ptuomov

There's a 928 with 951 pistons and a supercharger in Wisconsin that is over 800 rwhp.

Mark A.'s and Louie Ott's normally aspirated 928s are at 600 rwhp.

John Kuhn's twin turbo kit gets 570 rwhp and near-stock reliability without any internal mods whatsoever. An experienced wrench (not me) should be able to bolt on his base system in a weekend.

In any case, my system is still very much in the planning stages, so me succeeding in building a fast 928 is not cast in stone by any means! ;-)

V2Rocket

any idea what kind of power sterling's 6.4L puts down?

Chris White

one lesson you should take from the modded 951 guys - add as much oil cooling as you can!!!

ptuomov

I think he's builiding it for stage II. He's ditching the variocam heads, cams, and the intake manifold in favor of an itb setup. So right now, nothing. Once he's done, given his short block that can take some serious revs now, he should match Louie Ott's hp by running more revs.

ptuomov

Ok, thanks. That's on the list. Most 928 models have an oil cooler from the factory, but I was thinking about getting a bigger radiator without integral oil cooler and then an external oil cooler.

I am also exploring ways to increas the coolant pressure inside the heads and the block. This will reduce gas build up, which will improve cooling a lot.

Chris White

944 turbos have a factory oil cooler too...not enough! 260+ oil temps on the track...

DEMETRIOS

Anybody can get me the VICTOR_REINZ part# for the wide firering 951 head gasket?
I run 23 psi in a 3.0 motor for 10 years without issues but ineed the gaskets for 928 s4
THANKS

CyCloNe!

Ptuomov just curious on your plans, what fuel are you planning on running? 93? 100? 110? E85? I would think E85 would be a great choice personally.

Paulyy

talking about the original post,
At 20+ psi of boost on the 5L 32 valve engine with an RPM limit of 7200,
Using a twin turbo setup with 2 Garrett GT3076R turbos or now a GTX series turbo, 1000 rwhp is easily achievable...With a good tune obviously.

Tom M'Guinn

I believe it's 99 0922 032 for the 2.5 liter turbo widefire. It's a few drachma more than the non widefire...

George D

What are the other 928 guys using? I know, stock, cometic, and a few others. I've ruined stock, widefire with o-ring, and a cometic. The cometic did allow me to drive the car without boost. The damage looked something like a lightning bolt through the gasket. Without boost pressure, there was little exhaust pressure blowing into my coolant. The car could be driven without boost without issues, in my particular case.

Since we have the ability to have a stainless part between our head and block, why not use a part that MAY allow driveability home once leaking because of a BAD TUNE, too much boost, etc.

http://www.maperformance.com/cometic...c5783-045.html

Your block to head tolerance needs to be about perfect. I tried the sealant on a build. Never again. If going Cometic, spend the money, time, or both to make sure the tolerance is at least within the guidelines from Cometic.

The stock HG with proper tune will last 100K+ easily, as long as there isn't an overheat issue. Since you are now wanting to shove air into your head and fuel into your combustion chamber, you may want to consider additional cooling.

The HG is the least of your build, in my opinion.

Good luck, and looking forward to seeing the progress of your project.

333pg333

George, this guy's thread was dated 2009. Not sure what happened to his build. I'm sure you could check it out in the 928 section.
Btw, we've used sealant before. What happened with yours?

Olli Snellman

You are just fine with original gasket if you have correct A/F and ignition timing values. Quite old thread, i suppose he have already made his choice.

333pg333

I still favour the Cometic when running sustained high boost at the track. The 'drive home' option is too good to refuse.

George D

I believe it reduced the flow in my radiator, and made a bit of a mess in the water passages. When we pulled the motor for the rebuild, there was a crystal film in all water passages. Another reason I went with Evans.