Welcome all 928 forum refugees!
User avatar
By Shifted
#13381
I thought that it might be fun to have a thread on the various power enhancements that we've done to our vehicles. The general format would be:

Modifications
Why you chose them
Who did it
What you believe the before and after power to be (estimated or dyno, whatever).
Would you do it again or recommend it

I would love to hear about other people's setups.
User avatar
By Shifted
#13382
For my car:

As bought in 2009:

Modifications: When I bought the car in 2009, it had a cross pipe, no cats, S3 profile cams and an Autothority EZK/Ignition chip (no LH/fuel chip)

Why: I didn't choose them :)

Who: Motorsport LLC in Salt Lake City, UT

What: I have a copy of a dyno graph done in 2005, four years before I bought the car. It shows the max power as being 287 whp and the max torque at 291 ft lbs. I used PerfExpert and Virtual Dyno and came up with similar numbers in 2019.

Do it again: Yes and no. I definitely wouldn't have put in an Autothority chip. But I do like the S3 profile cams. The cross pipe was nice and seemed to give a little more power and had a great sound when combined with a rear muffler bypass. I really enjoyed the combination.
Attachments
2005 - 928 Motorsport, Salt Lake City UT Dyno Run.jpg
Last edited by Shifted on Sun Aug 30, 2020 5:48 pm, edited 1 time in total.
User avatar
By Shifted
#13384
Now:
Modifications: S3 profile cams, mid-mount turbo (CompTurbo 6767 with .82 AR) producing 11.6 psi, air to water intercooler, SharkTuned EZK and LH computers, SuperMAF, Bosch 044 fuel pump, Siemens 60 lbs fuel injectors.

Why: I like how uncluttered the engine compartment is and how much sooner I can reach full boost compared to a supercharger. I also like that I can return the car to fully stock with no permanent modifications to the car other than five small mounting holes that I put in the firewall. I especially enjoyed the challenge of doing it myself.

Who: I did everything except the exhaust. I had Colin Jensan weld up the exhaust pipes from the stock manifold outlet flanges to the muffler. All other fabrication, design, tuning, modifications and all installation was done by me.

What: I have only used PerfExpert and Virtual Dyno to measure the performance, but it appears to be making around 520 whp and 510 ft lbs of torque.

Do it again: Definitely! And I would recommend it to anyone who would enjoy the benefits of a turbo. Especially if you want to do it yourself. It drives great at any level. The only thing that I might want to change is the muffler to tone it down a bit.
Attachments
928 - Before and After Turbo - 20200822.jpg
User avatar
By SeanR
#13410
Power wise, I started by getting the car to run as it did from the factory.

X-pipe/small resonators/GT muffler.

VCB Supercharger with Sharktuning. The VCB was the cheapest option and Victor needed someone to demo it so he could sell a bunch so I gladly took that opportunity. RWP was 370hp at 5psi. Could go smaller pulley but if I'm going to change it up I'll go Twin Screw or rear mount turbo. Turbo may be the best option considering who I have around me here.
User avatar
By Shifted
#13416
I've heard of Victor's setups, but never seen one and have no details on them. I would love to know anything that you feel like sharing. Photos too.

You said considering who you have around you...who do you have around you and how does that affect the turbo vs supercharger decision?
User avatar
By SeanR
#13421
Shifted wrote: Sun Aug 30, 2020 7:49 pm I've heard of Victor's setups, but never seen one and have no details on them. I would love to know anything that you feel like sharing. Photos too.

You said considering who you have around you...who do you have around you and how does that affect the turbo vs supercharger decision?
He's not producing them any longer as life got in the way. Rotrex SC.

Image

I have ATS Racing here in Denton and they are known for some seriously high power MR2's and a few Ferrari's. He's currently doing a turbo set up on a customers 928 right now.
User avatar
By hessank
#13885
Alpha-N tuned, so Mafless
Headers, X-Pipe, Flowmaster rear muffler & quad exhaust
Blackbird intake wannabe
Mini hi-torque starter
C5 Z06 Tremec 6 sp
Image
SeanR liked this
User avatar
By Shifted
#13893
Sean, that's a really nice looking installation. Interesting decisions on the pipe routing and sizing.

Hessank, if there is no MAF, what is it using to determine load or air flow? How did you get the Z06 transmission to match up to the 928? Did you buy a kit or...?
User avatar
By hessank
#14241
Shifted wrote: Tue Sep 01, 2020 10:58 am ....................Hessank, if there is no MAF, what is it using to determine load or air flow? How did you get the Z06 transmission to match up to the 928? Did you buy a kit or...?
You can read up on alpha-N here: http://www.jdsporsche.com/sharktuner%20alpha.html

There are about 5 of us with this 6 sp mod. Just do a search or PM me.
User avatar
By Shifted
#14248
Cool. I remember seeing the Alpha-N system when I bought my SharkTuner, but since it didn't apply to me I didn't look at it closely. That's a pretty cool system.

I've seen the 6 speed conversions and am aware of 928 Motorsports kit. If I need a replacement transmission and can't get an OEM one, then the 6 speed conversion looks like a good option. However, I would prefer to do the fabrication myself.
User avatar
By SeanR
#14249
Shifted wrote: Wed Sep 02, 2020 10:45 am Cool. I remember seeing the Alpha-N system when I bought my SharkTuner, but since it didn't apply to me I didn't look at it closely. That's a pretty cool system.

I've seen the 6 speed conversions and am aware of 928 Motorsports kit. If I need a replacement transmission and can't get an OEM one, then the 6 speed conversion looks like a good option. However, I would prefer to do the fabrication myself.
As well you should.
User avatar
By Polecat702
#14283
I have the same VCB setup as Sean. I like it! I'll add the intercooler this winter, as a precaution, for the Las Vegas Desert heat. Been over 110 for the past 6 weeks. Haven't taken my Shark outta the garage since the heat wave started.
User avatar
By hessank
#14629
Shifted wrote: Wed Sep 02, 2020 10:45 am...................... However, I would prefer to do the fabrication myself............
Absolutely!

Looking really good! You must be excited :)

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