Supercharging: the forgotten form of FI

[Dimman]

Serialk11r:

Old 4AGZE in the supercharged MR2 used an electromagnetic clutch to de-couple the blower at idle or low load or something...

[Matador]

Originally Posted by Dimman

Serialk11r:

Old 4AGZE in the supercharged MR2 used an electromagnetic clutch to de-couple the blower at idle or low load or something...

That it does. However, they used a roots type blower.

[Dimman]

Originally Posted by MatadorRacing_F1

That it does. However, they used a roots type blower.

Could work with a Lysholm style, too.

[serialk11r]

Wouldn't that require a bypass valve? In that case they can just open the bypass, the extra air goes back out, no energy spent.

[Matador]

Originally Posted by Dimman

Could work with a Lysholm style, too.

No doubt. Don't dispute that at all. In fact, I wonder why Rotrex hasn't tried to implement that. Have they?

Originally Posted by serialk11r

Wouldn't that require a bypass valve? In that case they can just open the bypass, the extra air goes back out, no energy spent.

.... Bypass valve for what? Maybe I'm missing something?

The way the clutch works is that there is a coil and a plate. plate attached to the screw of the charger, coil in the pulley. When manifold vaccum drops below a programmed threshold amount, coil is energized, plate mated to pulley and surpercharger is engaged. Otherwise it doesn't blow. That's basically all there is to it.

[ichitaka05]

'09 post I made

Originally Posted by ichitaka05

Some ppl are doin' SC on their Impreza. IIRC Raptor made NA Impreza SC kit for it too. Raptor SC kit

As for Root blower, are you talkin' bout this?

.

plus here's the concept H4 SC

[madfast]

Originally Posted by Dimman

Positive displacement SC's are great for an upgraded DD situation, but they are usually limited to how much boost you can make efficiently.

I know a guy with a positive displacement kit on his Miata but no IC (integrated blower/manifold), and when he changed the pulley to get 10 (or 12, I don't remember) psi he needed water/meth to keep it from pinging.

He's making about 200 whp now though, and it sounds awesome. But if he wanted more power, he would be going turbo.

yes but the miata is a car that needs the responsiveness of a SC. consequently, turbo kits arent as popular as SC kits, on the NC miatas at least. also being that its such a small, light car. it need not have 400 hp. a 200 whp miata isnt the fastest thing on 4 wheels, but its no joke and i bet a ton of fun. sometimes less is more, when its done the right way...

the FT i've always thought of as a 2+2 coupe version of the miata. and likewise, it would do better with a SC and its responsiveness, its low end tq, its flat tq curve. and also likewise, it need not have huge power to be fast. and looking forward, the NC miata SC made 253 hp. the FT has D4-S that the miata doesnt have. also that kit only uses a 4th gen eaton unit. a TVS 6th gen eaton would again be better. so a 300 hp FT with a flat tq curve? that's not unrealistic... sign me up!!!

[serialk11r]

Originally Posted by MatadorRacing_F1

No doubt. Don't dispute that at all. In fact, I wonder why Rotrex hasn't tried to implement that. Have they?



.... Bypass valve for what? Maybe I'm missing something?

The way the clutch works is that there is a coil and a plate. plate attached to the screw of the charger, coil in the pulley. When manifold vaccum drops below a programmed threshold amount, coil is energized, plate mated to pulley and surpercharger is engaged. Otherwise it doesn't blow. That's basically all there is to it.

So with the pump disengaged, the engine has to pull air through the pump...I have a feeling that doesn't really work with a positive displacement pump. Thus, a bypass valve so the engine doesn't pull air through the pump.

[Dimman]

Originally Posted by serialk11r

So with the pump disengaged, the engine has to pull air through the pump...I have a feeling that doesn't really work with a positive displacement pump. Thus, a bypass valve so the engine doesn't pull air through the pump.

Correct. It has one.

http://mr2.com/TEXT/SuperChargerInfo.html

[Type[R]+]

The only problem with tvs/roots I can see is intercooling. Seems like a PITA to do it, where as with centrifugal, just whack in a air-water intercooler inline and away you go.

[madfast]

both roots and lysholm have bypass valves for part throttle and idle/cruise...

Originally Posted by Type[R]+

The only problem with tvs/roots I can see is intercooling. Seems like a PITA to do it, where as with centrifugal, just whack in a air-water intercooler inline and away you go.

built in water to air intercooler FTW!!!


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[Type[R]+]

looks like a good little set up there madfast. Is that production engine or aftermarket kit?

[Ryephile]

^^That's the GM LSJ engine, which uses an Eaton M62 and a W/A IC.

Supercharging is still my preferred choice of FI solely due to their proportional torque output vs. the Go pedal....aka the drivability is closest to naturally aspirated. TVS and twin-screw [various brands] are the most efficient currently available, however good ole Roots are better than nothing.

Forgotten it is most definitely not.

For the numbers queens, supercharging is still king; find me a passenger-car piston engine that makes more power than an NHRA Top Fuel dragster.


I'm totally fine with the FR-S being N/A, however if TRD wants to make a Warranteed supercharger kit I just might be interested.

[Random_Art]

Originally Posted by Ryephile

^^That's the GM LSJ engine, which uses an Eaton M62 and a W/A IC.

Supercharging is still my preferred choice of FI solely due to their proportional torque output vs. the Go pedal....aka the drivability is closest to naturally aspirated. TVS and twin-screw [various brands] are the most efficient currently available, however good ole Roots are better than nothing.

Forgotten it is most definitely not.

For the numbers queens, supercharging is still king; find me a passenger-car piston engine that makes more power than an NHRA Top Fuel dragster.


I'm totally fine with the FR-S being N/A, however if TRD wants to make a Warranteed supercharger kit I just might be interested.

This seems like an unfair comparison. Top fuel dragsters have engines that are essentially bored out blocks of iron, monster pistons, and no cooling. They also run off Nitromethane as opposed to gasoline or ethanol. You'd never see a factory engine come in a Supra with that kind of set up since they would be exploding left and right.

Though, I can see why a supercharger would be ideal for the drag strip. The instant throttle response would decimate a vehicle suffering turbo lag off the line.