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Stew's 98RS

129741 Views 674 Replies 80 Participants Last post by  Combat Chuck
The time has finally come for me to organize a members journal! Ive been a member here since I purchased my 98 2.5RS in late December of 2005. My car, not unlike myself, has been through a lot since then and made many changes. And now, upon organizing parts and information for my swap, I though I should get the cars history laid out so I can properly journal its future :D

Current Photos:

Current Mod List 3/13/2023

Engine / Exhaust / Fuel System

Version 9 EJ207
Injector Dynamics 1050X Injectors
IAG Competition series oil pan / baffle / pickup
IAG polyurethane engine mounts
KSTech DBW throttle adapter
2007 2.5i DBW Throttle Body
Roger Clark Motorsports Downpipe
Roger Clark Motorsports Group N turbo-inlet
Roger Clark Motorsports Alloy Cam Gears (Exhaust Side)
IAG V3 competition AOS
HKS Kevlar timing belt
Roger Clark Motorsports timing belt guide
PTP Turbo Blanket
Grimmspeed Turbo Heat Shield
ETS Top Mount Intercooler
Samco intercooler elbow
Tial Q BOV w/Torque Solutions Adapter
Forge BOV
Aluminati Expansion Tank
CSF Oil Cooler (#8119)
RCM Black Series Oil Sandwich Plate
CSF Aluminum Radiator
Spal 12" fan
Samco radiator hoses
iWire radiator shroud
Cobb overflow bottle w/iWire bracket
K&N Filter w/ 3" Vibrant velocity stack & custom inlet adapter
Radium Surge Tank w/Walbro 255
Radium In-line fuel filter
Continental Flex Fuel Sensor

Kotouc (KAPS) R4 Sequential Transmission (P2 ratios 3.33 / 2.38 / 1.80 / 1.37 / 1.06 / 0.84 )
Version 9 Sti 6MT transmission TY856WB8KA
Version 9 R180 rear diff
ACT StreetLite flywheel
Exedy Stage 1 Organic HD Clutch
OEM Exedy Clutch
Goodrich Stainless Braided Clutch Line
Torque solutions transmissions mount (poly)
Torque solutions solid carrier bearing bushings (Aluminum)
Kartboy transmission crossmember bushings
Whiteline front and rear shifter bushings
Torque solutions solid shifter u-joint
Whiteline rear diff bushings (rear crossmember)
Whiteline T-frame bushings
IAG Competition pitch stop

Suspension / Steering
V9 STI 5x114 hubs
V9 STi subframes (front/rear)
V9 STi sway bars (front / rear)
Feal 441+ Coilovers w/Swift springs (10k/8k) (9k/8k)
Swift Helper Springs
Professional Awesome 777 Bumpstops
JDM GC8 STi Aluminum control arms
Whiteline ALK
Whiteline roll center kit
Whiteline control arm bushings
Whiteline lateral link bushings
Whiteline trailing arm bushings
Whiteline rear endlinks
Whitleine rear sway-bar mounts
Whiteline 22mm adjustable rear sway bar
Whiteline 22mm adjustable front sway bar
SwayAway front endlinks (for 2015 STi)
2015 STi Steering Rack
L&E Rack steering shaft adapter
Whiteline steering rack bushings
Chasebays power steering reservoir
Mooresport power steering pump adapter
IAG -6an PS high pressure line, custom -6an return line, custom -8an suction line

C6 Z06 Corvette 6 piston front calipers w/12.8" STI Rotors
STi Brembo rear calipers
Stoptech Stainless Braided Brake Lines
G-LOC R12 / R10 Brake pads
Centric blank front rotors
Brembo blank rear rotors
CompBrake brake servo
Nameless performance 18" Hydro Handbrake

Enkei PF05 17x8.5 +48
WedsSport TC105X 17x8.5 +43
Falken Azenis RT660 235/40/17
ARP Extended wheel studs

Interior / Safety
Sparco Sprint seat on custom fabricated mounts
Sparco steering wheel
Snap-off R1000 quick release
Custom roll cage built to SCCA GCR specs (1.5"x0.120" DOM)
Schroth Profi 3x2 FIA Harnesses
Renscott Harness Collars
6OC lightweight door panels
181stleader Carbon fuel tank access covers
Custom central switch panel
6OC Drivers floor plate
iWire DBW pedal adaptor
Flocked Dash
Rennline/Rennscot fire extinguisher mount w/Maxout 2.5lb extinguisher

Aerosim Research carbon fiber race roof
V6 / RS front bumper w/Fog light covers
JDM Smooth rear bumper
JDM Lightweight bumper beams
JDM Rear spats
JDM Taillights
JDM Clear Corner Lights
Clear side markers
L'aunsport S5 WRC style Rear wing
Bakemono 22B Hood Vents
Bakemono Carbon S201 Mirrors
Shaved side moldings
Shaved trunk
Custom Pearl Blue paint
30% Ceramic window tint
RPG Carbon WRC Mirrors
RPG Carbon Exhaust Shroud
V5/6 Replica front lip

Haltech Nexus R5 VCU
Haltech PD16 Power Distribution Module
Haltech 15 Button CAN Keypad
Haltech 8 Button CAN Keypad
Haltech TCA-8 CAN Thermocouple Module w/Prospeed connector brace
Haltech CAN Hub
Haltech TMS-4
ECU Master Dual H-Bridge module
Plex SDM700 Digital Dash Logger
Custom motorsport wire harness
MAPDCCD Center Diff controller
MSEL Solid state battery isolator
Odyssey PC680 Battery
2006+ WRX DBW Pedal / Throttle Body
KA NTC2 Fast motorsports IAT sensor (Intake Manifold)
RIFE IAT charge cooler temp sensor (Intercooler)
Lowdoller Motorsports oil pressure sensor
Lowdoller Motorsport oil temp sensor
Delphi Flex Fuel Sensor w/Raceart Mount
MAC 3port EBCS w/Raceart Mount
AIM Sport 2k PSI brake pressure sensors
Hella Sharptones Horn

My name is Steven and this is my long-standing journal documenting the path of my 1998 2.5RS from purchase, daily driving, to now many years later restoration and transition into a dedicated track car. The most recent phase of this project has taken me roughly 6 years. 5 years, but I'm getting close to having a complete car, with the goal for a running driving car later this summer (2021). I'm at the point now where the car is so nearly road-worthy. I'm making a big push, and the goal now is to have it track ready by July 2022. I've now been using and enjoying the car from the summer of 2022. A project like this is never "complete" but its in some version of done. I'll continue to update this as it continues to evolve.

Original Intro from 2005
Heres my Introduction and story for how I got my car:
My name is Steven Stewart and I'm from lower West Michigan. When I was a freshman in college I was in the market for a new car after crashing my first car, a 95 Nissan Altima, into a telephone pole in the snow. Im not exactly sure what sparked my interest in Subarus but It was pretty quickly that I decided I wanted an impreza.

I browsed Ebay, autotrader, craigs list, news papers and such for a couple weeks looking for a new car. One session on ebay, I clicked on a link for this wrecked blue 98 coupe but just glanced at it and moved on. Later, I returned to that link and realized it was about 40min from my house! So the next day I went and looked at it, drove it around the parking lot (it was salvaged title, thats all I could do :( ) and immediately fell in love. They wanted $5500 for it off the lot and that was way too much so I decided to bid on it on Ebay. I Lost the auction to a sniper and it went for $3600 :( I was pretty sad I didnt get it. Anyways, two days later i found it listed again on Ebay! I called them right away, offered $3600 cash and picked it up the next day!

12-21-2005 Purchase!
Heres two pictures the dealer used on the ebay auction

And here she is at the body shop I worked at the day I brought it home

After this, I began the process of rebuilding my new purchase.


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I like it. The lip adds the needed depth to make the side profile look even.
Couple of things....

I aligned the car the other day. I was able to get the rear to my goal of -2.5 degrees of camber. Previously this was maxed out at -1.5. The front, I could still only get -2.5 degrees which is confusing because thats as much as I had last year when I set it. I further modified the front camber plates which should have added more but...maybe just not enough. In any case, This is a good start.

Also, I painted the replica lip. Really happy with how this came out.

Finally, I made a new intake setup. My goal was to reduce intake temps by getting outside of the engine bay. Ultimately I settled on going through the chassis in front of the passenger fender / tub. This puts the filter in front of the passenger front tire. I will build a shield to protect the filter from tire spray, and also I'll be using a dry pre-filter thing that wicks water away.

An initial drive seems to indicate this works - on a warm day I would easily see IAT's exceeding 50-60C especially when sitting in traffic. With around 25C ambient temps, I didn't see IAT's exceed ~45C. I don't have good back to back data but This does seems lower than it would normally get. In any case, it's better than bein in the engine bay.

Overall really happy with where the car is at the moment. AND I've got some more exciting stuff coming this week...Hopefully...

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So damn clean! good idea with the intake routing.

are you referencing the IAT at the filter or right before the intake mani?
So damn clean! good idea with the intake routing.

are you referencing the IAT at the filter or right before the intake mani?
I'm referring to the temperature in the intake manifold. I measure the intake air in two spots - one location is in the intercooler before the throttle and the other is in the intake manifold plenum (stock location on some JDM long runner manifolds). There's usually about a 10°C offset between those two, with the intake manifold always being a little hotter.
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That's a significant drop! Did you consider phenolic spacers to get temps down a bit more?
Looks spectacular! I've been wanting to get a front lip and rear spats for some time now.
That's a significant drop! Did you consider phenolic spacers to get temps down a bit more?
I haven't considered it. I'd be worried about hood clearance with my BOV. I might be over-thinking it, but It was already pretty tight.

Looks spectacular! I've been wanting to get a front lip and rear spats for some time now.
Thankssss...Definitely would recommend this particular lip for the money.

And since I'm here...a small update: Added some gold foil tape to the new intake tube...

And a little teaser of something going in this weekend....:devilish:
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And a little teaser of something going in this weekend....:devilish:

jealousy intensifies
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Man that's looking great! I've wanted to make the STi sequential for so long. I bet its going to be a blast.

Is that just a samco upper radiator hose? I put my extra Koyorad radiator in my GC and I'm having a heck of a time finding a good solution to keep the upper hose off the bolt for the power steering pump. That hose looks like it has ample space.
Man that's looking great! I've wanted to make the STi sequential for so long. I bet its going to be a blast.

Is that just a samco upper radiator hose? I put my extra Koyorad radiator in my GC and I'm having a heck of a time finding a good solution to keep the upper hose off the bolt for the power steering pump. That hose looks like it has ample space.
It is a Samco hose. It's trimmed a lot on the radiator side. Like probably 1-2" in order to make it not interfere.
Glad that rep worked out for you. Looks fantastic!
Alright, A moment I've been waiting for...For many years for this to even become a possibility and then for many weeks for it to be delivered after purchasing. About 10 weeks ago I ordered a Kotouc R4 sequential kit through Rallispec in New Jersey. Originally, I went with the Kotouc over an X-shift because their R4 kits are identical and the X-shift was on an 8 week lead time where the Kotouc quoted 2 weeks. "quoted" ...... 8+ weeks later Rallispec received the parts and about a week later it was in my possession.

So here it is, a Kotouc Subaru R4 Plus sequential with their P2 ratios, assembled into an 08+ 6mt case. Being 08+ meant I lost the vehicle speed sensor in the transmission, but this is not an issue for me since I have both wheel speed sensors and GPS speed.

Unfortunately, this is much later than I had hoped to be doing this. I've got literally one week before my first event of the year, and here I am making a major change to the car. But, so it goes. Off I went - My buddy trailered the car to his shop where we had a lift to use.

It wasn't long before we had the old box out and the new one ready to go in. Before though, we installed a new Exedy stage 1 HD clutch. Not really required for this, but a "while I'm in there" type of thing.

The shift lever took some fiddling to get the linkage correct. This involved cutting and tapping the linkage they had provided. In the end though, we got it fit up, did the break-in process and I was off for a test drive.

The thing is so much fun. I wired up the gear position sensor and the shift lever sensor however I still have a lot of calibration work to do to get the gear cut right for clutchless shifts. That will take a little time, and maybe this weekend will be a bit of a shake down. But, overall....I couldn't be happier with where this car is. It's everything I ever wanted for it, and I'm so proud of what I've built.

So, next week: Gridlife Midwest Rev-up. I'll have an update after that!
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I wish I could like this twice 🤣
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Letsss fuckinnn goooooo!

See you soon, doood!
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That's awesome progress! I hope it performs exactly as it should on track!
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Thanks Dudes!

I've spend a lot of time this week already calibrating the flat-shift cut for clutchless upshifts. It's definitely a tricky function to get right. I've gotten shifts down to around 60-70 miliseconds at higher engine speeds and full load. I'm still working to reduce the shift effort, and make sure things feel smooth and are safe for the gearbox itself. I'll share some data soon-ish.
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Well, first Gridlife event is in the books. Midwest Rev-up is kind of a warm-up for the big event in two weeks, and I definitely was going into this treating it like a shakedown for all of the changes I made to the car in the offseason. I was hoping to see some big improvement to my personal best time at Gingerman however that didn't happen. Really no major issues with the car, however some perplexing stuff.

First, I've had a couple lambda sensors go bad in the car already since last year. So, recently when my lambda sensor started flaking out, I though nothing of it and ordered another Bosch LSU 4.9 sensor. We installed it at the track on Friday night and I didn't test it until Saturday morning. Strangely enough, the sensor is still flaking out. The Haltech is reporting an error for the signal value but no circuit codes. For this weekend, I turned off the closed loop control above 4000 RPM and added a little fuel to the base map in the higher load regions just to be safe. The car ran fine this way, but I don't like not having this working, so I'm going to dig into it more.

Secondly - Flat-shifting with the new gearbox. I don't have a good frame of reference for what's good or bad feeling of a sequential flat shift. Like, I calibrated the function enough that it works. I yank the lever back with my foot to the floor and the car changes gear. However, It still requires a good forceful rip on the lever. Also there are still times when it feels jerky and sometimes when it feels smoother. I made some changes over the course of the weekend but I'm not really sure if I'm going in the right direction or not. Also, there were some occasions of miss-shifts and a couple of nasty sounding downshifts into 3rd. Hoping I didn't do any damage and it's just driver error.

Finally - The car just lacked pace. That, or more likely, the driver lacked pace. It could be because this was my first event of the season and I'm a bit rusty, but I was hoping to set a new personal best time this weekend given all the updates to the car. However, I never set a sub 1:40 lap all weekend (I had gone into it shooting for a 1:38.X). On my last lap of the last session, I was on a predicted 1:38.8-ish lap but I overshot the final turn and took the car through a sand trap. Thankfully I didn't do any damage to the car, but man was I bummed out I didn't put the lap in. There's a few things on my mind as well - I had the camber in the rear of the car come out of adjustment at the struts. So I need to do something about that so I'm positive it's not shifting. Secondly, I think I can and should get the car even lower. That, and I need to go through all of the data I collected and see if I can learn anything more about what direction to take the car.

But! Despite some trouble here and there, it was still an excellent weekend. All things considered, the car ran pretty well. I had a great time hanging out with a lot of good people and my two good friends to towed the car for me and helped work on the car all weekend. The car got a lot of positive feedback - people love the thing and it feels amazing every time someone compliments it. I even got pulled aside for some photos for one of the Gridlife photographers. Also, the car looks rad with stickers on it. Officially a racing car now.

So, some work to do over the next two weeks. But overall pretty happy. The car is still a blast to drive, and ripping on the sequential is good fun.

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Also, got some photos from a friend this morning...!

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Annnnd one more. I'm in love with this thing.

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Are the rear lowers on your feal coilovers slotted? I've been dealing with a similar issue of camber slipping at the knuckle on my Cygnus/Fortune auto coilovers. I prototyped a couple of washers that would lock the lower in place by filling the slotted hole. One version centers the bolt in the lower the other give you the option to run max negative or positive camber at the lower. You might look into something like that. Here's a picture of the prototypes. I'm still trying to get a few sets machined for testing.

Silver Automotive tire Grey Wood Font
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