Carl Fausett

Geez! My spelling sucks! Sorry guys...

Scott M.

Since I like to instigate things...

Here are some observations from this weekends Frenzy:

1) A 79 euro from Montreal, 80 US short block, Euro S heads and Cams, L-jet (not a blow thru design) Vortec V-1, FMU did 233 rwhp and 314 rwtq on a Mustang dyno. Car was seriously out of tune but a rather elequent design.

2) One SC'd 89 S4 got flat bedded home today, due to a Fubar'd crank bolt. Likely due to, either a bad crank pully design or an installation error. I'm gonna stick w/ a bad pulley as the owner will kick my AS$ if I say otherwise. (And BTW, I think you owe me gas money dude)

3) There is a particular Brit (from Germany) with a permanent grin on his face after driving the "Worlds quickest, street driven, 5 spd, lowest mileage, dark grey, northeastern, pump gas stroker".

And...strokers are more reliable.

Scott

Carl Fausett

Scot M - stir, stir, stir...
...I'll take that challenge! I'm 1/2 way done with a SC on an L-Jet right now.
I think I will do better than that. We'll see how she comes out when I am done.

shaaark89

well, that was me. after investigating this evening it looks to be an owner install error. looks like in my haste to get done for the frenzy, i just plain made a booboo on the crank pulley install. paid for it with a trashed damper (pulley was spinning on the crank bolt and chewed it up,) a way fubar'd crank bolt, and some mild damage to the crank threads (hopefully can be chased out without any problem.)

yeah i know. also a run in the rs6. that gives you an excuse to come down.
seriously though, thankyou very much for the help.

having driven that car as well, i can attest to that.

hmmmm..... seem to remember something about a clutch last year?

heinrich

Please play nicely Guys, I think all 3 SC vendors are respectable. Personally I think attacking each other like this is bad form.

Carl Fausett

Heinrich - you are right. An open information exchange is good. Personal attacks not good.

Besides - this thread is supposed to be Stroker vs Blower. Somehow it became twin-screw vs centrifugal again.

BrianG

Right on, Heinrich!!

This thread, and previous similar ones remind me of the old 2-stroke vs 4-stroke debates of my early motorcycle days. The fact of the matter is that power can be made in a number of different ways, and that each way probably looks (dyno) and feels (seat-of-the-pants) somewhat different than the other. It's all a matter of personal preference and/or proposed application. There's also the more esoteric matter of "sexiness" of the installation, and THAT's about as subjective a factor as you can get.

I know why I chose the S/C that I bought, and I doubt that I'll be displeased with the results of my Mega-Shark when it's done. It will have been a stimulating exercise in advancing the smile-quotient of my favorite car, it will have increased my knowledge and understanding of the 928, and of the issue of supercharging in particular, and it'll be a huge hoot when I go cruising with my buddy with the newer Carrera 4 again! And ya know what......... I won't really give a hoot if someone's dyno-chart has a bit bigger bump than mine, or someone's strip slip has a bit smaller number than mine. I'll have learned something new, and have a toy that's more fun than it was before I got started.

All I want out of this exercise is exceptional customer support, and high quality goods from the vendor of my system. I don't have any reason to expect anything other than that from any of the guys found here on this forum.

As far as all this macho dialogue, and the attendant bravado is concerned.......... it's like an old university Prof of mine used to say.... "All of this stuff is either obvious or trivial.... get over it!"

Stan.Shaw@Excell.Net

I know strokers have been run on the road racing courses for years, but I struggle to find evidence of supercharged cars with any road racing or even drivers education event use. I know Carl has some, but only with 16V motors, correct?

I certainly understand that the primary market is for street driven cars, so perhaps the road course use just won't happen...

I consider the idea of supercharging a motor for my race car, most likely either an '86 or an S4 motor. However I am realistic, and know my budget won't tolerate too much R&D. So, while I know the stroker route is a fairly certain path for a 928 to be road raced, is there ample evidence that a supercharged 928 will be as reliable and long lived.

I get particularly concerned about discussions of heat, since I have had heat isssues in the past with my 928 on the track.

Thank you all for your efforts in improving the performance of the 928!

CMW

Hurray for as all.

