[Sport69]

I have a 69 Firebird with a 350/4-speed. The heads are off a 71 with an Edelbrock Intake, 750 DP Holley, a mild-moderate cam (not sure of the exact lift/duration), and P.S., P.B,. In all of your experience what is best, headers or manifolds? There are manifolds on it now with a 2 1/2" Flowmaster set-up to the rear. Pretty loud as is, could stand to be a little quieter at normal cruising Send help Please!!!

[Sport69]

I have a 69 Firebird with a 350/4-speed. The heads are off a 71 with an Edelbrock Intake, 750 DP Holley, a mild-moderate cam (not sure of the exact lift/duration), and P.S., P.B,. In all of your experience what is best, headers or manifolds? There are manifolds on it now with a 2 1/2" Flowmaster set-up to the rear. Pretty loud as is, could stand to be a little quieter at normal cruising Send help Please!!!

[69f bird]

long branch manifolds...the best of both worlds!

Go fast while you're topless!

[Ccass]

Neither the high output manifolds nor Headers will make your car noticably louder. That's mostly a function of the Flowmaster 40's that come with that exhaust kit.

If you want the highest horsepower possible, get the headers. The long branch manifolds will be a close second but they will cost quite a bit more than a basic set of headers. However, the manifolds will last the life of the car. On average you pick up about 25hp with headers and about 15-20 with the Long branch manifolds.

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Fool around, Get hurt, don't come crying to me.

[bonneville Joe]

A good set of Headers will cost more than what a set of RePop LBs will run. Get the Long Branches. They will last forever. I don't think the car will get louder but you will probably notice more "Lope" or "Pulse" of the motor. The Log manifolds tend to mesh the exhaust sound together.



_____________________________
Foolproof and Sucka free since 1979.

[David Jones]

Get rid of the Flowmasters and get some Dynomax Turbo's or Super Turbo's. Your ears will thank you and the performance will be the same or better.

http://kurtspontiac.homestead.com/DavidJones69GTO.html

[bonneville Joe]

No way, keep the Flows. If its too loud you're too old.



_____________________________
Foolproof and Sucka free since 1979.

[David Jones]

It was a painful discovery for me, Joe. I AM to old.....

http://kurtspontiac.homestead.com/DavidJones69GTO.html

[Kybird]

I am not that old (40) and think that the delta flow 40's on my 67 bird are too loud. The 40's are flowmasters shortest street muffler and the only ones that will fit under the floor on the 1st gen birds. Also because of the rectangular shape, they hit on the factory traction bars as well. I plan to switch to Dynomax.

[Kybird]

As a follow-up, Dec 03 HiPo Pontiac has an article on headers vs. ram air style manifolds.

[Sport69]

Thanks to all for all of your help and advice.
Any particular brand of headers better for fit and durability than others?

[Kybird]

I used the Hooker Competition headers on my 67 bird Conv. They installed from under the car fairly easily, appear to be well made and are 16 gauge vs. 18 gauge compared to many others. They are also 1 5/8" vs 1 3/4 for some of the others (this should improve torque). They do hang down a little, I have to angle the car going of curbs.

[Tom Hand]

For your 350, look into the headers that PY sells. If they are out, look into Paul Spott's selection at Spott's Performance. They are also 1.625" diameter, average 29" tube length and have a nice long (9") collector.They fit well and with a bit of cleanup now and again in the center two ports, prove to be wonderfull headers. Go to www.classicalfirebird.com (I think) and look at their review.
Tom Hand

Tom Hand

[Sport69]

Tom,
Thanks for the info. Everything i've been reading tells me you're the man with the scoop on this subject. Thanks again.

Sport