slate blue

Well from its humble begginings, my project is coming along albeit slowly. I didn't realise 5 years ago what I would do and what it would compromise of. I suppose one of the motivating forces was the snidy attitude of 911 owners towrds the 928. When I was an apprentice earning $100 a week and the 928 was about $50K here so I thought I would get one, one day. Problem was when I did get one it was a bit out of date. But as we know they have great bones, I knew that it could still challenge todays great cars, sorta like a athlete that hasn't been training and been on a diet of Krispy Kreme and McDonalds. What to do to whip her into shape.


(Work that has been completed)

Add better suspension,
bilsteins infact
993 twin turbo brakes and new S4 master cylinder
996 lightweight five spoke wheels with Pirrelli P zeros
Custom control arms that keep the scrub radius close to factory spec
New bearing in the torque tube
New twin plate clutch
GT Gearbox with oil cooler
Convert battery box to S4 spec for twin 3 inch exhaust with variable backpressure valve, exhaust will be lighter and ceramic coated, lighter weight battery used
S4 brake and Abs sensors fitted for traction control system
New stereo system Blaupunkt Nevada with custom woofer
Done away with spare tire, puncture repair kit and air compressor to echance sound system and save weight
Repaint and retrim entire car to concourse winning standard

Parts that have been acquired

GT engine
Cams from the 86.5, better cam spec on the intake
GT air cond compressor
Under body aero aids from S4
Twin thermo fans from S4
944 turbo forged conrods
Genuine Porsche boost guage for the 928.

Research done
Modify GT heads to GTS spec. Will use GTS head gaskets.
Supercharged with a twin screw autorotor is the way I will now go
Aircond. system used for intercooling, better cooling and hopefully less weight, engine will have twin intercoolers, possibly use electromagnet clutch on compressor to save wasted energy
Remove all internal sound deadning and save plenty of weight

Final front splitter design just probably a small lip to enhance the aero effect, better brake cooling and engine cooling, also doesn't impinge too much on ground clearance abilities.

I hope that the car will weigh in at 1500 kilos curb wieght and the engine to reman very drivable but produce in excess of 650 hp, but more importantly produce plenty of torque down low to move this 1500 kilo car. I am chasing a ten second quarter, after all this work anything less will be failure.


Please feel free to chime in.

Peter F

Hi Greg,

Wooow, I'm impressed of your ambition level here!!
Can you tell more of the oilcooler setup for the gearbox?
Any pic's to share.

/Peter

GoRideSno

Sounds like fun Greg.

I am now an Opcon Dealer, including Laminova and Autorotor brands.
I have also designed and built 2 different Laminova intercooler designs.
I have 42 cnc machined end plates.

Let me know if I can help.

Andy K

bcdavis

Sounds like a cool project.

Why would you need a carbon fiber intake manifold, if you are running an autorotor?
Or are you talking about a CF air intake for the supercharger?

goliver

Greg,

Looks great. Any info on your wheels? What are the sizes and offsets?

Regards,

rob rossitto

WOW!

SharkSkin

Gorgeous... you've really updated that shark! Did you take any pics during the process? Sounds like a lot of interesting stuff goin' on in your garage.

GoRideSno

Greg,
Post the pics you posted back when you first finished the car.
Thx
Andy K

Vilhuer

What is basis for this number? Why not 7500 or 7000?

Want to know more

How's closing done, pressed in plate, welded...? What block cement product you plan on using?

Want more details

How exactly is this done It's top secret it seems.

What, where, who, how. You get the picture.

Huge project you have going. Other 5 years and it's almost there.

stuartph

Greg


Thats one cool spec your car will have when its finished and its looking great at the moment to.


If i can get my **** into gear i'll get the bits done to my GT one day





Stuart

GT UK

Lagavulin

WOW...

I can't wait for both blau928's and now your car to be finished; both should be something else!

Jim bailey - 928 International

The GTS trans uses an external air cooler not the heat exchanger in the rad. , The GTS gears are hardened but I have not seen that that is true for the GT . The GTS box has internal oil spray and a hollow pinion gear for cooling . The PSD can be locked with a bolt BUT it seems it increases understeer in tight corners .

slate blue

Hi Jim you are quite correct in that the GTS uses the external oil cooler, that is what I'm useing too. Although in the early models it is a different shape and mounted low.

I checked all I could about the GT box before going with it, as you are no doubt aware the GTS box is very rare, plenty more GT boxes out there. If you check the part nos. you will find many of the gears are the same. As you know the GTS has slightly different ratios, but I can't imagine them useing some hardened and some not. The way they cut the gears in the GT is the same system as the GTS. I not sure about the spelling but something like klingelnberg Palliod tooth system, it is very expensive to produce the gears like this an requires a special machine. The GT has this special process.

Also because the part nos. are the same the GT box has and I quote the Porsche service bullitin, "The new 17CrNio6 gear material is suitable for higher continous loads. In addition, the surface of the tooth faces of the loose and fixed gearwheels has been compacted by wire shot blasting to increase load capacity even further."

Inregard to the bolt setup, pros are it is very cheap, it can act like a spool for very stable handling, Cons it can increase understeer, it will increase tire wear, it is not as efficient as putting the power down as a torque biasing differential. A torque biasing diff would be quite expensive as it would need to be custom made.

I also plan on doing some of the GTS upgrades like fitting a spray bar, but this job just seems never ending.

Chuck Schreiber

Greg,

Absolutely Awesome car!!!!

Boy, I thought I put a lot of time and effort into my 79!!
I wanted to find out more about you grafting in the GTS battery box.
Mine is pretty much toast from years of battery acid eating it away. Is the GTS/S4 box just more shallow to allow the running of "true" duel exhaust??!!

A New box has to be welded in place (I'm assuming) so I've been thinking, why not go with the later model box so I can add the exhaust I really want.

Let me know how you did it!! Thanks.

slate blue

Hi Chuck, first you need to strip all the body coat off that covers the spot welds, then drill a pilot hole through all the spot welds. After you have done this use a 6 mm drill to finish off all the spot welds. You will probably find that you need to split some of the welds as they are still hnging on.

Becareful when you hit the welds not to cut up metal that will be remaining on the car! Sacrifice the old battery box and when you take the S4 battery box from the donor car do the opposite. Sounds basic I know but saves you work and gives you a better finished job. I then lined it up, checking it everywhere, do about four spot welds, I used a mig for this to do the preliminary positioning. Check it again, N.B. you will probably need a jack to hold it in position for this step.

After that weld all the old spot welds up, I used mainly mig but I also used an oxy where it would tight and hard to grind back the excess metal, the oxy allows better control in close quarters like that. Make sure you deoxidine all the exposed metal then use a good etch primer and then some 2 pack primer. Then you can use body coat, Wurth is good stuff, and for this use a gun and brush. I think I also used some seam sealer. I then used some paint I had left over from the respray and touched everything up. About three days part time work in all. Good luck.