451 exhaust size

[dart6]

Would 2 1/2in exhaust pipe be big enough [I already have mufflers] Or would i be better off going with 3in
thx

 

[RustyRatRod]

2.5 is plenty big.

 

[MikeyT]

What is the purpose of the build? Also, can you tell us how radical the 451 is that you built?

I agree with Rusty for the most part, unless it is a racer.

Mike

 

[68GTX4SPEED]

I was told that 2.5" is enough for 500-550 hp.

 

[Darter6]

I ran 2 1/2 on my 65 belvedere to the back bumper.451, 3500 converter, 4.10's.
Schumacher tri-y's.11.96@110 mph 3600 lbs.Full street trim with drag radials.
Worked for me.A friend bought a 67 R/T and it came with 3'' on it . After growing tired of messing with clearance issues he replaced the entire system with 2 1/2 and the car actually ran better. Just a thought..

 

[dart6]

it's about 500hp with eddie heads 10.5 cr hydraulic roller about 540 lift, auto street driven 70 sport sat

 

[RustyRatRod]

You'll be fine at 2.5". BUT I will say this. I don't know what it is. But when you go from 2.5 to 3", the sounds gets a LOT better. I've made the change on several cars.....that probably didn't need 3" and without fail they all got louder and the sound quality increased dramatically.

 

[dart6]

ok thx for that

 

[MikeyT]

2.5 should work fine for it.

Mike

 

[Brads70]

I've got the 2 1/2" stainless magnaflow kit and headers on my 451" , works great!