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They call me Garrett
98 RBP V4 STi Swapped RS
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4,088 Posts
Discussion Starter #2,341
SG9 Forester STi 6 Speed Swap

Whoa, that's a small amount of words to sum up quite a large amount of work. Let's first discuss the WHY before we jump into the HOW.
Why a Forester STi 6 speed? Well.. because of the gearing. The entire reason I put off a 6 speed swap for YEARS was because I LOVED my V4 STi transmission's gearing. I had driven pretty much every 6 speed Subaru had to offer, and I hated how short they were. It felt like I need to shift 12 times just to get out of my driveway. I won't do the gearing comparison here, because we all have access to the trans charts and Excel, but basically the gearing in the FSTi 6 speed was only around 4% shorter in gears than my V4 5 speed. 4% I can deal with. For some context as to other 6 speeds I have driven, the V7 and V8 STi transmissions are somewhere to the tune of like 14% shorter. That's too short.

So that's part of the why.

Why the other parts of the why?

Front LSD, and rear R180 LSD. Bingo bango. I could have spent the same amount of money (alright, let's be honest, a bit less) on an S201 or type RA V Ltd trans of the 5 speed variety to get that front LSD, but that involved waiting for the deal to come up, with the clutch slipping and me racing in (as of writing this down) less than a week, I needed something that was a bit faster. The FSTi 6 speed will do.

Cool. Makes sense. It's the same transmission, but different in all the best ways.

Moving on to the how.

The how portion get's pretty interesting, and I am sitting down drinking a wonderful Final Absolution made by Dragonsmeade while writing this, so I apologize in advance if as you read things makes less and less sense.

I started by trying to get a hold of J-Spec Auto to see what kind of deal they could get me on one of their 6 speed swap packages. They had two Forester STi packages listed on their site, and I had my eyes on a particular one. Unfortunately, it was a holiday weekend so of course no one was around and I just said "screw it, I need it" and bought the one on their website. 3 text/email/phone calls to my bank later, I assured them the $5000 purchase from the internet WASN'T fraud, and I happily awaited my swap package.







When I got everything in, I began to pull it apart and inspect everything.. and the part that really sucked, was that they shipped me something compeltely different than the package they had listed online. Crap. It was still the proper FSTi trans, and R180 rear hubs and differential and all that stuff.. however it was missing a few things from the listing online, had rusted to hell rear hubs, and two of the same side aluminum control arms. I wasn't too upset as I wasn't planning on using most of the stuff anyways, but the rusted R180 hubs themselves prompted a few emails to J-Spec. I had also planned on having proper stuff from the package I had bought online so I could sell it and recoup a lot of the money I didn't want to spend on stuff I didn't really need. I'll get more into the rest of this later.

A week or so later, the new hubs they sent me came in the mail. They were much better.


This allowed me to start to get to work.... except you may be asking yourself... how was I going to use the Brembos with the current wheels I have on the car? If you weren't asking that, then you already know what I was doing.. I was planing on keeping the 4/2 pots. In order to do this, I needed to use the elusive Group N rotors. How do I get my hands on them? Well.. all sources showed an OLD part number. When I contacted Japanparts asking if they could get that part number, the informed me that a new part number was in their system and gave me that number. I looked it up, and it brought me to STis Group N parts list for use of brakes with 15in wheels. Perfect. I ordered a rear set of rotors ($330, ouch) and those came in the same day the new hubs did.



















As you can see in the pictures, they are the same outer diameter as my R160 2 pot rotors, but they use the larger 190mm R180 e brake inner.

Perfect. I put in the rear diff, and using my old tried and true bolts instead of diff studs, and mounted it all up.








I also got in the R180 5x100 hubs. To do this, I reused my current GC ABS sensors. They mounted up the same, however had different connectors inside the car. Not really a big deal, but it was easier to reuse em... plus the importers had cut the sensors... even though they didn't show that they did in my swap package :stafiseiz.



