944S2NUT

Beating turboed Hyabusas!! Comeon, I can see the article?

michaelathome

Tony, be gentle with them... Come on.. A 4cyl vs an 8cyl? Two different monsters in themselves.

MoonBoy

Seem topical, and it Porsche Certified! I don't remember where I originally saw this posted or if it's been posted on Rennlist before. I can email anybody the slightly better original .jpgs if desired.

Uh, not 56K-safe sorry about that in advance.

Question:
Why aren't clutched superchargers used more often? It seems like it would be the best of both worlds.

944J

too bad they didnt supercharge the 944na 2v

Clint's 944

Wow, that just answered a few of my questions!!! thanks

Danno

"Why aren't clutched superchargers used more often? It seems like it would be the best of both worlds."

Don't know.. Toyota did it on their supercharged MR2. Got a +30% increase in power and the SC was very transparent, just felt like a car with a big powerful engine. That car pretty much killed off the Fiero.

944S2NUT

The Fiero killed off the Fiero lol.

Legoland951

The last year fiero GT was when they did it right and definitely not something to kill off.

Z

Yes, trying to get better traction on even the fairly wide street tires that some of the centrifugal supercharger 928 guys have on their cars is why some of them had been discussing some of the different ways to control boost, and lower it at the low end. There are a couple of ways to do it, but for the trouble it would be, it's a lot cheaper and easier to just take it somewhat easier on the gas pedal. Maybe you haven't been reading the posts of some of the centrifugal supercharger 928 customers that installed them on otherwise stock engines, with maybe only a cat bypass pipe as the only other modification in a few cases. Here are just a few of a number of similar quotes from some of them:

If that twin screw customer of your's that you mentioned ran 12.5 seconds in the quarter mile without having any wheelspin on normal sized street tires, I guess there's no telling how much quicker than that some of those guys I quoted above might do with stickier tires than they've got now.

Z

How come you keep changing back and forth on things John? One time you say that the centrifugals don't make any boost down low, and only make big boost at redline, and now you're saying that they make too much down low and not enough on the top end. Since Tim's dyno chart above shows his car making a couple of hundred horsepower more than your car at the top end, if that's not enough top end power, what does that say about your car?
With your car being over .5 seconds slower to 60mph than Carl's, I believe that your off the line traction won't suffer.
Maybe you can't, but others have, and not by anything as inefficient as bleeding off boost, like you've commented on in the past.
I do know how easy or difficult it is to remove and install exhaust manifolds on a 928 though. I'd just have to guess how much more work in addition to that installing all of the plumbing, oil pump, intercooler, and other stuff you have on your car would be. Out of curiosity I did take a look under your car when it was in the convention center in Wichita. I couldn't look up and see everything though. I might have tried crawling under a little bit to get a better look, but I couldn't. From the front there was all that plumbing hanging down to within just a few inches of the floor, and from the side there was the puddle of oil that was on the floor under the car. It seems like it would have been a great opportunity to show everyone at that 928 event in Wichita how easy it is to install your kit by putting your car on the lift there at the shop where the tech session was held, and where you already had your car anyway. How come you jumped right out and said you wouldn't do that about as soon as you walked through the door, and before anybody even asked you to?
Wow, your car was over half a second slower than Carl's centrifugal car, and you're going to make a kit now with even lower boost than what you were running then? Speaking of misleading, you did already acknowledge that Carl's car was over .5 seconds quicker than yours was to 60mph, and the times for the 1/4 mile you guys posted were the same, but why do you complain about apples to oranges comparisons when comparing your car to later models, and then tell people your car made 20 hp and 50 ft/lbs more on the dyno than Carl's? You use Carl's dyno numbers from the centrifugal installation on his otherwise stock engine, and then you compare those to the numbers from your freshly rebuilt, nikasil plated, custom forged piston, MAF conversion engine that you then installed a bigger intercooler on. Whenever one of the centrifugal guys posted high dyno numbers you'd say things like:
You continually ask for timed performance results, even offering to send your G-Tech to people to get them, and when performance numbers better than yours are mentioned you go and say things like:
So which is it today John? Do the dyno numbers tell the whole story, or don't they? Apparently the standard for the day is whatever number makes your car look the best to potential customers for you.
That's one thing that you've said that I do agree with John. Always consider the source is good advice. John is trying to sell turbo kits for $9,280, to put on 928s which if in good condition have an average value thousands of dollars less than what he's charging for the kit. I don't sell anything, and it doesn't make a difference of one cent to me what kind of forced induction stuff somebody does or doesn't buy.

For those of you guys that are considering supercharging, I suggest doing some reading on the subject, and don't put that much faith in what somebody that's trying to sell something says without you being well informed. There are a number of books out there, but two of the better ones I've seen are "Forced Induction Performance Tuning" by A. Graham Bell, and "Supercharged! Design, Testing, and Installation of Supercharger Systems" by Corky Bell. Both were published within the last couple of years, so aren't so full of some of the outdated information that some old books are. The first book mentioned deals with the different forms of supercharging, as well as turbos, and also nitrous, rather than just supercharging like the second one does. Good luck!

John..

I'll say this again....Z:

Carl's performance figures are for his race car, with Euro heads, camshafts and 12 psig of boost....not for the kit he offers at below $5,000. That is a fact.

My performance figures are for my car....well before I ever touched it on 8.5 lbs of boost, as it left Callaway in 1983. 4.5 heads, economy 4.5 cams, stock engine internals. An 18 year old installation. The car makes about 70 more horse now, so no telling what the performance is, but it is better....I have not remeasured the performance since the upgrade....honest.

Nobody has any data (power or performance) on my twin setup, because it has not been released, so everything you claim is BS becasue you simply don't know. I suggest you reserve comment on that one because the Callaway is getting a big fat upgrade this winter with my manifold/wastegate/turbo setup and those nice Euro cams Carl used in his race car. Wanna place your bets now on the power it will make? It is a well known fact the Euro cams add 30 NA HP on a 4.5 liter car....soon we will see what they do on the bottle feeder. Maybe we should ask Lag for help on that one because he is always right, right?

Who is misleading now Z? You seem to be such a BMOC here on the list, why not introduce yourself in Kansas? What have you to hide Z, or is that Mike? I made it very clear to all who were there what my name was and what I had to offer, no tricks no BS and no hiding under a screen name. I showed many people all about the setup...all you had to do is ask and I would have gladly displayed to you whatever you wanted to see. You don't like me Z? Frankly I really don't care, but you and others continue to mislead....that I care about. So my car had an oil leak Z, how silly you mention that...it was leaking oil when I bought it in March from Kempthorne Motors in Canton, Ohio...head gasket. It has all new seals now...the underbelly is spotless today.

Z, you talk like you know Corky Bell...do you?

Rogue_Ant

5 year old thread...

DANNiE

Benz has one on the SLK and some C-Class models... Im looking for one myself for my S2... I think its the best route... Plus its capable of being intercooled... and all that need to be done is a injector upgrade, fab up a new accessory bracket and add a new belt with a little chip tuning i think it will add something like 50-100HP easy...

rangerbay

Is the 2.7L block the same as the 3.0L block?

V2Rocket

the S2 block.