Exedy clutch, Jun Flywheel and STi 12kg Centre Diff
 

As many of you would have known (heard me bitch enough :sad2: ) that my clutch has been a little ordinary for a long time. I finally got around to getting a new clutch and at the same time decided to try out a lightened flywheel. After a lot of research, I decided on a Excedy "Sports Tuff" full face organic kit (new pressure plate, clutch disk and thrust bearing). It seemed the most appropriate for my modest level of power and not too harsh on the gearbox. I also decided on a Jun light-weight chromemoly flywheel (5.4kgs versus about 10-12kgs standard). Jun wasn't the cheapest around but if you get to see one of these, you appreciate the quality. In the midst of all this, I also worked out that my centre diff was destroyed due to a mistake in rear diff ratio (long story but suretrac rear diff and lack of forethought on my part caused the problem), making my car the only front wheel drive WRX in perth when below about 3500rpm. Luckily sourced myself a STi 12kg centre diff (thanks again Stacey) and also the 1:1 drop gears from an STi box to reactify the ratio issues. I've attached a few pics below:

[IMG]http://technik.west-lan.net/Clutch%20pics/OLD%20CLUTCH%20PLATE%20.jpg[/IMG]
As you can see, the old clutch plate only contacted the flywheel with the inner 1/3 of the surface, causing the lack of grip from day 1. I was told that this was due to poor installation :mad:

[img]http://technik.west-lan.net/Clutch%20pics/JUN%20FW%20IN%20CAR%20.jpg[/img]
Jun Flywheel installed

looking the goods darren :)

once she's bedded in, give it a few launches and see what difference that flywheel really makes :icon_thum

[img]http://technik.west-lan.net/Clutch%20pics/EXEDY%20CLUTCH%202%20.jpg[/img]
Excedy Clutch plate installed

[img]http://technik.west-lan.net/Clutch%20pics/CLUTCH%20INSTALLED%20.jpg[/img]
Excedy Pressure plate installed

I've done about 200kms now with the new setup and it is still making me smile everytime. I haven't beaten up on the clutch yet (until it beds in a little) but in gear it feels strong and smooth. The shudder is gone and the clutch pedal still remains extremely light.

As for the flywheel, I'm really impressed with how easy it is to operate. I was concerned that it would be more difficult to get off the line and stop start traffic etc but it's been an absolute joy. Revs pick up so much quicker now it's amazing, in turn helping with turbo spool. Also it seems eaiser to engage the gears when going up, because the revs drop faster and allow the syncros to work more efficently. I recommend this mod to everyone!

As for the centre diff, it has transformed the way my car handles. Drive is proportioned between front and rear equally now and has reduced understeer significantly!! I can't give a quantitive report on the mod though because of the centre diff failure before this diff went in. Guess I'll really know it's worth at the next MC's.

Sorry for the long post but I hope this helps with anyone wanting to venture down this road.

I really want to thank Stacey (for his time, efforts and generosity), Abdus (for the use of the workshop and his time) and especially Jim from Bluestar Mechanicals for his time. You guys are legends and it's my shout next time I see ya!! :)

Darren

looks bling o_0

does the lightened flywheel make enough of a difference to warrant a re-tune ?

[QUOTE=tuna]looking the goods darren :)

once she's bedded in, give it a few launches and see what difference that flywheel really makes :icon_thum[/QUOTE]

Yeah, it's killing me to be this gentle between gears and at starts at the moment. There's so little inertia in the flywheel now and the car feels like it just wants to go at any slight throttle openings. I'm sure it'll help down the quarter mile ;)

[QUOTE=jEstEr?]looks bling o_0

does the lightened flywheel make enough of a difference to warrant a re-tune ?[/QUOTE]

I wouldn't think it needed a re-tune. Engine efficency, boost, timing etc hasn't been altered, it just revs faster!! I'm getting a fine tune next week anyway so I'll have to see.

Darren

nice one darren, I have a JUN flywheel sitting under my bed...

few more good launches and my current clutch will be totalled... so just in time for whoop-ass to start and we will see how long the box holds up for.. :)

[QUOTE=atz 242]nice one darren, I have a JUN flywheel sitting under my bed...

few more good launches and my current clutch will be totalled... so just in time for whoop-ass to start and we will see how long the box holds up for.. :)[/QUOTE]

Mate, remove it from under your bed and fit it!! Honestly, you'll be wondering why you waited!

Darren

now thats the enthusiasim i like to see :)
darrens now a certified mod-addict

if you dont mind, how much $$ for the parts minus labour ? im so want the flywheel

[QUOTE=aDe]if you dont mind, how much $$ for the parts minus labour ? im so want the flywheel[/QUOTE]

Hey mate,

the flywheel retails for $650 but bare in mind, that price is for a GC8, I'm not sure if there are differences in that and your model.

My clutch retails for $750 for the complete kit- new pressure plate, clutch plate and thrust bearing.

Darren