Hello all, I use to frequent the 2.0L discussion group often. I had a fairly modified WRX - suspension, brakes, chasis and a stage 4 dynoed at 284whp, starting at 192whp on same dyno http://home.earthlink.net/~warnern/ . Keep in mind I'm in california so my pump gas is a serious issue while tuning.

I had some questions if someone would be so kind.

1) Are there 3 cat's in the STi as well (up-pipe, downpipe, midpipe)?

2) What PSI is the stock STi turbo VF39? pushing out?

3) Without swapping out injectors and fuel pump how much psi can one achieve with the stock turbo and engine managment (or HP)? I'd like to get 350-380whp on 91 octane and not loose 2 cats. Is this going to require larger injectors? Willing to upgrade turbo, but I really dont want to adjust injectors and pump this time around. Bolt-ons and engine mangement? - possible?

4) The suspension on the STi is not what I expected. It's way too soft and there is way too much I'm not feeling. The car leans and sways way than I think is even reasonable for a car like this. Can anyone recommend a suspension setup that would be track worthy yet street driveable?

5) and lastly - where can I read up on the limited slip - what is actually going on as I move the slip to the rear or lock. Is there technical data I can read somewhere?

I would appreciate any info on the above..

My first impressions (while breaking in the engine - and thus keeping it below 4100rpms) is the car does have alot more low end grunt. But comparing power at this point is silly and thus I wont.

The suspension and brakes, however, are no where near as nice as the stop techs and RA STi setup I had. My old WRX was fairly neutral with slight under-steer.. The setup on the STi is soft, not terribly responsive and understeers quite alot. The brake feel on the brembos and over-all braking power is not nearly as nice as the stop-techs either. They also lack feedback, but the physical brake pedal feel is lack-luster compare to what I had. Obviously the pads I had were more agressive than that of the STi's stock units AND I had SO3's - and that combo (stop-techs and SO3 rubber (maybe steel lines?)) clearly had better stopping power and feel.

For people who track their STi's is there a common thought about brakes and where to go?

Nathan
my auto projects http://home.earthlink.net/~warnern/

1) only 2 cats. the uppipe is catless
2)around 14.5 psi (1.0 bar)
3)for that kind of power you need pump and injectors, not to mention turbo, EM, and a few other supporting mods.
4)a popular combo is the jdm pink springs and strut tops. other than that, you could go with a coilover that is damping adjustable. the teins can be adjusted from inside the car via an electronic control box. swaybars will help too.
5)I don't really know.

as far as brakes, the stock brembos are very good. swap in some goodridge ss lines and a decent pad like carbotechs or hawks and you will see an improvement.

My Comments are in bold.



1) Are there 3 cat's in the STi as well (up-pipe, downpipe, midpipe)?

2 Cats, no uppipe cat.

2) What PSI is the stock STi turbo VF39? pushing out?

14.5

3) Without swapping out injectors and fuel pump how much psi can one achieve with the stock turbo and engine managment (or HP)? I'd like to get 350-380whp on 91 octane and not loose 2 cats. Is this going to require larger injectors? Willing to upgrade turbo, but I really dont want to adjust injectors and pump this time around. Bolt-ons and engine mangement? - possible?

You really need new injectors because the IDC's are pretty maxed from the factory. The VF-39 has a tough time keeping 14.5 psi all the way to redline so a turbo swap is going to be very necessary. It is expensive to get that kind of HP out of the STi, but you will definately need to get a bigger turbo, injectors and remove the cats.

4) The suspension on the STi is not what I expected. It's way too soft and there is way too much I'm not feeling. The car leans and sways way than I think is even reasonable for a car like this. Can anyone recommend a suspension setup that would be track worthy yet street driveable?

I upgraded to a perrin rear sway bar and it made a noticable improvement. I like fast first and handling second so someone else please make some recommendations.

5) and lastly - where can I read up on the limited slip - what is actually going on as I move the slip to the rear or lock. Is there technical data I can read somewhere?

SEARCH

Why not get an Evo?

http://www.sti-buki.com/forums/showthread.php?s=&threadid=6


Best breakdown of DCCD workings I have seen yet.

Why not get an Evo?

Well I have driven one (Evo) at 80-90%. Ride is sharper, you do get more feedback, brakes do need to be upgraded for track use as fade is an issue according to an friend/track instructor who owns one. Car has less life too, which is both good and bad depending on driver.

Internals in both cars seems very strong. I want to believe that the extra displacement will make the STi easier to tune and have more low end grunt. I also dont trust mistsubishi as a company, they've gone through too much as of late. And lastly I can't stand the way it looks, it's simply ugly too me and the interior is aweful - simply aweful.. That is obviously opinion, AND I dont think the STi is a beautiful car either, but it's interior (especially that of the 05 as the 04 had some really ugly bits in it that have seemingly changed) is far nicer and the over-all car looks better to me. The wing has to go, think carbon fibre trunk painted is a must on either auto. I've yet to read how functional it is either.

nathan

Wow, those are some interesting observaitons/opinions you have there.

Evo brakes are slightly better and LESS prone to fade on teh track then the STi brakes even though they are essentially the same. I do, however, agree with your assessment of the interior of the car but, like I have always said, what are you doing looking at the inside of an evo or sti, look at the road fool! :p

I also wouldnt worry about mitsu too much, especially if you are modifying your car since the warranty will be void if you modify an sti or an evo. As fas as the external looks go, it may grow on you, especially if you get red :devil:

1) only 2 cats. the uppipe is catless
2)around 14.5 psi (1.0 bar)
3)for that kind of power you need pump and injectors, not to mention turbo, EM, and a few other supporting mods.
4)a popular combo is the jdm pink springs and strut tops. other than that, you could go with a coilover that is damping adjustable. the teins can be adjusted from inside the car via an electronic control box. swaybars will help too.
5)I don't really know.

as far as brakes, the stock brembos are very good. swap in some goodridge ss lines and a decent pad like carbotechs or hawks and you will see an improvement.

thank you appreciated.. I'll research the suspension and I fully intend to upgrade the pads and lines. I'm amazed that with 550 injectors you can't get much more than 1 bar of boost out the VF39. I assume the issue is not the turbo.

I also realize I said whp when I really meant crank hp.. 350hp to 380hp.. But regardless seems like you'd have to go with upgrading fuel to get that as well?


nathan

You should not have to upgrade anything in the fuel system to get 350 to 380 crank hp. Keep in mind that equates to probably around 300 whp, which is doable with stock turbo and fuel pump and injectors.

http://www.pdxtuning.com/images/dyno_plots/STi-s2-vs-stock.gif

That's with just the TBE and reflash.

You should not have to upgrade anything in the fuel system to get 350 to 380 crank hp. Keep in mind that equates to probably around 300 whp, which is doable with stock turbo and fuel pump and injectors.

http://www.pdxtuning.com/images/dyno_plots/STi-s2-vs-stock.gif

That's with just the TBE and reflash.

He wants 350-380 WHP

He wants 350-380 WHP

Then why did he say "I also realize I said whp when I really meant crank hp.. 350hp to 380hp.. But regardless seems like you'd have to go with upgrading fuel to get that as well?"?

Then why did he say "I also realize I said whp when I really meant crank hp.. 350hp to 380hp.. But regardless seems like you'd have to go with upgrading fuel to get that as well?"?

Yes I apologize.. I did orginally say WHP when I meant crank.. I really should have said "I would like another 40-65whp without modifying injectors/pump".. my bad.. no issues..

nathan