Rob, if those are GT resonators I'm seeing, and you have a rear-muffler bypass pipe, it's going to be sex to your ears. But until then, you have to wait until you get home from work.

 

Glad you like it Rob! BTW, the narrow part of the clutch heat shield goes to the front of the car and you shouldn't have had to do any surgery. Wait until you drive it...

 

Rob ... gonna sound like a bat outtas hell and drive like a rocket

 

Just got in from the first drive. Holy crap, what a sound! The butt-dyno says it pulls significantly more strongly from 3500+ up to 6000 or so (in 3rd gear...) I ran out of room to mess around some more but this mod really transforms the car. There's no drone at any rpm, just a good bit more burble that is largely shut out by putting the windows up. But it is loud above 4000 or so! (X-pipe + GT resonators + GT muffler.) 2 thumbs up!

This Impression is Worthless Without Dyno Curves, but there's clearly an improvement. I should probably baseline dyno the car now with Greg now, just to see where it's at.


D'oh! Here I am all cool on the internets, busting out the dremel on a heat shield that I've mounted upside down now at least three times. What a dork I am....

 

I recently installed the same X pipe on my GTS (sourced from Roger) and it went on very easily. Only downside for me was that it spat out one of the fibreglass tapes towards the end of the first track day. I will be getting some custome pipe sections to mate between X pipe and cat back system to remove the need for the tape. Apart from that, I only had to modify the belly pan support bracket to clear the back of oxygen sensor. I also removed the airpump and associated bracketry and belts. End result is a great sound, slight increase in throttle response at higher revs and *brilliant* access to the TT clamp & flexplate. Charles 93GTS & 87 5 Speed in OZ

 

I want an xpipe kit for OB's!

Who will make them?

 

I don't see why it wouldn't fit OBs, I had an OTT design on my '83 with the factory manifolds. Or, if you need/want to stick with the single pipe cat-back, Motorsport offers a Y version, IIRC.

 

The strap clamps can be found in a stepped configuration now, surprised that it appears the ones supplied are one diameter.

 

Dynomax makes those stepped clamps if I'm not mistaken. I'm going to pick some up for my x-pipe.

 

X-pipe is fine for earlier cars as it is, except for the annoying part where you only have one pipe to the back and two outlets from the X. Next available consonant is Y, which coincidentally has the correct number of places to whch you can attache the plumbing parts.

 

Sorry to resurrect this..

But what Dynomax PN was required to fit the Xpipe setup to the stock pipes?

 

Jeff-

Just boxed your X-pipe up, I included the 2 pairs of easyseal clamps that connect the X to the cats and the cats to the resonator pipes. The only thing you'll need is some of the fiberglass wrap and a new set of M8 bolts and nuts for the downpipes. And of course it occurs to me that I forgot to put the test/bypass pipes in the box. Will mail those separately. Headed to Fedex now, will PM you later.

 

Over and above..thanks!

 

I agree James that $420 is a lot for a x pipe.

Dont get me wrong Rob, they are a nice looking set of pipes.
I still think I may get some

I had my H pipe made at the local muffler shop so that I didn't have to run cats
(Sports car = full power - no emissions)

I also had the Y at less of a angle so that the entire bell housing is accessible

Total = $300

 

So you paid $300 for a bunch of metal pipes that improve access.. makes $420 for a proven 20rwhp gain seem like a bargain to me The gains were on my non-cat 89, which didn't have 20 year old clogged factory cats, so odds are a 928 equipped with a catalytic converter will see bigger gains.

Not all x's are equal either - the distance to the X from the engine, angle of entry and exits, pipe size etc. all matter. So for those considering it, the welding up an ebay X onto some pipes to fit your 928 won't net you the same gains.