R180 on top, R160 on bottom.







Mounted up the 2 pots and everything bolted up perfectly. The dust shield is a bit larger, but who cares.

Another thing worth mentioning... e brake cables. I can't remember what the rules were, but I was under the assumption that the R180 handbrake cables were only compatible with R180 hubs, so I used them. As it turned out, they were too short and I couldn't attach them to the handbrake inside. I ended up having to swap back in the R160 handbrake cables... which I really think are just GC cables. So, GC requires GC handbrake cables... whodathunk?!

Here's a picture of the couple inches of difference in the cable.





Next up was to front of the car. Pulled the exhaust, pulled the older trans, etc etc.

When I pulled the driveshaft I realized how long it's been since I had touched this drivetrain (I was 19 when I put it in). I forgot that GCs didn't use the spacers like the GDs/SGs did. Unfortunately, even though the pictures the importers had sent me of the swap package included the proper spacers... they were missing, but I didn't think much of it because I figured I could have just used the ones that were on the car... yeah no.




I asked a local buddy (Tsidreams on here) if he had some spare spacers laying around, and luckily enough for me he did!

While everything else was out, I also took the time to check the up pipe to turbo gasket that I thought may have been leaking and replace it. Yeah....







While it was all part, I took the time to put on the flywheel as well as install a brand new OEM clutch disk, pressure plate, and throwout.

With that done, I got to the heavy lifting.

I hate putting 6 speeds into a car from the bottom, with the engine already in, by myself.. but at least this time I had been able to FULLY drain the transmission so I was able to lift it in with dry sketchiness instead of wet sketchiness.







Next up was the new front hubs. I needed to use the ones that came with the swap package because I needed the male style trans end axles, they were already in the hubs, and they used an axle side tone ring, instead of my old Phase 1 style tone ring around the outside.

While it was out, I also switched over dust shields, changed the ABS sensor mounts and plugs to accommodate for the GC chassis, and on one side installed a new ball joint.

Pictures below:












With everything bolted up, I tossed the hubs and axles in. New rotors in the front too, because why not? I had them sitting around and I had warped my other rotors at the race track -_-





Car was all set, just needed to swap out a few more things in the engine bay, and button her all up.




I also folded up my 5 speed boot for the time being to make it at least a little bit presentable.






Next on the list was to replace the clutch master. I had swapped fluid out like a month ago, and it was already pitch black. I could only assume the seals weren't super duper happy, so I picked one up from the dealer.




Unfortunately while I was removing the hardline, I had rounded the nut on it and decided to just order a new one from the dealer for $9. Should also note that I decided to keep using my old clutch slave, and the reason for that is because it didn't have the damn delay valve in it that all newer cars came with. Won't be needing that junk.





Got my sister to help me bleed the clutch, and put did some wiring to mate up the 4 pin connector for the neutral and reverse switches on the trans as opposed to the GC 2 pin connectors. I also pulled out the rear O2 harness extension and routed my wideband harness down the trans side.

It's a bit of a mess with wiring in that area, but at least nothing is going to get melted.


Exhaust and intercooler went on and in the typical Garrett fashion, it was dark, rainy, and half the interior was together... so I went for a drive.

First impressions: I can't tell the difference in gearing between this transmission and my old 5 speed when putzing around, or giving it beans. It REALLY feels like my V4 STi trans with a 6th gear added in. I can't really speak for if the LSDs are working or not, since I wasn't driving like a wildman, but I'll be sure to report back when I can.

Few things: ABS is on.. turns out I forgot to plug the two wheelspeed sensors in the front in, but I was also getting some codes for a rear sensor.. so I'll have to address that when I can. I don't think it's a tone ring tooth mismatch, but rather something dumb and stupid that I have done.


Clutch feels lighter than the 5 speed one, like all 6 speeds do, but it's SUPER fresh feeling and responsive... and seems to want to hold torque which is a great quality for your clutch to have!


