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My bf was at work and emailed me this thought...

"yo...thinking about some stuff....your car (my auto 02 RS) has 9.5:1 compression ratio (meaning the piston compression) mine (5-spd WRX) is 8.0:1.
The thing is that companies lower the compression ratio so the car will be reliable with a turbo (meaning retail car companies). My car is actually losing horsepower with compression down and the gets it back when the turbo spools, hence no low end torque in the auto WRX. You are still in the range to put a turbo on the car. With your 4.11 gears in that thing, low end torque, and a chance to spool the turbo at the starting line, that car will really make a run in the quarter mile... even with a low boost setting.
(like 8 psi)..check 2.5RS.com and talk to people with turbo RS's...i think it will be worth it."

Anyone do this ? Anyone know if this is really possible or a good idea ??? Any info would be great, thanks.
 

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Yes, it is possible to turbocharge your 2002 2.5 RS. You will need to talk to some companies about getting a kit, such as Ludespeed.com, forcedairtechnologies.com, or vishnuperformance.com

Just remember, there is lots more to turbocharging your car than you think, and the reliability factor drops when you do add boost. Oh, and tell your boyfriend to get his info from credible sources. Your car is NOT 9.5:1, its 10.0:1.

The higher the compression, the less boost you will be able to run safely. Oh, and forget about 8 psi, you'll probably blow that thing in a month or two if its not tuned properly.

Do some more research and come back to us if you have any more questions.

Graham
 

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13 Years of RS
2005 Toyota Corolla :(
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5-6 PSI will put your power over a WRX, and your higher compression and larger displacement engine will give you better low-end power than the WRX. And since you have an auto, you won't have to worry about breaking you tranny with that power, either. Personally, I'm waiting for Templars supercharger kit to get finished, and to save up the money for it!
 

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5-6psi does sound like a good bet but, i would consider new valve springs. the stock ones are made for fuel conservation not power; meaning you'll get valve float or bust a spring a lot faster and tear up your heads. also, be conservative with the automatic. if you burn out your AWD system goes into a convulsion and turns your tranny into shyit. (mostly happens with AT's because they share control of the AWD so if one gets nasty so does the other)
not tryin' to be a jerk h8er, just informative
 

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zoinkssooby said:
5-6psi does sound like a good bet but, i would consider new valve springs. the stock ones are made for fuel conservation not power; meaning you'll get valve float or bust a spring a lot faster and tear up your heads. also, be conservative with the automatic. if you burn out your AWD system goes into a convulsion and turns your tranny into shyit. (mostly happens with AT's because they share control of the AWD so if one gets nasty so does the other)
not tryin' to be a jerk h8er, just informative
I used to run 12psi on stock springs, no float
Even had a 7,000RPM redline for a while, power died off because the heads were stock, but still no float (that was unboosted though)
With the auto, get a tranny cooler, and just dont neutral drop it (revving it in neutral and slamming into drive=BAD) and all should be fine.
 

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i agree entirely, however i speak in terms of longevity not about if it can hold out for a while. i know from my own personal experience that 3k for a little umph will work but, 3k that is unexpexted in repairs is a lot harder to come up with (and it does happen). either way is fine, just make sure you have what it takes to fix it if a problem comes up. were it me in your place i would definately concentrate on reliability first.
 

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Didn't someone came out with a supercharger kit for the EJ25?

IMHO, this is the best way to get more power for EJ25's high compression engine. I have just seen too many turbocharged 2.5s having all kinds of issues.
But don't get me wrong, turbocharging EJ25 is not mission impossible, just takes a lot of time, effort, and money!

and as for me, I went with EJ20 conversion route, and am very happy.

Cal
 

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the only s/c kit available for the ej25 i know of is from rimmer:barf: templar is working on a kit at the moment but, it won't be ready for at least a couple months. you can find info on that in another forum/thread(whatever you want to call it)
 

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13 Years of RS
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zoinkssooby said:
5-6psi does sound like a good bet but, i would consider new valve springs. the stock ones are made for fuel conservation not power; meaning you'll get valve float or bust a spring a lot faster and tear up your heads. also, be conservative with the automatic. if you burn out your AWD system goes into a convulsion and turns your tranny into shyit. (mostly happens with AT's because they share control of the AWD so if one gets nasty so does the other)
not tryin' to be a jerk h8er, just informative
No problem. Never heard that about the auto, good info to know. Thanks!
 
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