I am seriously not trying to be patronizing, but have you ever felt turbo lag?

I have a turbo that is quite a bit larger than stock and the lag is negligible. I'd recommend that you go drive a WRX; one that hasn't been modified and one that has (bigger turbo.)

Some folks even barely upgrade their turbos, because they're looking for low-mid power/tq. On those cars, you wouldn't even know that they have forced induction.

 

You may find that there is too much lag and it isn't to your liking, but I'd bet not. A stock WRX zooms up the rpms fairly quickly.

 

Search for supercharger and you'll find many threads about this. What you will find is that no one makes a bolt-on kit just yet, and the amount of work and plumbing it would take is tremendous and few shops would know how to do it.

There is an interesting thread on another forum (where escapes me, sorry) about someone adapting a Mercedes supercharger (from a Kompressor engine) to either a 2.0 or 2.5 N/A Subaru block; I'll post it if I find it, but his results were NOT impressive for the amount of work that was done.

EDIT: Here is that thread: http://forums.nasioc.com/forums/showthread.php?t=605625

 

I am the one who did the mercedes m62 blower.

Actually, the results are pretty impressive finally but not awesome. Yet. I am running 7 psi on average (about 200-225 chp. Stock is 130 chp). I need to spend another $300 or so on a new crank pulley and I should have a minimum 250 chp, possibly up to 300.

I have done all the work and research so it is fairly easy to follow what I have done. However, this is on an older legacy and may not translate over as easily to the RS.

There are two kits in progress currently. One is being done in Colorado and one in Australia. These are both for the RS and use centrifical superchargers. They will be good to start with at 5-6 psi, and they plan to be able to boost up into the teens.

The lack of turbo lag is a great feeling, but it is really only noticable when you get the boost over 6 psi.

There are also some old Rimmer kits floating around but they are very rare (maybe 20 max to start with?).

The cost to supercharge my wagon (1990 2.2 legacy) started at about $800 for 3-4 psi of boost. As soon as I wanted more, the cost tripled basically because the fuel system had to be upgraded, custom pulley and intakes and I needed an intercooler.

But it is possible and the results can be amazing. If I wanted to, is would be possible to get the boost close to 20 via the supercharger but I would have to upgrade to a turbo block most likely and spend even more on new fuel injectors, an m90 supercharger, and a standalone management system. But then I would be pushing incredible instant power that would brake my drivetrain!

 

^^^

Good read.

 

The Aussies have 3 NA SC kits but I can't find the link.

 

yeah im only looking for 5-7 psi so i think ill go shopping for a Kompressor blower!.
Turbo lag is not that bad when you only want a fiew psi, smaller turbo smaller boos smaller turbo leg.
You can cut down on it by porting it correctly.
I personaly like to play around with controled slides (trying to learn to drift correctly), so for me it would alot easier if i had instent power.

 

Turbo lag is not the same beast on a naturally aspirated and then turboed car. First, you have na power like you always did, and then the boost doesn't hit as hard since you can't run so much of the stuff, due to your cr. The wrx has less displacement and lower cr than a 2.5, so it's worse off boost and better on.

That said, the 2.5 really isn't a happy motor for forced induction due to its design, and no, you don't have the same engine as the sti, it's not even close. Best bet is to swap that puppy out and get a turbo motor.

 

That's an interesting looking S/C. Almost like a turbo. Definately not what we're used to seeing on domestic cars.

http://www.hotkey.net.au/~shatteredf...ct/engine2.jpg