surf808

Hey. I am having trouble deciding to go with JBA LT with catted H or Kooks with cattted X. Which do you think will sound better with the MAC mufflers that I already have.

Thanks.

69_gt500

I would go with an H-pipe. IMO the macs sound raspy with an X-pipe. Another setup to consider could be American Racing longtubes with catted h-pipe.

SlamMan02

I went with an X pipe originally and am currently thinking about welding in a Prochamber to make it deeper... Take that as you will

surf808

SlamMan02 how are the bbks. Is the fit and sound good?

SlamMan02

I love them! The sound at WOT is absolutely amazing, I just wish it was deeper for normal driving- Hence the reason Im thinking about ditching the X to weld up a semi-custom catted prochamber setup to match up with the BBK LTs and Pypes MM

Rudiepoo1

I think between your two choices the JBA setup with the H would probably sound the best. As already stated the X pipe tends to bring out much more raspiness.

Mikes_BLK_GT

Kooks comes with an H as well

surf808

Hmmm. I just wish MAC had a catted prochamber for their long tubes.

SONICBOOST

Its actually not quite that hard to make a catted prochamber. Check this out

Not mine




I cut off about 9" of the downpipes and spliced in the cats. My O2 sensors barely reach the bungs on the rear of the cats, but they should be ok. I used some aluminum wire to fasten them to the sides of the transmission. The cats came with plugs for the O2 bungs, so I used those to plug the two bungs on the downpipes. The only real problem I had was that one of the band clamps Pypes sent me was missing the curved washer where the nut goes. I'll get a new one sometime and fix it, but for now, it's holding without it.

Here is the offroad prochamber before modification.



A close-up of a cat.



Overlay of the prochamber and stock H-pipe.




After the modification and ready to install.

m05fastbackGT

You did a really nice job with the modification. I also like how well the Pypes cats look with the Prochamber, as they're more downstream the pipe than the CATCO cats are on mine.

SlamMan02

That isn't his, but it is no secret that I am definitely toying with this idea...and I would definitely spend the money if it wasn't for a friend of mine selling his D1SC Kit with brand new seals/bearings from Procharger asking 3500 with Fuel upgrades, Intercooler, etc.

m05fastbackGT

It sure looks good though. Especially with the cats being further downstream, and completely off the downpipe section.

ETNOATS

Im running this set up, except using ebay cats that look just the same, hooked up to stock manifolds. Originally the cats were still a little to quiet. So I drilled out about 1 inch hole all the way through the substrait. Sounds really good, loud, deep and no raspiness or trumpeting. With the cats out it was louder not as deep and did have the raspiness around 1600 -1800 rpm. The hardest part of this set up was getting it all lined up. I still have a couple leaks I need to fix but you can barely hear them over the exhaust. I have been waiting to hear what long tubes with the prochamber and mac axelbacks sounds like.

surf808

I was talking with Brenspeed and he said the JBA long tubes are hard to tune because of the position of the o2 sensors. I was just wondering for anyone that has them are you getting codes or anything.

SlamMan02

JLowe! runs JBAs with a catted H

SONICBOOST

The only thing i don't like about the cats in that picture ( pypes cats) is they look a lot like the dynatech cats ( pic below).

Imploded and blocked cat






Path of projectile when cat blew it's wad













The cat slug stopped when it hit the O2 sensor in this bung




The Results

Rod thru block

surf808

Just curious how much do you think it will cost to get my own cats and weld them to the prochamber?