How do we get someone to develop a supercharger that will give torque across the rpm band? We need a Roots type blower!!

 

Al- I think that we are going to have a hard time finding someone to do a roots style supercharger for the S2000. I believe that are only hope is that someone will develop a kit based on the whipple style(roots) supercharger. I am pretty sure that Jackson Racing has an exclusive contract with Eaton & Magnusson for that type of supercharger. About a year ago I was going to attempt to devlop a kit for the s2000 using an Eaton blower. Although, Magnusson said they would sell me a blower for development , they also stated that I could only buy one ever because of the aforementioned contract. The price of an eaton blower by itself is much less than most people would believe. ( about 800 dollars if I remember correctly.

 

I beleive one is in the works but not sure when its going to be out, its already overdue.

BTW is not Jackson's I think they put theirs off for awhile.

 

im interested in a sc that would add low end too... i juss got vol. 46 of hyperRev magazine from japan and i noticed that some of the s2ks featured in it had a eaton type sc in them? does anyone know what kind of sc they use in japan?

 

I'm curious what you guys expect out of a "low end torque" blower.

From what I've learned of superchargers, they can only magnify the characteristics of the engine, not alter them. This is appearantly due to the belt-driven design. From what I understand, a turbo has a better chance of altering the characteristics of the S2000 than a supercharger ever will.

Wesmaster

 

Wes, it is not entirely accurate that superchargers magnify characteristics of the engine.

Yes the comptech one does, simply b/c it doesnt spool up till 5-6k rpm or whatever (pls don't flame me, just a figure higher than 1-2k ok!!) - hence it doesnt actually boost untill higher rpms, resulting in the power at the top end being magnified.

The ideal supercharger/turbocharger would be one that simply lifted the whole torque curve vertically, such that you get the same proportional increase across the whole rpm band. The JR supercharger for the teg gsr comes very close to doing this.

I will stress again, that you dont really want a supercharger that puts a big lump in the bottom end, b/c you will lose linearity and throttle response. What we want is a linear increase throughout.

I have not seen any dyno plots for the JDM DinstoBeliiza roots charger - but the website quotes 300ps - I think at the flywheel since they have the stock quote at 250ps on the same page.

 

I think a turbo charger has the best chance of adding low end torque based on the fact that a turbo causes back pressure at low rpm's which causes low end torque. I don't think changing the characteristics of the engine wouldn't be bad as long as torque was raised across the band. I am waiting to see the dyno charts from derrcky. I think they will show some interesting results.

 

elanderholm- Backpressure is NEVER beneficial to performance, what you are talking about is delta pressure.

Backpressure: Resistance to air flow; usually stated in inches H2O or PSI.
Delta Pressure(aka delta P): Describes the pressure drop through a component and is the difference in pressure between two points (inlet and outlet for a given exhaust section).

Pressure varies inversely with velocity, so high delta P values indicate the exhaust gasses are accelerating rapidly from the exhaust valve area to the collector (or wherever your measurement points are. Good exahust velocity is extremely important to cylinder scavenging and anit-reversion properties, which is why a good delta P value enhances power output. Generally speaking, large volume exhaust have good delta P only at high flow rates, which is why they work well at high RPM and often times poorly at low RPM. The right size exhaust is (among other things) the best compromise between high pressure drop at low to moderate RPM, and high flow rates at high RPM.


tze- Even roots and Lysholm superchargers must spool up to a certain degree before they can maintain maximum desired pressure ratios, which is why you won't usually see maximum boost fom them until around 3000 RPM. The big difference of course is that's a damn site better than a centrifugal compressor which is crank driven (ala the Comptech design).

 

Yep Texan - the thing is that the roots blowers do spool very quickly though - I do think that the teg one is spooled up by 2k from what i have seen.

BTW texan if you are bored pls go to Clubrsx.com and kick some a$$ on the "performance" forum, there is a discussion there about cat-backs etc and backpressure, and unfortunately a few dolts have got it in their head that backpressure is the beesknees and is essential for NA perf. argh

I just can't be bothered arguing w them anymore