1LE LS1

iTrader: (1)

gettin ready to order headers for my '02 SS
and i have found some good deals and i have been havin people tellin me to go ahead and get the 1-7/8'' for the long run.

car is pretty much stock with all induction accessories and a catback.
hope to be addin a CAM in a few months

should i stick with the 1-3/4'' and wait 2-3 months on them or get the 1-7/8'' in about a week or two???

NviouSS

iTrader: (8)

if you go big cubes down the road then get the 7/8". the 3/4" will do just fine for a bolt-on and cammed car.

Bryan @ Speed Inc.

iTrader: (19)

well i am insanely impatient... so i'd get the 1 7/8 headers... however, i think for a mostly stock car you should stick w/ the 1 3/4. i believe that to be better for the car's over all performance. i'd still stick w/ the 1 3/4 if i had a mild to moderate h/c set up. unless an adder, HUGE cam, or bigger cubes were involved, i wouldn't get the big headers.


just my opinion... hope it helps

ROCNDAV

iTrader: (100)

What about Kooks 1 3/4 stepped to 1 7/8?

1LE LS1

iTrader: (1)

well the reason i was askin was that i was told by a performance shop that deals with a lot of LS1 cars was that the cars they have tested with the 1-3/4'' vs. 1-7/8'' have all put out the same power...

ROCNDAV

iTrader: (100)

I've been wondering the same. I posted in another thread about putting my new stock metal GM exhaust gaskets next to a set of 241, 317 & AFR225 heads. The ID of the gaskets was way bigger than either GM exhaust port, but the AFR225s are nearly the smae size as the ID of the gasket.

I then measured the ID of the gasket and its < 1.75". I think it was 1.713 or 1.733. So it makes you wonder

I had a 383 IROC that had (IIRC) 1 3/4 Hooker LT and a 3" tru dual exhaust with flowmasters and it was loud but I lost a lot of torque down low. I then switched over to a Edelbrock 1 5/8 TES and Banks cat back and it seem to make more power. Never did the dyno difference though.

I think TTPs site has an explanation of when you should use each, I believe it recommended 1 3/4 for Strokers and Head/Cam motors, and 1 7/8 for large cube motors

Bad Blu Formula

iTrader: (3)

1 7/8" headers should only be used if you have big cubes or if you're spraying alot of nitrous, otherwise, go with a 1 3/4" header for the best results. (That long run idea is retarted, because until you get those big mods, your car is going to be slow )

2002_z28_m6

iTrader: (10)

Interesting but even a stock ls1 likes a big header check this out.

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

ChocoTaco369

this article bothers me. they're only getting 12 hp from stock manifolds to longtubes and NO horsepower from corvette manifolds to longtubes. wtf? something sounds REALLY fishy from that article i think all this article proves is that TTS makes a terrible header. just looking at them makes me want to vomit. they're the ugliest headers i've ever seen.

to the OP: it's simple. if you're going to stay cam only, get 1 3/4 headers. if you're going big cubes or FI, get 1 7/8 headers. my personal opinion is you'll probably see more peak horsepower with 1 7/8 headers, but your low end is going to suffer on a mildly modified engine. at least that seems to be the popular consensus around here. what i can tell you is that the 1 3/4 headers will be a lot easier to install if that makes any difference to you.

that being said, i'd personally go for a set of QTP 1 3/4 headers. the QTP headers will net more power than kooks due to a better designed collector, all for over $120 less if you go for the race version. that's my opinion, but if you absolutely must go kooks, stick to the logic above IMO...

Ripper415

iTrader: (6)

correct me if im wrong but arent the xs headers 1 7/8"? i know there's a ton of people running them with just bolt ons and they dont seem to have problems.

ChocoTaco369

no, they're 1 3/4" and have a standard collector with no merge.

MikeD101898

iTrader: (5)

Sorry for the , but just quick question. What's the difference between race and any other style headers?

ChocoTaco369

race headers have no AIR/EGR provisions. if you have the AIR and/or EGR systems, you'll have to get the codes permanently deleted or your SES light will forever be on. on top of that, you should also remove your AIR and EGR systems permanently from the car.

MikeD101898

iTrader: (5)

Ok cool thanks.

Back to topic, I am very interested to see how this poll turns out. I will be doing a head cam intake etc build, and am looking at headers real soon. Didn't know there was such a difference in the 1 3/4 to 1 7/8. Just figured 1 7/8 would be better to allow more flow. Apparently this is not the case?

Omega Doom

iTrader: (2)

I was told by V6 bird that the 17/8 would be best and that LS1's love bigger exhaust then most think?

lastcall190

iTrader: (36)

I've seen conflicting opinions on this all over the place. "Low end suffering" is the biggest arguement, but I would like to see some dyno/track proof of such. I have emissions 3/4" on there now, and since I've ripped off all the emissions stuff slowly but surely, it's almost a waste to NOT have the race headers. When they come out, stainless is going back in, but what brand/size... hmm...

-J

Asmodeus

1 3/4'ths.

Call a shop who does this stuff for a living and ask.

They are going to tell you 1 3/4'ths.


But I'd vote stepped.

The 1 7/8'ths tube right by the exhaust port will fill too slowly with expanding gas from a bolt on/cam 346 to keep up as much exhaust velocity for scavenging than the 1 3/4'ths. Then step to the bigger tube.

BayAreaSS

iTrader: (10)

1 3/4ths........they are big enough to handle a nice amount of power.

RrCoX22

iTrader: (6)

first pick - 1-3/4
second pic - 1-3/4 stepped to 1-7/8
last resort - 1-7/8 (not exactly sutible for your application)