OutLaw305

I am placing the order on a crate 350 from Performance Engine Rebuilders which i should get to install mid summer on my car. The numbers it puts out are 360hp and 385trq. With that being said:

1) what size headers hsould i get (im going shorties for sure)
so...get 1 3/4 or 1 5/8??
2)I went up to the speed shop that im going to get the work on my car done, and when asking him about a dual exhaust set up, he mentioned that he swears a 3" y-pipe will perform just as well as a dual pipe set up and leave more room. I have always been under the influence that duals were far superior. Was i wrong here or is he just filling me full of crap?

five7kid

iTrader: (14)

1-5/8" shorties, no less than 2-1/2" down-pipes, no less than 3" after they join will support around 400 hp.

You'll be fine with Hooker 2055's & similar cat & cat-back.

iceman02

iTrader: (1)

Yea, yea, yea, but duals are more cooler!

five7kid

iTrader: (14)

Especially when they hang 6" below the lowest body part.

MrDude_1

the ONLY long tube setups that are cool are the ones where they took the time to mod the "frame rails" or crossmember to allow ground clearance to remain unchanged.

even then its not a bad idea to have it go into a Y pipe.

my exhaust will consist of longtubes, dual cutouts just after that, then by way of a modded crossmember, out to the quietest catback i can get.

when i want to be loud, i'll have the dual cutouts... but when i want to talk to the person next to me, not attract attention from the cops, not **** off my neighbors at 3am and floor it on the street without people looking at me, i can keep them closed



anyhoo, my fav longtube setup that ive seen on here.. i forget whos it is, someone remind me:

MrDude_1

one more to show it better.

note the crossmember.

five7kid

iTrader: (14)

Dude, you're talking long tubes, the topic was duals.

MrDude_1

i know.


longtube = duals. you could easily ditch the Y from what i posted and put dual pipes going back.


running shorties as duals is just plain stupid
(only "advantage" is the sound)

Marc 85Z28

iTrader: (3)

Care to elaborate? And I'll advise to tread carefully, as I have TONS of evidence to the contrary of your statement

MrDude_1

sure.

if you're running shorties, you arnt after max power anyway.

so why expend the extra effort for duals when the gain you see may only be slightly visible at the strip?

dual cat cars are already halfway there, they just need to continue back, but a decient aftermarket Y pipe will support any motor that should have shorties on it.

after around 400hp or so (about the same area five7kid said) you should start considering longtubes anyway.


so really theres no point unless you either have a killer motor with shorty headers, or you just want the sound.
and if you have the motor, you should just put longtubes on it now..
btw, im not saying bigger primary tubes are better, get whats right for the motor, but longtubes do outflow shorties.

OutLaw305

how much of a difference will i see going ot the longtubes though? I will be for sure keeping te Y-pipe now, never thought of putting the cut outs before the y = duals when open. I just am worried about clearance issues. Thats the only reason im thinking of gettin the shorties. If my engine makes 365 hp and 385 trq, how much will i be restricting myself with putting shortys on as opposed to long tubes?

five7kid

iTrader: (14)

For the engine you're considering, shorties with 3" single pipe will be fine.

If you were going for the nth little bit of advantage in say a stock class drag racer, you'd be going with longtubes (and no exhaust after that). But, you wouldn't be installing a 350, most likely, and you wouldn't be seeking advice from a board like this (nor telling what you did on a board like this).

Marc 85Z28

iTrader: (3)

MrDude_1: I've got a Car Craft mag (I know, I know) right here detailing the difference between shorties and full length headers. Given the same primary diameter and collector design and size, the shorties often make MORE power than the full lengths. The full lengths will make more torque however. This was proven on a fairly stout (well over 400HP) SBC. GMHTP or CHP did a nearly identical article with the same results.

After you catch that article, I'll go into depth on a 10.80 91Z28 that went 3mph faster with SLPs shorties than the Hooker Super Comp LT's.

IROCZZ3

That's interesting to know, the LT1 guys claim they went faster with LTs over shorties.

FWIW, I'm running SLP 1 3/4 shorties and I'm debating if I should switch to LT's. Now I'm not sure if it will be worth it......

MrDude_1

heres a intresting parodox for you.

there are 1000s of engines dynoed that made more power with a large carb spacer.. there are also 1000s dynoed that lost power with the same size spacer..


i suppose its because..... things like that are entirely dependant upon the engine.



for the engine hes talking about, shorties would be fine.
but i wouldnt run a dual exhaust with it.

OutLaw305

thanks for the input guys