if power is proportional to boost , and if natural pressure is 14.7 then total boost is 14.7 + SC or turbo boost, the gain in power is proportional ideally and the factor is (Total boost=14.7 + added boost)/ 14.7 . This is ideal , in reality it is a bit less especially at very high boost (since other factors come into play). Turbo is closer to ideal than SC.
AS far as my car is concerned , theoratically the gain must be in the 20's but it felt more that is why i said 20-30, i cannot tell how much boost i added because it is very hard to know, because although it seems that i have 1.2 psi more as a peak on redline, however, it seems that boost increased more at low rpm . let us say at 3500 it was 4psi (for example) now it is 5.5 , but maximum boost was 7, now 8.2 . In short , it seems the power difference is bigger in the lower rpm range rather than peak power.

 

We need to be careful here when talking about a supercharger making more heat compared to a turbocharger. What kind of supercharger are we talking about? The compressor section of a turborcharger is the _same_ as the compressor section of centrifugal supercharger. An an exhaust turbine intake impeller transfers heat to the intake charge, unlike a belt driven centrifugal blower, so that a belt driven centrifugal blower has the _highest_ adiabatic efficiency in general use.

 

About HKS SC, you can increase your power to 500+ by:

1. Change the BOV to allow higher boost (not pulley. it won't help).
2. HKS Pro V (so you can have someone tune it.)
3. Bigger injector, built motor, etc...

But HKS Japan already stopped supplying SC unit. The new SC unit, also rotrex style, will be out in Q4.

 

I didn't say SCs create more heat than Turbo, to the contrary. What I was saying was that the optimum power gain possibly was 7% / 1 psi, but that since there is a heat transfer that 7% was nearly impossible to attain.

Danny

 

The HKS SC thats is in the USA...will not make over 350whp...even with Pro-V - smaller pulley - or as much money as you can throw at it . Its been tried

 

For HKS SC to make more boost you need to change the BOV not the pulley. HKS SC spool up much faster than other SC so smaller pulley don't make any difference. It is the BOV that limits the boost level.

 

I am not too sure about that man! Your buddy, NINJA-Z has the HKS and put down mid 330s with just the Nismo cams, Nismo exhaust and the HKS Navigator. He is talking of going to AAM and having them install headers, a larger intercooler, a smaller pulley and something else which I cant remember. From what I have heard, Mike@AAM says he should be in the 370-380RWHP range. ANyway, I have just heard this from him so I have not actually heard it straight from Mike yet! I definitely think this is doable. Just my opinion.

 

Probably true, but so what? Add up the #'s

HKS Blower 5-6g's
bigger pulleys, bov

And only a net gain of say 380 at the wheels? HKS is a great company but that's a crappy and expensive way to blow some bucks for boost. A vortec kit with pulleys can easily make 450 at the wheels with proper tune. HKS should stick with turbo's. Through my ordeal with my blower buildup project I had to admit that Vortec has a more reliable belt system. The procharger actually flexes forward during high rpm (thanks to CP Racing for diagnositics) and something needs to be done to brace the blower because the cog belts breaks easily if it skips a tooth. With a Vortec it may slip a little at times but atleast it won't explose like the procharger unit will.

Any supercharged Z with 450 at the wheels is respectably fast. One positive aspect of supercharging versus turbo is that's it's easier to spay nos (wet setup) because there is not a huge surge in tq like there is with a turbo which results in less head lift. My 50 shot worked out to exactly 100 on the dyno and it's makes the car very fast.

 

the only thing i can say is for someone to post hks dyno vs vortech dyno and look at the power curves. Although hks has less power the power curve is more useable. Also hks does not have that rattle can sound that most vortech and prochargers have some like the sound and me personally hate it. bout no dought that vortech is a nice kit just a few draw backs.

 

Every kit has draw backs....The HKS SC draw backs ARE ?????

huge price
only tunable by a F-con Pro dealer.....how many dealer are there ?
Very small IC
upgrades for more hp ??/???

I would choose a HKS over the Stillen any day . If I knew I would be satisfied with a 50 to 60 whp gain over stock . With just pulleys and a retune . You can gain a 100whp more than the 80whp gain from the stock Vortech .Thats getting near doubling the whp of a stock car . I say...you get way more for your money with the Vortech or the ATI . Than the Stillen and the HKS SC's

 

^ Thats true and i see what your saying, but if you wanted alot of power. What i dont understand is with a built motor why didnt you just go turbo? You could make much more power with out worring about pullies. Most people that get F.I are happy for a little and then want more which ends up being a big headache with other problems. But oh well thats all i got to say about this topic. i had a turbo car and kept making more and more problems it was nice on the outside but after building the motor and all that other stuff it took alot of the fun out of it and i just wish i stay with the little greddy kit when i was the happy and problem free.

 

If you want big power go turbo, but there is something cool about a high output supercharger Z. Instant power, no lag. Super fun for drifting without waiting for any spooling. Plus not many people have done it so it's a challenge as well