Would 3'' exhaust with H pipe be to big ?

[madmike9396]

I have a 440 in my 68 plymouth Sport Satellite and im thinking of going with a 3'' exhaust with H pipe and Magna Flow Mufflers, They will stop at the axels, it has the good manifolds,

Thanks to anyone with info

 

[daredevil]

you say it has the good manifolds. no headers?

 

[madmike9396]

No it does not have headers/ i forget which manifolds it has but i was told they were like factory headers but there manifolds.

 

[madmike9396]

bump^^^

 

[69HEMICORONETR/TCONV]

I think 3 inch exhaust is Extreme Overkill for stock exhaust manifolds.

 

[A383Wing]

Bigger ain't always better..kinda like carbs...too large a carburetor will actually make less power

Too large of exhaust will not scavenge the cylinders properly, thus sometimes leading to less performance and horsepower loss.

2-1/4" to 2-1/2" would be the largest I would go with a stock engine

 

[madmike9396]

well it has a medium cam so 2 1/2 would be the largest ? Ive seen camaros run 3'' exhust with 383s that why i figured it wouldnt bother a 440 with 3'' exhaust. it has 2 1/2 now but its rusted up thats why i was asking because i ve gotta get new

 

[69HEMICORONETR/TCONV]

just like A383Wing said, "Bigger ain't always better.."...........and I have blowed the doors off of several Mustangs and Camaros with big bad 3 inch pipes...........with Hemi's and 440s with 2 1/2 exhaust.


A good example is I had a new Harley, brand new, bone stock, with mufflers,......I put straight pipes on and lost ALL my bottom end torque, .....the bike was actually slower with the pipes than through the mufflers.

 

[madmike9396]

yeah i know to big is bad but i didnt know if 3'' was to big or not but from the answers im getting 2 1/2 will be plenty im assuming

 

[dantrap]

Check out the attached link, there are formulas for exhaust design. The charts are for both big and small block mopars.
http://victorylibrary.com/mopar/header-tech-c.htm

 

[69HEMICORONETR/TCONV]

Check out the attached link, there are formulas for exhaust design. The charts are for both big and small block mopars.
http://victorylibrary.com/mopar/header-tech-c.htm

Good Info ! :yes:

 

[madmike9396]

thanks guys what type of exhaust are you running ?

 

[69HEMICORONETR/TCONV]

thanks guys what type of exhaust are you running ?

2 1/2 with H pipe.

 

[dantrap]

Modified hooker headers, custom bent 3"dia. that stops before the rear axle no x-pipe. The Leafs are moved in so i had no room to run them all the way back. I am adding electric cutouts when the it warms up around here. For your mild 440 a good 2 1/2" dia system all the way back and a set of 1 7/8" dia headers would work fine. You could always add electric cutouts if you go to the track. good luck.

 

[A383Wing]

thanks guys what type of exhaust are you running ?

I'm running 2-1/4" on the black 66 and the Daytona...the cream 66 still retains it's stock exhaust system from the factory

 

[madmike9396]

thanks for the info guys

 

[Gary_gtx67]

1967 gtx clone with a hoped up 383 headman headers with a complete 2 1/2 with X pipe not H pipe to 2 flowmaster 10' series. I personally hate the H pipe. The X pipe will flow mch better and you can buy the kit from summit for $100 BUCKS!!!

 

[69HEMICORONETR/TCONV]

H - pipe

Advantage - cheaper (and personally I think they sound better).Deeper, Rumbling tone, a little more torque, uses less space, also used by the factory,

Disadvantage - slightly less HP

X-pipe

Advantage - It's worth a couple extra High end hp over an H. more scavenging.

Disadvantage - a little more expensive, needs more room,higher pitched sound,slightly less torque

 

[Gary_gtx67]

Give me proof that a h pipe produces more power and torque than an x pipe? Every dyno I have seen the x pipe produces more power and torque any day!

 

[69HEMICORONETR/TCONV]

Give me proof that a h pipe produces more power and torque than an x pipe? Every dyno I have seen the x pipe produces more power and torque any day!

Re-read it,.... s l o w l y...., I said the X a slight HP advantage.:head_smack: I never said it makes more Hp and torque.


There is a distinct difference in Horsepower and Torque.