GregBBRD

Yes. And the data from Sharkplotter is even clearer.

You can see it all on one page.

Even I can tune it!

GregBBRD

Here's a few promised pictures.

This is one with the trays on.



Here's a shot from the rear.



Rear tray off. (Air injection not hooked up, in this photo.)



Driver's side.



Passenger side.



Side view.

Rob Edwards

Steve looks sad that he's all done putting them on and taking them off and putting them on and taking them off and putting them on and......

terry gt

WOW ! That is a work of art ! What are the plans for more systems ?

Darklands

@ Greg
Why did you install a H after the headers and a X before the mid mufflers?
Is this design decision power related or to little room in the front?

Is the first run also with a sharktuned engine management?

Thank you for sharing informations from this great looking install!

GregBBRD

The header jigs are almost done with a second (almost completed) set sitting in the jigs. We will have the third set built completely off of the jigs and test them for fitment. All of the pieces are sitting in house to build the first ten sets. The complete stainless exhaust system that is in the pictures is a version of the system that we have been building for our cars for a couple of years. It is going to be CNC duplicated and will be available for use with headers and for use with stock manifolds.

We will be testing the headers on a stroker, in the next couple of weeks, to see if these pipes will "light up" a 6.5 like they do a 5.4. [This entire project is the result of some very intensive testing (two months of swapping everything we could swap) on a stroker engine to see if changes to pieces had any effect on power. We basically found out that the stock manifolds will limit the power to about 415 (flywheel) horsepower....regardless of anything else you do to the engine (no power adders.)]

They next set goes onto a stock 5.0, to see what they can do there. That engine then gets "tweaked" with cams/head work to see how it does.

These individual tests (GTS done) will give us real life/real world feedback, combined with any fitment issues.

The first six or seven sets already have homes...anticipating that all the testing will be positive and the people that have expressed desire still have jobs....

GregBBRD

Completely mathematical exhaust theory. Our prior x-pipes were located in front of the cats...

No, the GTS was not Sharktuned before...it was stone stock. It is a very low mileage vehicle. We confirmed that it got full throttle and that all of the injection pieces were properly working. The fuel mixtures were very good (stock). It did have the "typical" roll on throttle pinging that the GTS models seem to suffer from. We actually removed a considerable amount of timing, when we Sharktuned it, after the headers. If the engine were to be rebuilt and had the piston/ring problem addressed, considerable timing/power could be added.

svp928

I have an 85 you can test them on.....

SwayBar

Beautiful looking work!

JWise

Beautiful work, Greg! Impressive gains, particularly when considering the typical GTS issues leave more on the table still.

You mention testing on a stock 5.0L next, I presume a S4. For obvious reasons, I'm curious as to how a GT would react to these. Perhaps the 5.0L runs after cam and head work will give a better picture as to how a GT might respond.

I'd really like to see what a normally aspirated GT is capable of with bolt on parts. I think I have a pretty good engine to start with, and future plans include intake, exhaust, and Sharktuning, but no cracking open the engine.

Perhaps I missed it, do you have any info on pricing yet? PM if you prefer. Thanks in advance.

William A

Impressions after a long weekend reunion:

I can't get enough of the sounds. As much as I love race cars sounds, I didn't want to be driving one. Greg's setup gives just a teaser at startup and as you roll up through the gears at a street legal pace leave the impression that there is alot left under the pedal waiting to get out. And the video and audio Rob posted tell the story at WOT! It is not manic or feverish sounding, and no droning at any speeds! Stays true to the GT DNA of the 928.

I am a numbers guy in my business (not automotive!), but numbers don't do justice to the enhancement of the overall driving experience. Greg's comment before I drove it was that it will feel like a different car. He couldn't have been more right on. The car has never run better, pulled harder, or pulled longer. It used to feel like it wanted a higher gear at around 4500, now it just wants to continue to run out close to redline. It spools up so freely, when before it felt like it had a governor at certain points.

I am so high on what Greg accomplished, that I'm am feeling just delusional enough to expect that my GTS has stopped burning vast quanitities of oil thanks to his new exhaust system, lol!

If anyone is interested, I'll try to post more pics or video.

kccampro

That's pure beauty right there.

GregBBRD

Still not perfectly clear, but looks like right at 3K for the headers. I'll know for sure, when they come off the jig.

ptuomov

Great headers and a great product.

ptuomov

Are these dyno graphs / power gains comparing the stock exhaust manifolds and stock "cat back" to your new headers and new cat back? Or just the headers? I am assuming the former (i.e., complete exhaust swap).

Also, how much would you guess came from tuning and how much from the exhaust? Or was the first run also tuned to give the best results with the stock exhaust?

Obviously, these are great results, great headers, and a great product. By a great product I mean it's not half baked in any way: Trays fit, smog inspector can't see the changes, even if he would see them its basically legal with all the emissions components there, cool looks, and brand name to back it up.

Very interested in seeing the results with other engine variations.