my 67 Firebird. Question is which would be quieter, the long case (20") 17749s with turndowns or the short case (14") 17734s and tailpipes?

Rest of the system is 3" pipes, 3" x-pipe, 3" electric cutouts, 3" to 2.5" reducers just before the mufflers.

Thanks.

[Ollie]

Originally Posted by Sporter

Can't quite find the room to run tailpipes on Dynomax 17749 mufflers on my 67 Firebird. Question is which would be quieter, the long case (20") 17749s with turndowns or the short case (14") 17734s and tailpipes?

Rest of the system is 3" pipes, 3" x-pipe, 3" electric cutouts, 3" to 2.5" reducers just before the mufflers.

Thanks.

I would run the 14" 17749 and tailpipes. Gets the noise out from under the car.

[briann]

Originally Posted by Ollie

I would run the 14" 17749 and tailpipes. Gets the noise out from under the car.

And its not so much the noise but with my turn downs I create a huge dirt storm behind me no matter if I'm stopped or moving. I'm like a 500 hp leaf blower.

[bonneville Joe]

I would run tails, if you run turndowns when the car is sitting at idle say at a red light you will get the fumes rolling out from under the car and up into the open door windows. Not a fun situation. Its much better and safer to have the fumes escape safely out of the back of the car.

[Colin Frolick]

turndowns are LOUD. my car with a fresh 455 and turndowns gave me a headache.

what about side pipes heh?

[Sporter]

I'm going with the 17734s and tailpipes. If its too loud I'm thinking of adding an ultra-flow transverse muffler to the 17734s, like the factory arrangement. Should be very quiet then.

[Tom Hand]

Sporter, be careful that the Ultraflow transverse muffler, like many others, is straight through and if you connect both side to the same top or bottom inlet, you will not be able to get much exhaust out of it. In other words, you need to modify the pipes like we did with the crossflow PY sells. If you plan to use one, that would be the one to use and mainly because of the reversed orientation pipes.
Tom

[Tom Hand]

Sporter, be careful that the Ultraflow transverse muffler, like many others, is straight through and if you connect both sides to the same top or bottom inlet, you will not be able to get much exhaust out of it. In other words, you need to modify the pipes like we did with the crossflow PY sells. If you plan to use one, that would be the one to use and mainly because of the reversed orientation pipes.
Tom