Fluid Dynamics

Lol, that's a drawthrough carb camden roots setup, which is totally inferior to a throttled, intercooled twin screw and efi setup. They look similar, but there are three types of superchargers and various brands of each. What is pictured there is one of the least efficient brands of the least efficient type of superchargers, and no intercooler. Of course they are winning with a turbosupercharger compared to that thing. I'll bet the turbo setup has intercooling, and it's basically the same as the as an exhaust driven centrifugal supercharger, which blows a roots blower out of the water for efficiency.



Intake temps would be above 200 at about 7 psi for what's in ur picture. Hot air does not = power. A twin screw with intercooling has the benefits of high boost efficiency (charge density, meaning low intake temps for a given psi) but with instant boost availability and a brick shaped boost profile - full boost available very low in the power band. It's like getting the best of turbo with the best of supercharging: high boost efficiency and high boost capability with instant throttle response and full boost arriving early in the power band. Not to mention no restriction in the exhaust system . .

l8t apex

Just questioning your thoughts: if so even when Paxton came out with its blower for the FC it didnt fly. why? My guess, cause I dont know, but I did have one in hand, was due to the limited boost and the parasitic drag it take to use them. With an I.C. how much boost can a blower made for rotary make?Then how much HP is used to turn a big one/geared blower?I think it would be awsome to have one that wold produce awsome numbers.

That pic was from Rotary Performance (Garland, TX )around 1994.

Jeff20B

Whipple Chargers are so cool! I know a guy puting one on a 20B.

Fluid Dynamics

The paxton centrifugal kit had no intercooling and ran 7ish psi. I've seen a few web sites with stock port FC NA's using the paxton kit and mild exhaust mods (header and highflow cat) dynoing 220-230 rwhp. Again, their intake temps were high, a few tens of degrees lower than 200 which is hot if you ask me. Plumbing a paxton supercharger like a normal turbo with fmic and even water injection + a little more timing advance would show a substantial improvement in the rwhp for the same boost psi.



As for my little pipe dream, I'll be trying to get my hands on a Millenia twin screw lysholm oem supercharger. It is similar to the whipple and almost as efficient, and substantially better than a comparable roots. The Millenia S engine is 2.3l and makes 200 hp at 5500 rpm. It makes 210+ foot pounds of torque at roughly 3500 rpm. It would be proper to use a Mazda twin screw compressor on a Mazda rotary engine.