iNfEk

iTrader: (33)

Ok so far things haven't been going the way I planned it (then again things usually end up being that way )

well on my on going quest to build my car and accomplish things that people wouldn't normally try ( ) I stumbled upon somethings that may be useful to AUTO owners if you plan on doing this or something similar.

What I am trying to do is converter my US 02 WRX 4EAT to JDM 6spd w STI drivetrain.

1. Interior cabin wireharness IS COMPLETELY DIFFERENT and will not just PnP like the manual cars.

2. Unlike Nissans (done a couple conversions from AUTO to manual) are speed sensors on the AUTO and manual are COMPLETELY DIFFERENT. on the AUTO we have 3 speed sensors on the transmission. NONE of which plugs into the Vehicle Speed Sensor on a Manual transmission.

I purchased MY03 JDM STI driveline from Fine Line Imports with the Brembo brakes including wheel hubs.

3. On the AUTO WRX rear axles splines will not fit properly into the STI rear hubs. there is about 1/4" play in the splines. If you try to just lock down the Axle Nut you will completely destroy the splines.

4. MY03 JDM STI rear axles will NOT fit into AUTO differential. The splines are TO BIG.

I have had several people that have SUPPOSITLY dones this conversion and they stated that the AUTO WRX drive shaft should and WILL fit with my JDM 6spd with R180 rear end.

5. MY02 US WRX Auto driveshaft WILL NOT fit properly with AUTO trans to R180 rear end. The bolts that connect the rear end to the drive shaft doesn't line up.

6. MY03 JDM STI drive shaft (2 piece) WILL fit into AUTO trans and connect nicely with R180 rear end.

Please NOTE: AUTO's have 4.11 in the front and rear differential. R180 has 3.9x. The car will be able to drive with this setup.

The car does feel WAY DIFFERENT though. the rear end actually can come out now

I'll post more when things come available.

started this at 6PM didn't end till 3AM since nothing would fit properly as stated by many people.

Jon

bpang1

iTrader: (25)

Holy crap...my brown friend

You not working today?

luktang

iTrader: (14)

Great info Jon.

iNfEk

iTrader: (33)

yeah I'm working today but I'm heading home now... going to work on the car again. I'll probably have to down the car though

Jon

bpang1

iTrader: (25)

Geez Jon...you're nutz...in a good way.

luktang

iTrader: (14)

Still trying to install the tranny?

iNfEk

iTrader: (33)

yup... don't worry chucky you'll get the trans upgrade soon

iNfEk

iTrader: (33)

oh yeah... after doing all that is stated above I have the EVIL 5MT suspension clunk with my Tein Flex. I didn't have "THE CLUNK" before the upgrade

anyone know how to fix it? I checked the top locking nut and it's tight.

bpang1

iTrader: (25)

Congratulations!

silver satin

iTrader: (7)

Try these Jon

Rear Differential Bushing Kit
The rear differential bushing kit is designed to lock the front of the rear differential support outriggers to where they meet the body. Fitting of the kit will reduce rear-end float, particularly under acceleration, and will help remove the "thump" on hard/quick gear changes.

http://www.subaruwrxparts.com/04sti-suspension.html
Scroll down you'll see them

iNfEk

iTrader: (33)

yeah... I'm already planning to get the group-n bushings later since I don't have money right now

I found the clunk and corrected it

keirnna

iTrader: (8)

Yeah, that is why you have the STi axels. The R180, and R160 pieces are not interchangable. No one has ever said they were, and if they did they are retards.

Same as above. The whole point of the R180 is BIGGER and STRONGER than an R160. To make it stronger you needed bigger splines I guess.

Of course not, it it made to fit the 6 speed to the R180. I told you in PM's the 4EAT and 6MT are not the same lengths.

This will burn out your center diff very quickly. Your wheels are not spinning at the same speed front and rear, and the center diff is taking all of the brunt force of trying to match wrong drive ratios. If that worked without damaging things 5MT guys would be throwing the 4.111 rear diffs on their cars. I know you talked to like 5 mechanics, but other than the subaru mechanic how many of them understand AWD? I am not in any way saying I know more about them, but I know Aaron knows 240's very well, and if have RWD you don't have the same probelms with putting a different geared rear on the car. You very well may destory that 4EAT tranny and make it unsellable. At least before you could have sold it for some cash.

Either way good luck with this Jon. If I wasn't living in an apartment complex where I can't do work on my car I would have already started my swap. I have everything I need now, but I am going to wait until I can get a lightened flywheel and a short shifter.

iNfEk

iTrader: (33)

I do not have a center differential in my auto transmission. it is only in the manual transmission.

if I am going to brake something then I would be breaking something a lot weaker than splines, axles...etc.


in this setup with different gearing (it is not the best choice but a temp solution for my transplant) isn't an ideal situation but the car will drive. of course I won't be driving the **** out of the car but at least the car will drive temp. and still have something to drive if I need to since I have only 1 car.

the reason why you wouldn't do this same thing on a manual transmission is because manual transmissions (or at least ours anyway) have 3.9 gear ratio and the auto trans (rear end) is 4.11. if you were to do the exact same thing on a manual transmission then you would NOT be able to move the car since the other gear ratios besides the rear is a LOWER gear and require more torque to get the car moving. in the case of an auto you can still move the rear 3.9 since there is more torque. of course you will have to start way slower than you would but still I am able to drive my car.

I am repeating this again to you:

the STI drive shaft WILL fit on an AUTO tranny to R180 rear end. The length is the same.

people clearly state that the WRX in general will be able to utilitze the STI rear wheel hubs with no problem. I am just stating for the AUTOMATIC you cannot simply do just that.

the reason for this thread is to give auto owners the heads up on what to expect if they plan on doing anything that I've done and not to just take people that repeat things over and over again from other people seriously!

I just hope that people will be able to use the information that I have provided to learn something since I am personally doing things on my own car and seeing if things fit or not with my own eyes.

I will report more when I finish.

hopefully things will continue very shortly.

Jon

keirnna

iTrader: (8)

I was sure Auto's have a center diff now, I know older legacy's like the 91-94 turbo legacy 4EAT didn't. Why do we put gear oil in for the center diff if we don't have one. There is no way that you'd break an axel or something with stock power, or what you are doing. 600 WHP seems to be were some people have broken one of the rear axels.

iNfEk

iTrader: (33)

service manual doesn't say anything about a "center differential" for automatics.

The center differential is for the manual transmission engines ONLY

Auto's do NOT need to fill for a "Center Differential" we only put for a Front and rear differential and transmission fluid... that's it!

1 fill hole for the transmission fluid (drivers side)
1 fill hole for FRONT DIFFERENTIAL gear oil (passenger side)
1 fill hole for REAR DIFFERENTIAL gear oil

I already posted that I won't break axles. but I will break the weakest link.

Jon