Fastest928

No problem Morgan, strokers in general are not rocket science, however getting them to last and last and getting top power out of them is another story!

A very important part is not just the actual buildup and part selection, but also fuel management and spark control. Later 928 with "halftronic" work well up into the 550hp range. We have seen 6.5l dyno at over 440 rwhp on pump gas, using stock cams and to the uninformed, a very stock looking engine!

We are working on the next level stroker engine at over 600 crank hp or 500+ at the wheels.

Good luck,
marc
<a href="http://www.devek.net" target="_blank">www.devek.net</a>

Shane

Marc,

What options do you have for MY '85-86.5? What would you suggest for Hp increase for those years? I prefer the early body style to the S-4 but would like to have similar or better performance.

Gerry

Hey come on! Give the guy a brake. Just because he doesn't respond the way you would like to an e-mail does not mean he is no good. He is probably in his shop all the time trying to make a living fixing other people Porsches and does not have the time to respond to every ones desire for more horsepower. I have spoken to John a couple of times and I was quite impressed with his technical knowledge and experience with 928's. I might consider a stroker too but he insisted I would blow my early 5-speed trans in about 5 minutes with all the torque. I would need an 85 or newer trany with the Borge-Warner gears in it. At least the guy steered me in the right direction.

Shane

Well that is the kind of thing we were looking for, some customer feedback.

Gerry

What we all need is more options! We need competition for the big three so we can get some realistic prices on parts and services. You ever wonder why a STOKER crank from Scat for a small block chevy costs $400 and one for our 928 from Scatt cost $3000? Its called HIGHWAY ROBERY! They do it and we suckers pay for it because THEY CAN! Maybe if we all stood up and demanded better pricing policies they would get some more business from us! Lets all get some orders in for some damn stroker cranks for say $500 each. I would buy two right off the bat from the first lot. Who is with me on this one!

Steve Cattaneo

Scat will not turn a 928 crank for less than $1500, and a minimal order of 5. There was a post about 2years ago on scat 928 cranks. Count me in.

Fastest928

Shane,
we have had good luck with stroked 85/86 running stock exhaust and putting out about 360 rwhp with a very braod power band. Actually, a broader band than the S4 engines, just less on the top end. We did a local car about two or three years ago and now it has over 40K of hard miles...and serviced just like it was a bone stocker...with a completely rebuilt engine.

Just refreshed our first ever commercial stroker...7 yeals old, over 140K on the clock,serviceed with plugs, oils, belts and water pumps and just worn exhaust valve guides! Match that power and reliability technological combo and I will just begin getting impressed!

And cant wait to see what the stats are on the next generation of our strokers!

marc

Marc

George 911-V8

MARC @ DEVEK: Do you guys have a engine dyno or know of one in the southern california area? I would like to get a 928 supercharger engine on the dyno. Thanks

Curious George

SHRKBIT

</font><blockquote><font size="1" face="Verdana,Tahoma,Arial,Helvetica,Geneva">quote:</font><hr /><font size="2" face="Verdana,Tahoma,Arial,Helvetica,Geneva">Originally posted by marc@DEVEK:
<strong>we have had good luck with stroked 85/86 running stock exhaust and putting out about 360 rwhp with a very braod power band. Actually, a broader band than the S4 engines, just less on the top end.</strong></font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Arial,Helvetica,Geneva">Marc, is that a 6L or 6.5L? Should 360 rwhp sound low to me (it does)? Thanks for the good posts.

jorj7

Curt,

That's about a 47% increase over stock (~245 rwhp)
without exhaust changes. That's not too bad.
I'm guessing that with exhaust, head, fuel, and
ignition upgrades, you should see the &gt; 400 rwhp
figures.

SL8GT

Be sure to consider the area "under the curve" for both hp and tq. Also, consider your driving style in the context of where/when you use hp/tq (i.e., street, track, autocross, etc.) and figure that you can tweek with appropriate cams in addition to what George cites.

SHRKBIT

George,

Thanks for the response. I might have glossed over the "stock exhaust" part.

Rick,

To my knowledge, the '85-'86 cams are nearly identical in numbers to the GT cams, so I don't think they're altogether lacking and I'm not sure what "appropriate cams" might mean to you.

I know of at least one 440 rwhp stroker w/GT cams, so I'm curious to hear more from the source about possiblities with the '85-'86, and why such a low number.

Shane

85-86 928s came stock with 288hp not 245hp. But for my application 360 is a nice improvement.
Be giving Marc a call!
I imagine with headers and such as sharkbit mentioned 400hp is a realistic number without any forced induction. Be nice to be able to lift the hood and not have someone know by looking that your engine is anything but stock.

Fastest928

The only 440 rwhp stroker was built by me using gt cams....and it is a very specially detailed out engine running pump gas!

dont be fooled by cam numbers alone...there is alot more to making power than cams

The 86 is an automatic, no headers or exhaust, no intake mods...just plain brute power with a pwoer curve that does not quit!

Everyone think that peak hp is the big deal....it is not, it always about area under the curve!

drive quietly and carry a big stroke...

Marc

Shane

Thanks for the replies Marc!