Rx7TyreBurna

iTrader: (1)

Well, I was wondering if anyone on here has experience with a ProCharger supercharger. I am going to start saving $3k for next summer. I spent my $2k for this summer already, so next summer, I am planning on getting a microtech and a supercharger.

I don't really want to go turbo. I know there are lots of them. Though, I haven't decided yet.

I was wondering if 300-350 HP is reasonable with a procharger and a microtech with some aggressive street porting.

Thanks.

anewconvert

iTrader: (1)

I just dont understnad the choice of a Procharger, or any centrifugal supercharger.

You are in a car with little low end torque. and then you are choosing a S/C where you will only see full boost at redline. Im sure it will be fast, but even with a greater peak hp a roots blower or twin screw would be faster.

To each his own I guess. The F-body guys have been using them for years. Good choice of S/C if you are insistant on going centrifugal.

BC

Rx7TyreBurna

iTrader: (1)

I have been considering other superchargers, but I like the centrifugal ones. A small advantage I see is that I will be able to go with a true dual exhaust system and not have anything like a turbine in the way of the exhaust.

I know that I will still lose some power through drag on the belt, but I am hoping that the supercharger will be slightly more reliable then a turbo.

I would like to get a centrifugal SC that sees a good amount of boost down low.

Roots you said? Any manufacturer that would be a good choice?

I am looking for a maximum of 350 at the wheels. I would like around 300.

Eh, still researching a lot of stuff. I would really like to stay all motor, but I don't think there are any cheap 20B motors out there that are all N/A and I could mess with for around $3k.....

So, SC seems reasonably, though, I may still end up going turbo...

Also, with the SC, I wanted to run a really small IC so that it can't really be seen. I love the stock look of the RX-7. Very sleek. I just want more power.... N/A != Power....

Evil Aviator

I think that maybe you don't understand how a centrifugal supercharger works. It is belt driven off the engine at a ratio that yields max boost at or near redline. That means zero boost at idle, a few pounds of boost at 2000 rpm, a few more pounds of boost at 4000 rpm, a few more at 6000 rpm, etc., until max boost at redline. Therefore, a centrifugal supercharger has little to no boost down low. This can be an advantage or a disadvantage, depending on the application. By your stated personal preference, this would be very bad.

The supercharger is usually slightly less reliable than a turbo due to the complex drive mechanism and the very fussy weak link known as the belt. A typical turbocharger only has 1 primary moving part, and maybe a couple more if you count ball-bearings and the wastegate components. If you think about it, how many times have you seen anybody on this forum complaining about their stock turbo failing, despite that fact that it is at least 15 years old? Now compare that with how many people on this forum have a supercharged RX-7 that works properly and performs significantly better than a stock TII.

In that case you can eliminate the Roots (Eaton) supercharger from your list of choices.

Rx7TyreBurna

iTrader: (1)

Thanks. I didn't think a CF SC would be able to give good boost low. I knew that it was belt driven, but was hoping there was something I missed.

I am probably just going to keep saving money until I figure something out. maybe I will just buy a new car.

Thanks!

anewconvert

iTrader: (1)

There are plenty of companies that make A/W IC for roots blowers. www.zzperformance.com is one. Their IC are built for M90's though. There are other options available. One being to place the blower upside down on the engine, or on the spark plug side of the engine, and use a blower from Jackson Racing (MP62 is the SMALLEST you would want to go) and route the cahrge to a front mount or an A/W IC.


Roots blowers do not mean you cant use an intercooler. Mercedes, GM and Ford are three major manufacturers off the top of my head that use IC'd roots blower on their cars.

That being said water or alcohol injection can accomplish nearly the same intake temps (to a point) as an intercooler, and there are water injection companies all over the place.

www.camdensuperchargers.com builds a RX7 specific roots blower and manifold. Its not cheap, since everything is new, but if you were going to S/C a rotary that would be the best route imo. The centrifugal blower is not the best route.

BC

Evil Aviator

Modern ball-bearing turbochargers have very little lag at low and mid-range boost levels, and they offer far better efficiency and higher boost potential than a Roots blower. Even the 1980's vintage stock TII turbos have very little lag when run at their design boost level, which is pretty much the same as the Roots blower design boost level of 6-8psi.

Yes, but trying to use a small ALIC in conjunction with a Roots blower in an attempt to make 300-350whp on a stock-ported 13B is an effort in futility. Also, as you stated, an ALIC is not very cheap, and most of the people on this forum are broke and tend to favor corroded junkyard air-air intercoolers over new models.

It's a good route if your performance goals do not dictate a lot of boost at lower engine rpm's. I have seen centrifugal supercharged RX-7's perform very well in autocross events. I do agree that it is not the best route for Rx7TyreBurna based on the stated performance goals.

BTW, a centrifugal supercharger is not a blower.