Turbo Kits: Rational boost threshold yet?

[OrbitalEllipses]

Originally Posted by arghx7

Basically, OP is looking for Subaru to offer the new turbo 2.0 liter engine in this car

With a standard transmission and higher redline...we'll likely see it in the next WRX.

[Exhaust]

Ok I know this is was already vaguely posted above, but why not go with a supercharger for that wide torque window your looking for? Is the amount of HP your getting in the SC versus the FI the problem?

[HighLife]

Maybe one day a sequential twin turbo could be fitted.

[Tansey86]

Originally Posted by HighLife

Maybe one day a sequential twin turbo could be fitted.

4 cylinders are better suited for 1 turbo not 2. I don't inderstand people's obsession with power under 3k. I want traction and decent mileage under 3k

[frsvr4]

Originally Posted by Tansey86

4 cylinders are better suited for 1 turbo not 2.

Inline 4 cylinders, sure.

[Supermassive]

Originally Posted by AdamVR4

Inline 4 cylinders, sure.

The problem you run into is that if you go with a twin setup you only have 2 cylinders spinning a turbo, in effect you have 1 liter of displacement per turbo. It's not ideal, but a turbo feeding a supercharger could be interesting...

Another thing to consider is where the hell would you cram a dual turbo setup in this car...dunno if you've looked under the car but theres not much room under there for getting too crazy with the turbo setups.

[Ryephile]

Originally Posted by arghx7

Basically, OP is looking for Subaru to offer the new turbo 2.0 liter engine in this car

As always, @arghx7 hits a home run again. That engine would indeed fit this car very well.

[stockysnail]

Originally Posted by Ryephile

If I were looking for a supercharger setup, I'd want a TVS as it has excellent adiabatic efficiency and doesn't lose fuel economy versus a twin-screw, but nobody's developed one yet for this car. Nevertheless, that doesn't address my question of a low/mid RPM turbo kit. I understand big peak HP numbers impress, but I'm not looking for that. If anyone has driven a current BMW 328i, Cadillac ATS 2.0T, or VW Golf R, those are reasonable examples of the torque curve I'm interested in.

TVS supercharger for the win! Seems only Lotus guys know about the TVS. Someone slap one in the FA20!

[Ryephile]

Originally Posted by stockysnail

TVS supercharger for the win! Seems only Lotus guys know about the TVS. Someone slap one in the FA20!

It's rather surprising how ignorant most aftermarket tuners are of the TVS's unrivaled qualities. Not to totally derail the thread, but personally I feel this would be a fantastic solution for the FA20. TVS's overall efficiency is excellent and they're still an air pusher, so there's no inherent significant parasitic drag from internal compression like a twin-screw or centrifugal. They're really the best overall solution for a supercharged setup, but they're also the most expensive.

That said, a good small turbo setup would give a big flat torque shelf while offering the best fuel economy. You can't have everything; a small turbo setup would trade throttle response and a little bit of lag for better FE and more torque in a less-expensive package over a TVS setup. For most enthusiasts that can't swing a $8k TVS setup, a $4k small turbo solution that gets great fuel economy and is super fun on twisty back roads is hugely attractive.

So, to get back to the topic, any turbo kit companies out there willing to belly up to the table and offer a small turbo kit? The marketing prowess of "balanced power" seems like rather low hanging fruit for a car that's promoted so rigorously on being a balanced chassis.

[arghx7]

Small turbo kits are vulnerable to the "look at how the power drops off" criticism, from a marketing perspective.

[OrbitalEllipses]

Originally Posted by arghx7

Small turbo kits are vulnerable to the "look at how the power drops off" criticism, from a marketing perspective.

Transient response outweighs any criticism of too little top end.

Many people will end up with too large turbos and realize that while they make 400+ peak who their car sucks to drive anywhere except the track (or unsafe highway pulls). A large portion of the STI crowd is like that: GTX35 turbos and gobs of power...above 5K rpm.

[Ryephile]

Originally Posted by OrbitalEllipses

.... A large portion of the STI crowd is like that: GTX35 turbos and gobs of power...above 5K rpm.

This is exactly what I'm trying to avoid. My proposal is for the experienced enthusiast that is beyond "My First Turbo Kit" and require a total package that is responsive and a good companion for a twisty back road romp.

Originally Posted by arghx7

Small turbo kits are vulnerable to the "look at how the power drops off" criticism, from a marketing perspective.

We both know that's not relevant for the demographic I'm talking about. You also know the only reasons the power can taper is because you're running the compressor off the map or the engines' VE isn't meant for high RPM operation. The FA20, seeing that ECU tweaking yields almost no power gains up top, implies the VE falls off sharply over 6500. The turbo should be sized according to this approximate VE fall-off. I see no reason to waste compressor bandwidth band-aiding the engine's VE curve. I know this is a bummer for those that cherish the wishful-thinking high-revving nature of this engine, but the data speaks for itself.

[OrbitalEllipses]

Subarus typically have poor VE...

[hooman]

2 cylinder spinning turbo is correct