I need to go into the ECU cal and put in these transmission gear determination thresholds, as well as tune away any new driveability issues, should they come up. Also during the swap process I found a nut bouncing around right near my knock sensor.. so.. that probably wasn't amazing. I'll report back with tuning related findings later.

Super happy with the work put in on the car though, everything just feels THAT much more crisp.

All the above work took me about 3 weeks, and a lot of that was waiting on parts and being unmotivated after days of work, but all I have left now is general tidying up and bolting back together the center console and what not.

Will report back one I finish up!
 

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Premium Member
98 2.5RS - V2 WRX Swap
Joined
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1,595 Posts
Super good update Garrett! It’s the nuances like the rare rear rotors that most people will never understand or attempt to implement. Great work...that’s a hell of a well put together machine.


Sent from my iPhone using Tapatalk
 

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Registered
'01 BRP GM6
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373 Posts
Super good update Garrett! It’s the nuances like the rare rear rotors that most people will never understand or attempt to implement. Great work...that’s a hell of a well put together machine.


Sent from my iPhone using Tapatalk
+1!!! Good ish, man!!! Im happy your diligence had payed off, and you overcame the obstacles! :banana: :banana: receiving incorrect purchases, or not-as-detailed items from a used vendor is scary, man.. And I'm glad that they worked with you
 

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They call me Garrett
98 RBP V4 STi Swapped RS
Joined
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4,088 Posts
Discussion Starter #2,345
Super good update Garrett! It’s the nuances like the rare rear rotors that most people will never understand or attempt to implement. Great work...that’s a hell of a well put together machine.
It's a RIOT! I like that I've managed to keep falling in love with this car over and over again!

Rear rotors are something I hope I can help others with in the future, the change of part number thing threw me through a huge loop, so I'm sure it's confused others as well.

+1!!! Good ish, man!!! Im happy your diligence had payed off, and you overcame the obstacles! :banana: :banana: receiving incorrect purchases, or not-as-detailed items from a used vendor is scary, man.. And I'm glad that they worked with you
I'm glad they worked with me as well.. still gotta track down some other parts they sent to an old address (after having already sent me parts to this address???:stupid:), but all in all, it worked out.

Excellent!

I’ll buy your rear diff and axles as spares if you can’t sell the whole kit.
You know where to find me!



Small update from this morning: ABS works fine. Typically it helps if you've plugged in the sensors in the first place..:crazy:


Drove the car around town to drop some clusters in the mail, and stop by the dealership to order some small parts. This is SUCH a riot. The trans feels SOOOOO crips and ready to slam gears with.
 

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Registered
99'RS w/EJ205, 16'340i 13'Volt
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966 Posts
omg so jealous. one of these days i will do the six speed swap!

what are your plans with the 4.44 parts?
 

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Premium Member
2001 SRP 2.5RS/RA/SOHC Monster
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2,740 Posts
Good find on the rear rotors! I've been having a hell of a time finding them myself. Should just order a set now.
 

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Impreza Actual
2001 RS-T
Joined
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1,267 Posts
Nice update. Man your car is like the perfect all around setup.

As far as the diffs go, I could barely tell honestly until I was on track but I don't daily my car.
I have the V6 RA Ltd and it is a dream when you power on early when leaving a corner with that front diff. It literally pulls you into a corner too when you accidentally push wide.

I MIGHT have a used set of the same rear rotors that don't fit my car. If so I can send them to you on the house. I got them as part of a rear drum upgrade for my other car and I have no idea what they are. Would be cool..
 

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They call me Garrett
98 RBP V4 STi Swapped RS
Joined
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4,088 Posts
Discussion Starter #2,352
What size are you wheels? I thought rear brembos will fit under 16s. Maybe not all 16s tho.
17x7.5 +48

Rears aren't the issue, the fronts are. Running rear Brembos with front 4 pots fronts is bad news. IIRC the smaller diameter (may be larger, I can't remember) piston of the rear Brembo causes a pretty decent brake balance problem, and I'm not dealing with that.

