69gaugeman

Pick up an 87 block with squirters and boost away, selling the GTS motor to pay the way.

By the sounds of it he wants another 100 crank HP. This would be a low pressure turbo application (or mid pressure, depending on your definition) to which the 928 motor SHOULD hold up just fine. Head deck condition (no corrosion near the fire ring) should be a primary concern. Every head gasket failure I have seen on this board is due to that condition. Not saying that boosting didn't kill the head gasket, but it seems a little far fetched considering the quality of Porsche materials. I would be curious to see a failure mode on a head gasket that WASN'T related to the blowout under the fire ring caused by corrosion... anyone have pictures to help enlighten me?

BIG 928

im guessing another 100hp would put me back on the top spot, if i can use the extra power with the planned wheel/tyre mods.
anymore power would be good if reliable. just looking at all the options you are all suggesting!
i dont know the current hp. standard gts even the ecus, just a x pipe and equal length headers.

the budget should be be big once my old aircooled gt2 racer is sold. someone has nearly done a deal with us so fingers crossed. ive just got to buy a ring and pinion and ecu for my cayman racer then the 928 can get some $ spent on the old girl.

many thanks for all the replys and private messages
what a great place this is!

John Speake

Have a word with Adrian Clark, re strokers.

MeanMachine

Stroker is the way to go.

GregBBRD

I've heard that all strokers are not created equal....that there are good and bad ones of those, too.

Bill Ball

Uh, let me clarify that George's motor is not "pretty much dead" unless George killed it since I saw it last a few weeks ago. George and I have had a bit of a struggle with an attempt to install some aftermarket cams. So, yes, it's not running at them moment, but there's no indication that it needs a complete rebuild from anything I have observed. It's still at 3-6% leakdown and seems generally quite healthy. I think that's a testament to the quality of Jim's original build.

John Speake

Yes, in fact a couple of engines. Fitted with Jenvey ITBs and using JDS ALpha system.

No reliabilty issues with the engine. Using GB sourced cranks and rods, 944S2 pistons.

John Speake

A stroker with a stock intake would get you there......then if you need more power later, add JDS Alpha with M5 ITBs.

Strosek Ultra

I've heard that all strokers are not created equal....that there are good and bad ones of those, too.

Who is creating the good and bad ones?
Ake

Cheburator

Mark,

We made 438 rear wheel horsepower out of a 5.4 GTS engine. Using JDS Alfa-N and M5 ITBs. As far as I know, no one has made more bhp than us out of a standard size 928 engine using normal aspiration. Before we get into the argument, it was done on a Mustang Dyno - the most conservative of all conservative dynos.

Even when not running well due to cylinder galling, I was as fast as a 997TT on the staight at Brands. Should make even more bhp on the rebuild motor. The reason for the rebuild - JE Pistons are a bunch of lying barstewards, but that is a different topic all together... PM me if you need more details...

Btw, for all the others - Mark will not be allowed to Turbo or Supercharge his race car due to class rules...

ptuomov

That makes sense, because unrestricted forced induction would mean that no normally aspirated car would ever be competitive in the class.

drnick

Alex, im not sure that was a fair comparison with the 997. Once your piston rings had scraped away the cylinder walls there was reduced friction

jorj7

And probably increased displacement...


George
90 S4 Grand Prix White (Murf #5)
94 GTS 5-Speed Midnight Blue
06 Cayenne S Havanna/Sand Beige (PASM)
http://928.jorj7.com

BIG 928

ill message you later alex thanks, gotta go to work now.
i would keep it 5.4 if i could get that sort of hp from bolt on parts like cams inlet etc. how i read the rules, i thought it just mentioned mulitplying the cc x 1.7 on forced induction cars to fit them into certain classes? i better take another look before i order x amount of parts i cant use!
thanks for the info as well john!

Cheburator

Yes, you multiply by 1.7 - but you have to have the original engine type of aspiration - my brother and I wanted to race a G-Power Z3M Coupe with a supercharged 3.2 putting out 510bhp... It would have destroyed the field, given that it was actually built by G-Power - suspension, brakes, heigo cage, carbon body panels etc. and came 2nd at a wet Hockenheim in the 2003 Tuner's' Grand Prix, yet the CSCC said "NO WAY!" as the Z3MC was never supercharged from the factory...