z28-50

iTrader: (2)

How much difference in performance difference or where the power band is between th 1-3/4 or the 1-3/4, 1-7/8 stepped headers is their.

95 LT1 M6 with most all boltons, but no headers, hypertune tuner.
Free mods as well.

BOLO

iTrader: (40)

It all depends on whats done to the motor. 1.75" is more than adequate for a typical heads/cam combo. The latter maybe needed for the larger stroker build.

pancho toco loco

iTrader: (8)

1At your power level 1-3/4 will be just fine. Think you need upwards of 500hp to nned the larger 1-7/8. ( dont quote me on that one) The stepped headers scavenge better than a straight tube header and broaden the torque curve.

96capricemgr

iTrader: (1)

At your level and for heads/cam cars 1 5/8" is fine, the bigger tube will just make plug changes worse.

ABA383

iTrader: (1)

As much of a pain as it is to install headers on these cars I'd go with the stepped series 1 3/4- 1 7/8s...I ran them on my old formula and while we are at different power levels the initial 1 3/4 primaries help scavenge and keep velocity up which keeps low end torque from being drastically effected. If you decide to step up your power down the road your headers will already support it.

--Alan

96capricemgr

iTrader: (1)

Can anyone sight an example of even 1 3/4" being a genuine upgrade on a heads cam car vs. 1 5/8"

I know of a 10 second car that went from 1 5/8" tri-Ys to 1 3/4" longtubes with little to no effect.

I have run 1 5/8" midlength, 1 5/8" tri-y and 1 3/4" longtube on my car and saw no appreciable difference other than plug changes are terrible with the 1 3/4" headers I bought.

BizZzatch350

iTrader: (33)

I have the Kooks stepped, plug changes are no worse then the Hookers I had before, maybe even easier. A lot better than a car with stock manifolds. Only thing that's worse is getting to the starter bolts is kind of a pain.

WS Sick

On headers I would pay more attention to the collector size and the merge than primaries diameter and length. Sure at some levels the larger primary size will be a benefit, but not on a heads and cam car IMHO. 1 3/4 will do just fine.

ABA383

iTrader: (1)

I can only give an example of going from 1 5/8" to the stepped Kooks on my set up, which I know is not just a h/c car, but my heads were nothing special and the cam was weenie by most standards with similar specs to folks who run h/c cars. I was shocked at first. On the dyno on the same day before and after pulls showed no hp/tq gain. However, at the track with very similar DAs I went from 119.5mph to 121.2 consistently. and from 11.36 to 11.23. And the new owner has been 11.20 at almost 123 mph.

Every car has the potential to react differently. I took the advice of Joe Overton who at the time was running the quickest and fastest n/a LT platform around. And when I bought them there was only a $20 difference in price. My car ran its *** off in ET and mph for what it was and still does. I'd like to think it was from making the right choices for the entire combo. And those headers damn sure helped. The difference between the 1 3/4 and the stepped may be negligible, but if price allows why not run a header that will handle everything you'd want to throw at it later on? And plug changes were actually easier with the Kooks over the 1 5/8 because of how the primaries were run with the smaller headers.

--Alan

adamc

iTrader: (1)

I put the Kooks stepped headers on my 94 formula. they fit like a hot knife through butter. they lined up and fit very well. worth all the money.

FASHOOTER

iTrader: (4)

My 383 made 388rwhp with KOOKS 1 3/4. Switched to KOOKS stepped 1 3/4 to 1 7/8 made 411rwhp on the same dyno. Nothing else was changed but headers.

96capricemgr

iTrader: (1)

I have not seen what you guys are seeing. Then again my headers are for a completely different chassis and chassis is a BIG part of header design. My car has also never been dyno tuned.