performance mods? (automatic)

[subaru-guru]

I have a 98 subaru legacy 2.5 gt thats automatic and i want to improve on horse power. i want to know of any mods that u recomend.

[Reason]

I would suggest taking a look in engine performance and maybe browse some members rides. A good base start of any performance area would be 2 qts of high performance blinker fluid.

[AJM]

And don't forget muffler ball bearings.


(seriously, get a light weight crank pulley.)

[SilentRacer]

Start by removing the intake silencers and getting a K&N air filter.

[Huffer]

Ditch as much additional weight as you can...

[Okin DaVanh]

...And keep up with this site as much as possible.



BtW- What are you trying to accomplish with your car?

DD, Time Attack, Drifter, 1/4 mile dragster, Top Fuel Funny Car??

[subaru-guru]

im going for all around performance and hope to reach at least 200 hp im at 165 hp. ive already installed a new exhaust system.

[ConnertheCat]

Hitting 200 is a very ambitious goal.

[Sarra]

Cams will be a must, EM, intake, and exhaust.

[Reason]

im going for all around performance and hope to reach at least 200 hp im at 165 hp. ive already installed a new exhaust system.

So you want 200 crank hp since you are at 165 chp NOT wheel horse power. 200chp should be easy. Full exhaust, intake, pullies tune. You could do cams but thats if you are looking for 200 whp.

[Perdue]

I'd speak with Delta Tuning about a Cam Regrind. I'd also look into an air intake (last dyno sheets I saw the ebay one made the most power), equal length headers, high flow cat and exhaust system, and a lightweight crank pulley. You'll then need some engine management to change your timing and fuel curves to match your motor's new needs.

Finding 200HP at the crank with cams and such isn't so hard to find. You won't find that at the wheels though, and you'll find even less with the automatic. Going any further NA is going to require a LOAD of work and an astounding amount of money (See: Subiesport Magazine Zero-to-Hero Project). You're better off putting the money towards a turbo kit or swap, the later being the most reliable option.

[subaru-guru]

im not gunna be able to do the swap and a turbo ive heard will mess with your trany. i plan on getting a ram air intake and locating it under the hood scoop

[subaru-guru]

what intake system do u recomend because i originaly had a custom intake system made but unfortunately it dit not fit corrrectly.

[Huffer]

guru has a lot to learn I see...

[Perdue]

I like the Cobb CAI, but it takes some modification to get it to work with the MAF system. There is also a warm air intake on ebay that supposedly makes more HP that the COBB CAI. Try searching "Intake" and "Impreza" or "2.5RS".

[subaru-guru]

yea ive only had a car for like a year and a half and trying to learn more about my car now that i have money

[decke48]

^^cobb made a cai for a maf 98-99 rs . but there hard to find

[subaru-guru]

how much more horse do u think the light weight pulley will add, because of the less mass for rotation, ive heard its not worth it.

[decke48]

it will give quicker revs. might gains some lost hp but not over 5bhp

[Huffer]

how much more horse do u think the light weight pulley will add, because of the less mass for rotation, ive heard its not worth it.

I have one on my BD. It's aight. I feel better knowing that the crank isn't having to turn as much mass. Been on there for 20k.

[03LegacyWgn]

ive notice a different in revs with my auto since installing the Group A crank and alt pulley.

all tho i have noticed a loss in TQ after adding the Warm air ebay intake.
better high end pull but off the line with the auto it lacks a bit.

[Wiscon_Mark]

Well, you have a 98 GT with a Mass Air Flow sensor - that location pretty much makes it impossible to run a ram air intake to the scoop. I would suggest just running one into the wheel well, it will pull plenty cold air there.

If you really want to make the car feel quick and sporty, doing so with an automatic transmission is both a poor base and a major restriction. I would honestly look at getting something else. But that's me, if you really want to stick with this car, I would do the following -

Full exhaust:
Equal Length Headers, High Flow Cat, Catback system (take your pick), all 2.25" piping

Cams, probably just a mild delta regrind

Port 'n Polish your heads

Minor supporting mods:
Lightweight Crank Pulley
Intake (Cold Air)

If you're really serious about Naturally Aspirated (non turbo) performance, you should think about EJ22 heads to up the compression ratio, and some sort of standalone tuning system as well.

[03LegacyWgn]

^^ are the EJ22 heads a direct bolt on?

[subba]

trust me, Get a 5spd, the 4eat isnt worth it, take it from me i tried with it, i swapped my tranny and the 2 things i notice is that the car feels lighter and the throttle is more responsive.

[03LegacyWgn]

^^ what was involved in the swap process?

[subba]

I had everything on a silver platter for me so it was very painless but their are a zillion threads on the swap section for more info.

[03LegacyWgn]

lol how does one get this said silver platter

[Perdue]

You're Canadian. Canadians can't have silver platters! :lol:

Seriously though, the swap is pretty straight forward with very little wiring. Look in the swaps section.

[subba]

I own 2 Legacies lol 1 is automatic and 1 is manual, so i had everything i needed for the swap, only thing i had to pay besides the labor was to get the TAch and Rev Lights working.


BTW upgrade the grounding because it makes the 4eat shift a lil quicker...not WRC type fast but fast.

[03LegacyWgn]

oh cool thanks ill give that a try, also doesn anyone know if the ecu controlls the shift points or is there an ecu for the tranny?

[03LegacyWgn]

You're Canadian. Canadians can't have silver platters! :lol:

Seriously though, the swap is pretty straight forward with very little wiring. Look in the swaps section.

yea we do..... we dont have GWB


lol suckers