George 911-V8

One scientific study after another has proven that people lead happier more productive lives earn better salaries and have smarter less unattractive children when they drive more powerful cars joking!!!!! Otherwise how can you explain all the choices available for someone who's looking to bolt on a few extra or few hundred extra hp. I was wondering what is the choice if a power adder is in the near future?

George

John..

The turbo is still king of the hill George! Strap some on and blow that pushrod beast you drive.

Randy V

A statement, or a question?

Moved to the General Discussion area...

graham_mitchell

A supercharger would be my weapon of choice. It might be 20-30 hp down on peak power, but it should have much better low-mid range power and instant response, and higher reliability.

There must be a reason that dragracers use them over turbos

rickc

Superchargers have not really proven to be any more reliable in the real world than the turbos. Yeah, they are great off the line..but prove to be difficult to engineer into the Porsche engine bay with pulley restrictions, etc. Most of the big HP numbers seem to come from the turbo community and not superchargers. Since turbo lag is minimal with a well designed sytem, the differences off the line after staging are negligible. Most of the supercharger kits that I have researched, don't like high revs...better suited for American muscle at 4500 rpm.
Rick
'78 930

George 911-V8

Superchargers
PRO: Lots of different systems available to match nearly any budget and lust for power. They can produce significant midrange boost in addition to top end pull by the switch of a pulley.
CON: Requires crankshaft power to drive places a parasitic load on the engine. The need of a belt restricts blower placement.
Turbo
PRO: Powered by otherwise wasted energy from exhaust gasses. They make huge potential power gains. The boost level can be controlled electronically on the fly.
CON: Underhood heat can be a issue. The need to tap into both the intake and exhaust plumbing makes for a tough install more difficult than a supercharger. Overboost and possible engine damage only a stuck wastegate away and the lag from sizing the turbo for maximum power but the turbo is the nearest thing to getting something for nothing. I must say its a big question??? chose your weapon


George

rickc

Its very difficult to work out the pulley alignment for a supercharger application, and keep things like AC. There is just not any real flexibility there, unless you can relocate the crank pulley, or go with a custom serpentine belt arrangement. I am aware of a few kits, and you perhaps have more flexibilty with a Vortech type setup...but the manifold concerns and plumbing issues are not really any simpler than a turbo setup.You still need to feed the engine and give it air. I think you will find it easier to build higher more reliable horsepower with a turbo setup, since there is more room on the bottomside of the engine. As for heat, can't think of a much better commuter than a twin turbo 993 or 996. If someone has some pictures of a 500+ hp supercharger setup on an air cooled 3.3...I would love to see it.
Rick
'78 930

graham_mitchell

Rickc, ask and ye shall receive. How about twin superchargers?

George 911-V8

That is badddd is that going in a 911?


George

rickc

That's cool...what's it going in? Do you have specifics on this engine? What was the budget on that bad boy?
I hate to ask...where is the AC?
Rick
'78 930

graham_mitchell

I think it's safe to say that AC is not an option for this setup

The installation was by Enem of Sweden. I have no idea of the cost.

As superchargers don't have impeller spool up problems, it normally makes no sense to have a twin-compressor set up. However, this was built due to an intake restrictor rule in a particular series. They worked out that with two compressors they could make a lot more power and stay within the rules.

Besides, it looks amazing!

Lagavulin

Not when it comes to 928's it's not.

Currently, 'the king of the 928 hill' is ruled with an iron fist by centrifugal superchargers, and then the strokers. Of those who posted their dyno results, the order is:

Tim Murphy - 526 rwhp (Vortech)
myself - 492 rwhp (Vortech)
Marcus Hutchinson - 480 rwhp (Vortech)
Mark Anderson 470+ rwhp (Stroker)
The White Car - 449 rwhp (Stroker)

We'll see what's king of the hill after you post your dyno numbers.

Until then, the current numbers speak for themselves...

rickc

Well I guess you haven't been frequenting the turbo boards. Let's see them weigh in. The turbos are getting well in excess of 500hp. Go to http://www.imagineauto.com/ and expand your mind. Juan R are you out there?
Rick
'78 930

Lagavulin

The page does not work after the intro...

If you re-read my post, I'm referring to 928's, and I doubt there are any turbo 928's on the page you refer to.

Please don't get me wrong, I appreciate the power turbos make, thus have plenty of respect for them. On a 928 however, there just isn't any room for an efficient exhaust header to hang the turbo(s) onto. I'm sure you understand how instrumental the turbo exhaust system plays to minimize back-pressure to maximize available horsepower.

rickc

With the 928, I would investigate the Vortech type of Supercharger setup. They are used on numerous v8 setups and can make some crazy horsepower. With the v8 configuration your right......it's tough to hang a turbo and have it be efficient. I don't know what the deal is with the Imagine Auto website. Stephan Kaspar is the owner, and is also very active amongst the Rennlist community. Sorry for the confusion.
Rick
'78 930