Twin Screw or Centrifugal

[m3f_mn-m3]

I have been doing alot of thinking about which supercharger would be better for me and I could use some opinions. Basically its between AA's rotrex centrifugal kit or the upcoming twin screw from Eurosport.



Here is the way I see it, the Eurosport puts out alot more power, 343 hp, vs the AA's 285hp, which is always good, but costs 7k for the kit, and the AA costs 5695 but they said they would throw in an exhaust, so that saves me another 500 since I would like to have one for either system. They say a new clutch is needed since the stock cant handle that much power, so thats another 1500 for a m5 clutch installed. So basically 9000 vs 5695. Another thing I like about the Eurosport is that its twin screw, and when I was talking to Josh over there he made a comment that made some sense, "no manufacturer uses centrifugal superchargers", and I cant think of any that do either. I also like that the euro has software by conforti.



The AA kit has been used for longer and I would feel less of a beta tester. It is centrifugal so it doesnt make such power right out of the gate like the twin screw, which seems like it would be harder on an engine. And is there such a thing as too much power?



I would be more than happy with either, and they both look to be about the same installation time. Im just having issues dedicating myself to either of them. If there is something else I should be considering please let me know. Thanks guys.

[m3f_96M3Power_4547fc3d60]

the twin screw supercharger should have a bypass valve that basically vents the compressed air at idle and cruising speeds. So there is no un needed pressure on the engine like a turbo at the same speeds. The centrifugal is making boost all the time, but less in the low end. The difference is that with the twin screw you can cruise at 100 mph with no boost, and the centrifugal you're starting to get into your boost range. And then on the twin screw when you hit the gas the valve closes with just about instant full boost. Your right though, its going to cost a good deal more to handle the power. Did AA say they'd throw in both the m5 clutch and the exhaust? Because 355 crank hp from aa is still going to need a clutch.

[m3f_mn-m3]

I didnt know about the bypass valve, it sounds like overall that twin screw is the way to go for reliability. I mean other than Im beta testing the thing since all of one has been tested so far. I have alot of trust for the conforti products, if it didnt have that name I dont think I would consider it. I thought the guy from AA said I wouldnt need a clutch so I emailed him again. If im gonna need a clutch for both of the kits, then the appeal for the twin screw gets even better.

[m3f_mn-m3]

A graph of eurosports dyno with AA's added on there for comparison.

[m3f_BMWGuy206_5da5c2e650]

I dont know if its fair to compare a mustang dyno result and a dyno jet.



All of the AA turbo M3s have high numbers on a dynojet than a mustang.



I made 328rwhp and 332ft.lbs torque to the wheel at 8.5psi. on 91 octane custom AA tuning on a dynojet. This is the Stage 1 OBD2 kit. On AAs mustang dyno I made 297rwhp and 310ft.lbs torque on 93 octane.



A customer of mine with the AA Stage 1 OBD2 kit made 356rwhp and 361ft.lbs torque at 9.5psi on a dyna pak. Reason he made more power is a custom straight pipe exhaust.



If you really want the twinscrew kit, save up and wait till summer.



BTW check out this website if you havent. www.boostjunky.com

[m3f_mn-m3]

I never knew that dyno's were different. So in theory, those numbers might be higher than expected on the eurosport site, which is interesting, then again whos to say which is right. Those HP numbers scare me as it is but good to know they might be closer. Im sure more numbers will come out in the next month as the twin screw is released.

What did you do about a clutch, Jon C? Did you upgrade it the same day or did you try to survive on the stock clutch. Im wondering if I do need a new clutch if I will be able to put it off for 5000 miles or something.

[m3f_BMWGuy206_5da5c2e650]

I never knew that dyno's were different. So in theory, those numbers might be higher than expected on the eurosport site, which is interesting, then again whos to say which is right. Those HP numbers scare me as it is but good to know they might be closer. Im sure more numbers will come out in the next month as the twin screw is released.

What did you do about a clutch, Jon C? Did you upgrade it the same day or did you try to survive on the stock clutch. Im wondering if I do need a new clutch if I will be able to put it off for 5000 miles or something.



I went with an AA High Performance Clutch kit and an AA Lighweight Flywheel.

I installed these items one month before I installed the turbo kit.



The stock clutch will not last for a couple thousand miles with either a Twinscrew or AA Stage 1 turbo kit under aggressive driving.