Currently I am running pacesetter longtubes made for a 2002 F-body 1 3/4" primaries and 3" collectors to 2.5" exhaust with an X-pipe and 8" bullets. Do you guys think it's worth jumping to a 1 7/8s header or 2" header and 3" exhaust ? The speed engineering 1 7/8s swap headers really look like a great deal to me.

 

I will be tuning for a 150 or possibly a 200 shot in the near future, and I have been told I need bigger exhaust from the primaries to the exhaust itself.

 

Scrap the pacesetters. These numbers 1-3/4, 1-7/8 are measured from the OD of the primary tubes. The ID is what allows the exhaust to flow. When you pull them and take a look at the inside you will see what I mean. Nasty welds extending into the tubes making every tube different and an obstacle for the flow to pass through at the flange. I got some Texas speed 1-7/8 beautifully done on the inside and out but with my luck as it can be just broke a weld at the tube/collector drivers side and is leaking liking like a sieve. Can you say carbon monoxide poisoning.
For max power run open headers or leave it the way it is and just add more nitrous. Anything past a tuned collector(Dia/length) is power lost.

 

Should be able to use the headers, not perfect but will work well. Swap out the rest to 3"

 

Kooks 2" x 3.5" long tubes. There is no substitute.

If you got big power I believe they have 2 1/8" now too.

They have stepped also. 1 7/8 to 2"

They also have complete exhaust systems too. Fitment on everything is assume. Easy plug changes. Its expensive for sure. But your getting what your paying for. Ask anyone that has them, if they regret spending the money. All made right here, in the good ole USA. And a sponsor too.

 

What do you run now ?

I kept being told my exhaust was too small (1 7/8" x 3" headers, 2.5" H-pipe FlowMaster system) and it had me guessing.
One day at the track I lost a muffler and tailpipe, so what was I to do ? Remover the other one Less than a tenth change in ET and less than half a MPH.
Frustration sets in after a few passes, remove the H-pipe, so now open headers (LOUD)!
After all said and done, it was less than .15 faster (guessing due to weight).
A buddy with a LOT of track time in his low 10 second nitrous SBC Nova told me a 3" system over a 2.5" system was only worth .2....but you know I had to try.

This was all done NA and in 1 day at the track....so I guess I'm saying, run what you have and see where you land first before buying a bunch of stuff you may not need.

 

Doug you are absolutely right. I would use what he has for now too. N/A on a mildly modified motor prolly wouldn't pick up much. But on a 700+ HP motor being sprayed with say 200. Will way benefit. Will be a lot of room to build. Which everyone ends up doing. And you know as well as I do, many have lost to less than .2 I would be shocked, if a full Kooks system would only pick up .2, compared to the full system he has now. Nothing wrong with having a wish list. Best of Luck on whatever you choose.

 

Thanks guys, I'll definitely wait on upgrading that stuff.