Nice update. Man your car is like the perfect all around setup.

As far as the diffs go, I could barely tell honestly until I was on track but I don't daily my car.
I have the V6 RA Ltd and it is a dream when you power on early when leaving a corner with that front diff. It literally pulls you into a corner too when you accidentally push wide.

I MIGHT have a used set of the same rear rotors that don't fit my car. If so I can send them to you on the house. I got them as part of a rear drum upgrade for my other car and I have no idea what they are. Would be cool..
Yeah I went for a slight rip around and could feel the fronts not pushing out at hard. Will find out this weekend for SURE.

May take you up on those rear rotors... I'm a bit worried I'm gonna burn through them with pad incompatibilities like I seem to be doing...

Where did you order the turbo gaskets from? I need to get a few sets but i dont feel like getting bent over by IA Performance...
Shop in Boulder, CO I believe. Can't remember the name but if you search the part number on Google they should come up. It's like IP tuning or something like to IA Performance, but it's not them. I've bought all my twinscroll gaskets from them.
 

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Premium Member
96 Impreza Coupe
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1,578 Posts
17x7.5 +48

Rears aren't the issue, the fronts are. Running rear Brembos with front 4 pots fronts is bad news. IIRC the smaller diameter (may be larger, I can't remember) piston of the rear Brembo causes a pretty decent brake balance problem, and I'm not dealing with that.
Yeah you are probably right, the brembo rear rotors are bigger in diameter than the 4 pot fronts. 316mm vs 295mm. I thought the 4pot front rotor was bigger than 295mm. I must have been thinking of the LGT front rotor.
 

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They call me Garrett
98 RBP V4 STi Swapped RS
Joined
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4,088 Posts
Discussion Starter #2,357
GRIDLIFE Round #5 - Gingerman Raceway - October 5-7 2018




Ah yes, it's the event of the year that took my lovely EJ20k from me last time around...

Gingerman in the cold, wet, autumn weather is a completely different feel than what it is during the summer heat. Everything is a bit slower paced, less rushed, and we even were set to race during complete darkness :crazy:.


Let's jump in:

The car was awesome. The new drivetrain gave me SO much more corner speed that I found myself braking too much (more on this in a second), and driving a line that was wrong for the LSD front. I was used to a bit of push out when giving it the beans in the corner, and the LSD just pulled inward when it was given beans.. definitely something I wasn't used to.

The brakes... well.. I'm still having problems. The high heat judder was back in full effect, and I ate through another set of front rotors in the exact same manner I did before. I have it down to a few reasons:



-Trash rotors
-Trash bedding process

-Trash brake control on my end
-Combination of all of the above


I'm poised to believe I suck at braking, as I had a few guys tell me I am hitting them too hard. I also think I'm never bedding these pads in correctly when switching to the race compounds... I'll experiment with this later on another set of $30 rotors before I spend the cash on multi-piece rotors and trash those.

Because of the judder, all I could really do were about 5-6 laps before everything needed to cool down. I tried doing some cooldown laps during the session, but I kept getting my ass rode by cars and throwing out point bys every two seconds.

Between the brakes needing to be minded, a somewhat wet track, and cars all over my butt, I can say I have never felt more distracted on track than I have this weekend, however that's just another part of racing that I need to get used to.



Another note: I am tired of having a HUGE change I feel like I am debugging, or a problem I am chasing away at the track. Takes away from the actual goal of trying to not suck. That's okay.. only experience can make that happen.

All of that aside, let's talk about racing at night...







Racing at night.. seems like an easy concept... but man oh man does the entire game change once the lights go out. We had a few flood lights setup in crucial spots, but the rest of the track was a void and you really had to dig deep into your memory of the track in order to stay focused.

