Rob Edwards

I spent a couple of hours yesterday afternoon to do some more WOT tuning on the dyno at Greg's yesterday. I timed the day well, because they'd just completed the dyno tuning for William's GTS with the new headers and exhaust installed. I followed them over to the dyno shop to watch and listen to the result. Which is out-f'ing-standing, IMO.

First are two audio files of two dyno pulls- I'm still getting the hang of how to record car exhaust audio.

First is from 5 feet back and 2 feet to the side:

http://webfiles.uci.edu/redwards/pub...%205-26-10.mp3

Second is from 20 feet back, outside, slightly off axis.

https://webfiles.uci.edu/redwards/pu...%205-26-10.mp3

For comparison here's my GTS stroker with stock cats, on the tuning dyno at Greg's. Apologies for the wind noise.

https://webfiles.uci.edu/redwards/pu...%205-26-10.mp3


Please listen to these either on speakers with decent frequency response or headphones, it makes a huge difference to your listening pleasure.

Oh, and the video of one of William's pulls.

hacker-pschorr

I had to read the thread title a couple of times.....

Any before / after sheets from the dyno?

Is Greg looking for a 16V customer to do a test fit?

danglerb

I love the growl you get from an X or Y, very much a lets go fast sound.

Landseer

That was good for me.

blown 87

The sheep was cool, sounded good also.

I wonder if you could make that a ring tone?

svp928

Well they both sounded great! Ditto on the dyno results for both cars....

Stromius

Wow...going for a smoke

slate blue

Hi, Did we ever get to see the header design for both sides? Given this is part 2. Dyno results would be interesting too, before and after. I ordered my flange plates this week so it is always interesting seeing the various designs out there. Carry on.

Greg

Ispeed

What's the line? "I'll have what he's having..."

Rob Edwards

Hi Greg-

Sorry, part 1 was here, I should have just appended onto this thread:

https://rennlist.com/forums/928-foru...aser-pics.html

I saw the dyno curves on the monitor from William's 'after' session on Wednesday, but didn't see the 'before' curves in order to be able to make a meaningful comparison. Greg is headed to the dyno shop this morning with a flash drive to get the 'before' curves. I'll post them up as soon as Greg gets 'em.

William A

This was a very lengthy process for Greg, but the results were worth the wait. The fabrication guy shattered his lower leg the day before I brought the car in, just to add some drama.

When he got back on his feet, he couldn't stand for even short periods of time, so Greg brought over a spare motor on a stand for him to work on while sitting down. When the driver's side pipes didn't fit on my motor in my car, Greg brought a rack and steering box, mounted it to the motor, and then the guy could work around the difficult driver's side.

The ultimate goal was to have a complete exhaust that would bolt in place, look very stock, yet increase power. Now that it is all done, belly pans mount w/o adjustment, all heat shields are in place, and nothing was moved or altered from stock that is ancillary to the exhaust system. The only telltale sign is the chrome tips (and a soothing idle burble that belies what erupts when you bury the go pedal).

Have to see the numbers compared to the baseline before, but Greg was pleased with the results. Here are some pics during the process:

slate blue

Very Nice, very nice indeed. Thanks for posting the pics!

Greg

Iwanna928

Beautiful 928 ****!

Looking to seeing what gains where had.

GregBBRD

Dyno results and more pictures will be posted, soon.

This project, although very difficult and very time consuming, blew me away when it was done.

The results are more like we bolted in a completely different engine than just added an exhaust.

Rob Edwards

Ok, got the scans from Greg (it's like the Pony Express- Send Alex with flash drive, back to Precision, e-mail to me, upload to my webserver, post to RL....)


Before:





After: