anybody use a 5mt with 20kg VLSD center?

[sniper1rfa]

Sortof thinking my next purchases will be some differentials. Thinking about the 20kg center and a cusco 1.5way rear, while leaving the front open (since i'm not keen on the ridiculous amount of understeer a FSLD would add, on top of the already stupid center... :eek:).


My concern is that the 20kg may be too much for a DD. I can deal with a little tightness during parking lot maneuvers but don't really want it to be super noticeable on the commute to work.



I'm mostly doing it because i want a rear LSD, and that would seem a little useless without a stronger center as well. I've come to grips with the fact that i suck at tight corners, and would really like to just toss it through, power out, and take the time penalty for a crappy line. :shootsself:

Not to mention i'd like some more AWD action while driving in the snow - one wheel wondering is lame.



Any thoughts? Other suggestions for alternative setups?

[williaty]

You know, I've had this same line of reasoning in my head. Must be a wagon thing.

[sniper1rfa]

Could be...


first i need to get up enough scratch for a new pair of shoes and a belt. :-/

[carl]

Sortof thinking my next purchases will be some differentials. Thinking about the 20kg center and a cusco 1.5way rear, while leaving the front open (since i'm not keen on the ridiculous amount of understeer a FSLD would add, on top of the already stupid center... :eek:).


My concern is that the 20kg may be too much for a DD. I can deal with a little tightness during parking lot maneuvers but don't really want it to be super noticeable on the commute to work.



I'm mostly doing it because i want a rear LSD, and that would seem a little useless without a stronger center as well. I've come to grips with the fact that i suck at tight corners, and would really like to just toss it through, power out, and take the time penalty for a crappy line. :shootsself:

Not to mention i'd like some more AWD action while driving in the snow - one wheel wondering is lame.



Any thoughts? Other suggestions for alternative setups?
shouldn't be a problem ;)

[UP2MTNS]

that's exactly what I have....stock open front diff, 20kg center, stock rear vlsd.

its fun....100% different car w/the center diff...definitely makes it all more 'tight'.


let me put it this way...on a level surface, you can't push the car forward/back. even on a slight downhill, the car won't roll on its own....its weird.

on tight corners/parking, you'll get some rear wheel chirp...and you can't 'coast' into a parking spot, you gotta stay on the gas.

driving on the high way, I can't event tell...but i haven't really been DD'ing this car since I installed it....no idea what it does to mpg's.

I don't know what it would be like if you put a real 1.5 way LSD in the rear with it....but right now, like I mentioned in that other thread, the car acts more like RWD in corners.

I think for DD a 12kg might be a bit more easy and still just as fun.


and I still grapple with why an LSD up front would cause more understeer, wouldn't it grab MORE than an open diff (on corner entrance) and pull the front around? now that the front outside tire that is usually getting no power from the open diff, is now getting driven by the LSD?

[williaty]

and I still grapple with why an LSD up front would cause more understeer, wouldn't it grab MORE than an open diff (on corner entrance) and pull the front around? now that the front outside tire that is usually getting no power from the open diff, is now getting driven by the LSD?
Because that's not really what's happening. With the open diff, both front tires are receiving the same amount of torque but are free to rotate at different speeds, which is good because it's demanded by the fact that they're tracing out different circles. Once you toss a *simple* slip limiting mechanism into the mix, the slip limiter tries to equalize the wheels' speeds. This uses up some of the outside wheel's available grip slowing it down and uses up some of the inside wheel's available grip trying to speed it up. The net effect is that you have less traction available for turning. The stronger the slip limiting mechanism, the sooner this negative effect on turning sets in.

Now, fancy-pants diffs can actually get around this. That's one of the reasons manufacturers are so keen on electronically controlled diffs. You can create a diff that will still allow different wheel speeds (up to a programmed limit) but at the same time can send more torque to the outside wheels, helping the car to claw it's way around the corner.

[sniper1rfa]

that's exactly what I have....stock open front diff, 20kg center, stock rear vlsd.



well, that explains why you were still running around with a busted rear diff. lol.


I find it strange that you can't push the car around or coast nicely - in a straight line your diffs should be doing absolutely nothing.


i'm not interested in sourcing the parts needed for the 12kg unit.



edit: and carl? bite me. :mrgreen:

[UP2MTNS]

nah...didn't have it in then....stock center diff back in March still.


and out of curiosity, other than the diff itself, what other parts do you have to source for the 12kg diff? how's that any different from sourcing a 20kg one?

[sniper1rfa]

different transfer case, you need to get an old school (pre-98?) MT and use the back half of it. Plus, i think the 12kg is harder to find, since it's not for modern transmissions.

[UP2MTNS]

oh, right, this isn't for a wrx....got it.

[sniper1rfa]

12kg unit doesn't work on any USDM WRX either.

[bp_968]

What do the various STI's have in them stock?

[sniper1rfa]

They all have DCCD center (a planetary diff with a magnetic clutch LSD) and helical fronts. '04 had a clutch type rear, the rest have helicals.

[sniper1rfa]

NASIOC is so useless. Posted this over there and basically got "GTFONOOB"

[me_jimmy]

NASIOC is so useless. Posted this over there and basically got "GTFONOOB"

GTFONOOB = huh?http://hem.bredband.net/jimwoo/smilies-filer/freak6.gif

[sniper1rfa]

get the **** out, n00b

[jbrady]

I have an obx front (helilcal), 20kg center, and stock crappy viscous rear in my 02 wrx and the front diff will actually help pull the car throught turns in lose conditions. The center diff helps this also since the stock weak center will redirect the power to the rearend (since it is lighter with less weight) and not let the front get enough power to pull you around the corner. The 20 kg center seems to make the car push on high grip situations the most (Pavement). No real negative side effect for DD other then that which you get used to.

[RA Limited]

i'd like to revive this thread for more input and thoughts:

i'm in the planning stages of a WRX build that will probably take a while, and i have access to cheap parts now... so i am stockpiling stuff.
I could plan for building up a 5spd drivetrain, with front OBX, 20kg center, and some kind of rear clutch type (either R160 GC8 STi unit, cusco, kaaz, whatever).... alltogether, wouldn't this be like half of a 6spd swap?

Would you guys say a built 5spd for ~$2000 is worth it and totally awesome, and that i shouldn't waste the extra 2g's going after a 6spd setup? (i think i know the answer to that) :)

Thanks!

Just a thought.

[williaty]

Wait... R160 clutch type?

Tell me more, tell me more!

[UP2MTNS]

i'd like to revive this thread for more input and thoughts:

i'm in the planning stages of a WRX build that will probably take a while, and i have access to cheap parts now... so i am stockpiling stuff.
I could plan for building up a 5spd drivetrain, with front OBX, 20kg center, and some kind of rear clutch type (either R160 GC8 STi unit, cusco, kaaz, whatever).... alltogether, wouldn't this be like half of a 6spd swap?

Would you guys say a built 5spd for ~$2000 is worth it and totally awesome, and that i shouldn't waste the extra 2g's going after a 6spd setup? (i think i know the answer to that) :)

Thanks!

Just a thought.

for $2K that's a great deal.

and I don't think its 'half' of a 6sp swap, and will cost you a lot more than the extra $2K plus a lot more work. You'll have to replace axles, hubs, etc, etc, etc.....

[snicker]

I have a STi ra Active center diff from a 5 speed jdm tranny. