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USDM MY04 STi - Platinum Silver
ITERATION #1 - Suspension Cusco titanium front strut bar
Cusco carbon fiber rear strut bar
Cusco rear strut bar triangle brace
Cusco aluminum “H” lower arm brace
Hotchkis Competition sway bar kit
-25.4 mm hollow front / rear sway bars
-Brackets
-Bushings
-Endlinks
Whiteline steering rack bushings
Prodrive STi springs
Recently, I read an excellent turbo package review by Flycaster. It was very informative for me and so I decided to review the parts I've used on my car for the community.
**DISCLAIMER**
Let me just start off by saying I'm posting my upgrade path with the car so people can ask me to review any part listed if they are curious or want more information than what has been provided. I would have loved to see this type of information while I was doing my pre-purchase research. If you have read reviews of the parts I'm using before please bear with me. Much of the information regarding parts is contained in my original posts. If you want more info, just ask and I'll provide my opinion on the parts I have used or am using. The stuff posted is just my experience with the parts used. I'm in no way trying to say any part is bad, just that some parts didn't meet my personal needs/preferences.
The very first modification I purchased for the STi were the Cusco titanium front strut bar, Cusco carbon fiber rear strut bar, and the Cusco aluminum lower arm “H” brace. These modifications made a slightly noticeable difference in sharp cornering maneuvers.
Wanting more performance, I decided to buy the Hotchkis competition swaybar package for the STi. Parts included are listed. I must say, this is the most worthy suspension modification I’ve done to the car. Not that the other things I’ve done are bad, just that this swaybar package is so dang good. I leave the rear bar in the middle/neutral setting pretty much all the time. I must say, the car is so stiff now that there is basically no sway whatsoever. That stock understeer is totally gone. The car is the most neutral handling, forgiving car I have ever driven. No comparison. Only complaint about this package is the endlinks constantly come just a hair loose. They have been tightened 4 times and still come loose after 2-3 months of driving. They won’t come off, they are just slightly loose causing a little noise. I’m used to it and don’t even notice anymore, but my wife does notice. I’m planning on swapping in some Whiteline endlinks to try to cure the noise.
After the good experience with the swaybar package, I decided to upgrade the springs with Prodrive STi springs and to upgrade the steering rack bushings while I was at it. The springs are great and I love them. They have a slightly more “raked” appearance than the STi Pink springs. Bushings made a slightly noticeable difference in turning. The wheel response is immediate now instead of before when it was a little “vague”. Both were worth while mods. The Whiteline steering rack bushings are a great cheap mod for the USDM MY04 STi. Only $30 and makes a positive difference you can feel.
The only other thing I’ve done to the suspension is the triangle brace for the rear strut bar. Honestly, I haven’t noticed much difference with this mod, but I haven’t been to an autocross since so maybe I just haven’t cornered hard enough to tell. It definitely looks great in my stripped out trunk compartment.
All in all, I love the suspension modification I’ve done to the car. I consider it “done” for the time being. The only things I will be adding soon are the Whiteline endlinks as stated above, and a Whiteline anti-lift kit. I will probably add some Cusco Zero-2R coilovers in a year or two.
Last edited by SilverSurfer; 09-28-05 at 05:40 PM.
This is a great way to go if you are looking for a lot of easy to find engine performance boost while spending a reasonable amount of money. The fit and finish of the exhaust was excellent. Welds were great and the overall design is very good imho. Only thing I would change is the 2.5 inch “neck down” from the standard 3 inch diameter of the pipe at the donut flange after the downpipe. If it was three inches the entire length of the exhaust it would be less restrictive, but I don’t think the neck down will affect power if you aren’t making over 400 – 425 hp at the crank. Above that, and you might be sacrificing a little power, but probably not much unless you are making some really serious power (talking above 450whp here…). All in all, I really like Cobb’s TBE. Sound is excellent. It is very quiet until you are really on the throttle. Even then, it isn’t a high pitched exhaust. It gets louder, but in a deep, rumbling way – which I consider good.
The Accessport was a very handy tool. First of all, you can clear a CEL. This is a nice feature to have. Since I was running a cat with my setup, I didn’t experience a CEL, but it is a nice feature to have available just in case. Besides the CEL feature, it is just so easy to use. I think the AP is a really good bang for the buck modification. When you look at the performance boost for the price – maybe $1400 - $1800 depending on what TBE you purchase (50 hp and 85 ft/lb added at the crank for the stage II) I think it is a super upgrade. The car just had gobs of new found torque down low. Still fell off a little above 6K, but was just a complete monster down low. Around town driving fun factor increases tenfold which is a good thing for me since my STi is a daily driven car…
Last edited by SilverSurfer; 09-28-05 at 05:37 PM.
Standard SBR-GT12 turbo
Perrin FMIC
Perrin turbo inlet hose
Perrin Big MAF intake
Perrin modified injectors
Walbro 255 lph fuel pump
TurboXS RFL BOV
GT Spec II header & uppipe – thermotec heat wrapped & sprayed
Cobb TBE w/high flow cat – top of DP thermotec heat wrapped & sprayed
Hydra EMS
I must say, I was not happy with this setup. I think I sorta set myself up for failure from the beginning though. Instead of taking things slowly and trying to add one upgrade at a time so I could assess whether I did or did not like that particular upgrade, I went all out and added everything above all at once except the TBE and header which were already on the car.
The biggest thing I didn’t like about this combination of modifications was the turbo. The turbo was much too laggy/unresponsive for my taste. I think this turbo would make a decent drag strip turbo, but I hated driving the car around town with this thing. Gears 1 & 2 just sucked. The car was so unresponsive in these gears (b/c the turbo couldn’t build boost quick enough in these gears) that I really disliked driving the car. To be fair, I hadn’t really set up the turbo for optimal responsiveness by adding a FMIC and a header with a very large diameter uppipe. That aside, I knew after about a month that I was going to need a significant change with this setup.
The second problem with this setup was the Hydra EMS. Now, I’m sure there are people out there that love this EMS and I’m not here to bad mouth it. Good for you if it’s working for ya. Personally, it was a very, very bad experience for me in several ways. I’m not going to go into it, I’ll just say I’ve since moved on to another EMS solution....
Due to these issues, I decided to go a different direction with the car.
Last edited by SilverSurfer; 09-28-05 at 05:36 PM.
TopSpeed ECU reflash
Deadbolt TD06H-20G (Zilla)
Thermotec Heat Blanket on turbine exhaust housing
Cobb catless TBE – downpipe thermotec heat wrapped & sprayed
GTSpec II header/uppipe – thermotec heat wrapped & sprayed
Perrin FMIC – Thermotec wrapped & sprayed IC piping, ceramic coated underneath wrap
Perrin Big MAF intake
Perrin turbo inlet hose
Perrin modified 816cc injectors
Walbro 255 lph fuel pump
Modified stock blow off valve (holds 24+ psi with no problems)
SMC methanol injection kit using VP Racing pure methanol
One step colder spark plugs
Cusco turbo heat shield
Cusco oil catch can
Koyo radiator
Crucial Racing coolsafe thermostat (coolsafe = 160 degree vs stock = 172 degree)
Crucial Racing high pressure radiator cap (1.4 bar)
Samco radiator hoses
Redline Water Wetter
I’m very, very satisfied with this setup. The car basically drives like stock, but with a ton more useable power. Gears 1 & 2 are fun again!
You will notice, there is a ton more stuff on the car which is aimed at supporting the higher power levels (better plugs, better cooling system, better heat shielding, etc…). This is an attempt to make the car as reliable as possible with all the modification that has been done with power producing bolt on parts. So far, the car is holding up great. Knock on wood…
I don’t think this setup has quite the top end of the SBR-GT12, but it almost does, and partial throttle response and boost onset is almost immediate. Night and day in comparison. This turbo is a very good match for a daily driven STi as far as bolt on turbos go. I have no experience with the rotated mount setups, but I can say this car is just a freakin torque monter. Lots of power all over the band and in every gear. I’m very happy with this turbo and glad I made the switch.
As far as the EMS goes, I love this “set it & forget it” reflash solution. Like I said earlier, it feels like a stock STi as far as basic driveability. I have the AVCR also so I can turn up boost or down boost as needed. I currently run 23 psi with methanol injection starting at 18psi. The car made 400whp / 410wtq on the TopSpeed Dynojet. As far as dyno numbers go, I don’t even care. The car is just a beast in every gear now and I love driving it every day. Honestly, I’m still amazed how hard this car pulls in 4th and 5th gears. It’s pretty deadly even from a roll. I can’t say enough about TopSpeed. They worked me into their schedule the day after I was supposed to be tuned b/c I was late (due to a Hydra problem) for my appt. On top of that, Doug did a fabulous job on my car. I was expecting good results and the tuning met and exceeded my expectations.
Only thing I would change - I believe my torque comes on later than a car with a TMIC and stock exhaust manifold. It still spools hella fast, I just know it could be better b/c I've seen dyno charts of cars on the TopSpeed dyno with stock exhaust manifold and a TMIC. They made peak torque 500 RPM sooner than my car. This is just me being picky, the car is still awesome imho, I'm just trying to be honest and objective. I have a ported and polished stock manifold, I'm going to get it coated and add it to the equation at some point - just not in a super big hurry to do it since I'm so satisified with the car as is.
Last edited by SilverSurfer; 09-30-05 at 02:47 AM.
sounds like a sweet setup, I hope to go a similar route with the 20G. now let's see some pics!
Yeah, I definitely need some pics. It's a PITA though b/c I don't have a digital camera. I will work on this though. We will probably have at least one more local cruise before it really gets cold here. Will ask one of the other car junkies I know to bring their digital camera so I can get some good shots....
One question what or how did you modify on the stock BOV?
I would like to keep this as I plan on upgrading myself. I've also been tuned by Doug, gotta love it!!!
are you thinking about getting a tmic? which one would you go with?
thanks
david
David,
Actually, I'm not going to get a TMIC. With the bigger turbo, I have seen many dyno charts from TopSpeed and you get alot more out of the turbo with a FMIC. No heat soak occurs in the FMIC like it would with the TMIC. That was a huge factor in performance this summer. We had a record number of days with 90+ degree heat. I think the car performed much better in that type of weather than it would have with a TMIC. Especially b/c my drive to and from work consists of in town, stop and go traffic - the type of driving where heat soak occurs the most.
Honestly, I think the ported and polished / swain coated stock exhaust manifold + uppipe will make a very noticeable difference on spool up compared to my GT Spec II header and uppipe at the cost of a little top end power. I'll probably post results when I do get around to doing that swap and retune.
My STi Review... 
ITERATION #4 - Engine 