No seriously... all have their pros and cons... quite literaly.
We all take chances with modifying our cars.
It seems there should be enough business for all of you. I mean the big three have survived, and from my understanding there are really only two SC vendors if you count the Quick Carl and Tim Murphy as one and then Andy's Supermodel as the second.
SInce I have had both a Vortech (never on the car) and now the twin screw I have some opinions.
So far I like the twin screw better... but that is because this kit is right and the Vortech "kit" from
Eric M was not complete or supported. As I've said before I think the kit was sound but the man was not. I don't think anyone here has anything to worry about from Andy or Carl.

Remember there is stregth in numbers and unity and as American's (as well as others) we also like our diversity. Stroker, X2 Screw, or centrifiugal they are all doing what we want for the car and that is keeping the greatest GT of ALL TIME... literaly up to speed with "latest and greatest" of a new (garbage) generation of cars.

heinrich

The reason there are no racing examples of supercharged cars (racers know this I assume) is that supercharged cars change the class of race car to no longer normally-aspirated and no longer stock etc. Another excellent reason why a supercharged car cannot be found with race miles is that only the past year or so have supercharger setups been becoming mainstream and inexpensive for the 928.

hacker-pschorr

The motor I'm working in will be supercharged for track use. I do not plan to race, just DE's. One of the groups I will run with (speed seekers) is an F-Body club (lots of pony cars and vette's). There are quite a few SC cars running in that club, so it can be done successfully.

Stan.Shaw@Excell.Net

Heinrich - With regards to PCA club racing, I don't see the class as a real issue. Multiple classes are on the track at the same time, so you are really racing whatever is out there. Whether you run GT2 (NA) or GT1 (SC) you will almost certainly be on the track with the same cars. My racing experience is limited to PCA for the past 4 years, so I realize other venues may be different.

Even though SC 928s have only been around for a year or so, I was hoping someone would have taken such a car to a road course a few times, and could provide some real feedback.

Eric - Your experience will be interesting and useful, I was just hoping for something now.

Thanks again!

heinrich

Not that I am necessarily more or less qualified than anyone else to answer this question, but I helped put one together and have ridden in one. At least for the positive displacement unit, the car looks, sounds, responds and feels almost exactly like it did before, except in one aspect: It seems to be more powerful, more torquey.

I understand this sounds simplistic but it's the best explanation I can give. The torque curve is granted, very very flat as opposed to a n/a car, but the feel of the car is not one of kick, boost or gangbusters. It just feels like the same car, only far more powerful. In other words, it feels simply like a bigger-displacement engine. And it sounds like one too. I imagine I can hear the air being forced through the system and exploding through the exhaust in explosions, ie more raspy than before.

I'd go as far as to say that with the sc I've experienced, the car feels far more smooth in its torque delivery, since there are no flappies and other artificial induction tricks to raise the torque curve along the way.

My impression of the 85 86 cars is that they come on really strongly in n/a form, at about 3200RPM. With the sc, the car does not do this. It appears to have lost the low-end induction inefficiency, and at 3200RPM, continues very steadily on at the same rate. Very smooth.

I do understand that with the centrifugals, one would expect nothing like that, but I have seen expectations shattered where this kind of thing is concerned, so I cannot comment on those units. I have driven turbocharged Porsches and personally I find the very smooth and predictable delivery of the sc I've worked on, to be more along the lines of what I enjoy, ie a road car, very mild-mannered but (be not mistaken) a monster. I call that a street rod.

IMHO, when you remove the induction Porsche engineered, the 32V models become a lot more similar, except for the obvious valve and cam differences. But induction is no longer a factor.

So, as it regards racing and autocrossing, there can be no reason why (given governing body acceptance) a supercharged 928 could not be very successful on-track. Heat is your enemy, but otherwise I can't see a problem. Heat can be managed.

Stan.Shaw@Excell.Net

Thanks again for the thoughts.

I am looking for someone who has already used one in some way similar to how I might. Only then can I know that my R&D costs will be kept within my budget.

Shane

Once I get my brakes upgraded I'll do that for you Stan. I ran mine at spokane raceway park this last Sept. but I'm sure I didn't come close to running around the track for a long enough session to give any real feedback. How long are your races? How many laps?