No one was trying to break records, but we were all definitely hauling as best we could. Braking markers whizzed by like strobe lights, cars popped flames out left and right, sparks from splitters and brakes filled the air and everything felt about 50% faster even though it was obviously slower.

The night racing thing was just absolutely insane, in all of the best ways. I'd hang wide into the void and hope I didn't run out of track to prepare myself for a sharp left that I knew was coming, only to turn in hard and be blinded by the flood lights from another corner and I'd have to make quick adjustments to avoid going two off...

I dunno... it was just awesome. I couldn't get over it the entire rest of the night.

I didn't take many pictures of any in car videos, again, I just felt distracted.

It spit rain the entire weekend, but I don't know where else I'd rather spend time.



More pics:





 

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They call me Garrett
98 RBP V4 STi Swapped RS
Joined
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4,088 Posts
Discussion Starter #2,358
Oh hey, forgot to mention:

Before I headed to the track I did a few things: Group N trans mount, 04 STi Neutral Position sensor, and tossed back in the proper OEM diff studs.

-Trans mount, Forester one was allowing for too much wiggle wiggle.
-04 STi Neutral Position Sensor, The FSTi one was the reversed polarity sensor and showed the car in neutral all the time. AVCS and some boost control is disabled in neutral, so I needed that fixed.
-Diff studs, noticed my bolts were a bit loose when I pulled the R160. Won't be having any of that.





 

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Registered
1995 L
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100 Posts
I’m having the same brake issues. And I think it’s partially me.

I really think you are overheating the rotors, and although they are not yet “fading” due to the aggressive, high temp pads and probably still stop pretty well, I think you are starting to glaze the rotors.

The rotors for the factory 4 pots are pretty small. Even with the best pads and fluid you still need to dump the heat out of the rotors which seem to be maxed out after 4 or 5 laps.

My issue is one of self preservation for me and my car. I tend to be alittle more timid and brake aggressively early and hold it longer. Braking longer at like 90% is worse than braking harder for a shorter distance.

I really need to work on braking smoothly yet quickly to full threshold braking and then smoothly releasing. I tend to stomp on them hard, hold at like 90% for a slightly longer time.

Also... rotor cooling. I have added the factory V4 cooling ducts and have not yet tracked the car after that to see if it helps. I really think we need better ducting and rotors that dissipate heat alittle better.
 

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They call me Garrett
98 RBP V4 STi Swapped RS
Joined
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4,088 Posts
Discussion Starter #2,360
I’m having the same brake issues. And I think it’s partially me.

I really think you are overheating the rotors, and although they are not yet “fading” due to the aggressive, high temp pads and probably still stop pretty well, I think you are starting to glaze the rotors.

The rotors for the factory 4 pots are pretty small. Even with the best pads and fluid you still need to dump the heat out of the rotors which seem to be maxed out after 4 or 5 laps.

My issue is one of self preservation for me and my car. I tend to be alittle more timid and brake aggressively early and hold it longer. Braking longer at like 90% is worse than braking harder for a shorter distance.

I really need to work on braking smoothly yet quickly to full threshold braking and then smoothly releasing. I tend to stomp on them hard, hold at like 90% for a slightly longer time.

Also... rotor cooling. I have added the factory V4 cooling ducts and have not yet tracked the car after that to see if it helps. I really think we need better ducting and rotors that dissipate heat alittle better.
Bolded sentence goes so hard for me too... the the point where I need to buy a shittier car to race...

I have the V4 ducts, though I think one fell off :unamused:

My friend has the exact same 4/2 pot setup I do and has DTC-60s for pads. We also use the same rotor and he hasn't seen nearly as many issues as I do with them getting hot and juddering. His car weighs about the same as well, and he does seem to crack rotors nearly every event.. so... yeah.. i dunno.

I think I need to relearn how to drive, bed brakes in properly, and then maybe consider finding a proper higher carbon steel rotor.

I brought my destroyed rotor into work (we make brakes and brake controls) and hoping I can get some professional insight among the bro science.
 
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