the_merv

iTrader: (88)

^^There is no low-end with a Stall on a roll race..

BackinBlack02SS

iTrader: (7)

If it makes you feel all warm and fuzzy that you have some super idle-2 grand power band good for you.

the_merv

iTrader: (88)

^^Diesel!

ChocoTaco369

Believe it or not, most people don't drive these cars to beat the **** out of them at the track 3 times a week. Most people drive them because they like the way they look, they like the way they drive and they like the way it sound. That's why the vast majority of LS1 F-body's, even 10 years after their initial release, are bone stock or bolt-on cars. You're the very, very tiny minority that feels insecure unless you have more power than everyone else on the road. The majority of people out there love low end power because that's where they're spending 99% of their time. I'd consider low-end anything under 3,000 rpms, where is where I spend nearly all my time.

jam01

actually i am warm and fuzzy, im sitting by my fireplace. now i am enjoying a beer and shot. life is good.

2002_z28_m6

iTrader: (10)

Here I fixed this post.
Dont take it personal Choco its just a joke.

the_merv

iTrader: (88)

Lol..

SUX2BU

iTrader: (14)

Here's my $.02
https://ls1tech.com/forums/dynamomet...ts-si-car.html

ChocoTaco369

There is no dyno available there. However, reading your post, it seems the Kooks 1 7/8" headers dynoed roughly the same as Pacesetter 1 3/4" headers? IMO, that means stock internals cars will lose a significant amount going to 1 7/8" headers, and here's why:

1.) Kooks are a much better designed header than Pacesetters. Pacesetters are very small for longtubes. They're an old design. Kooks are equal length headers and are physically longer than Pacesetters. Simply put, a Kooks 1 3/4" longtube should outperform a Pacesetter 1 3/4" longtube. I've seen QTP 1 3/4" outperform Pacesetter 1 3/4" 8 rwhp on the top end and 18rwhp/30rwtq on the low end on a H/C, and since QTP and Kooks are (I believe) both based on the same Grotyohann design, the same should hold true with Kooks to an extent. If you gained nothing on the top end, that should mean you're leaving quite a bit on the table with your Kooks. I'd be willing to bet the 1 3/4" Kooks would have made more power.

2.) Dynos don't tend to show anything below 3,000-3,500 rpm's. If you didn't gain anything top, I could only imagine that you would have lost something significant down low. IMO, it was a net loss at the time. Since you added a large cam since then and you're obviously spinning to probably 7,000 rpm's or more, that'll help minimize the losses, but from what I've read, I wouldn't have been pleased at the time on the performance side (of course, you now have much nicer, stainless steel headers so it wasn't a total loss at the time).

IMO, your post justifies 1 3/4" headers as optimal for most stock CI applications. Can you actually repost that dyno graph since it doesn't seem to be showing in that thread?

NavyBlue99SS

Stock engine = 1 3/4
Heads, cam,higher compression, intake, boost or nitrous = 1 7/8

Cant get any easier than that now can it? Most guys think "bigger is better!" and they are WRONG

LS1BLKSS

iTrader: (36)

i have 1 3/4 headers now, and i want 1 7/8 headers... my car has
ms3, fast 90/90, stock heads, and a 150shot dyno around 550... what would i gain from 1 3/4 to 1 7/8?

caviness

iTrader: (14)

i think everbody is to caught up in the header debate it dont make near as much difference on the lsx motors as the old school sbc and thats where it all started.
i belive if you going to mod your car get big as you can afford cause in the end you will need them,if you going to stay 346 na forever 1 3/4 and dont look back but get the best quality you can afford either way.

mikejones

Wow, if his buddy saw it, then it must be true.

2002_z28_m6

iTrader: (10)

Yup now he has headers and a tune and traps 110. Makes alot of sense huh. https://ls1tech.com/forums/dynamomet...re-inside.html

mikejones

interesting

jam01

i thought this site was about helping others, not bashing there heads in with stupid comments.

2002_z28_m6

iTrader: (10)

That is what its about. Except when people say you have to call them on it.

the_merv

iTrader: (88)

There are many keyboard warriors here..

edcmat-l1

iTrader: (10)

We've went round and round with the header deal. Everything we've seen has said there is virtually no decrease in low end performance from using the larger tubes. This basically is as close as we could come to a back to back test. We hope to do some more similar tests.

https://ls1tech.com/forums/dynamomet...s-1-7-8-a.html

Chrome355z

iTrader: (1)

http://www.carcraft.com/techarticles...o_numbers.html

I was an idiot and bought the 1 3/4" headers before I started listening to the "experts" and realized that 1 3/4" loses NOTHING to a 1 7/8" header on a 346, but gains on top.

Unfortunately, even if I did have this knowledge I didn't have the money to purchase 1 7/8" headers unless Pacesetter made some mysterious ones I have never heard about at the time...

If you have the money pound it into your head: 1 7/8", 1 7/8", 1 7/8".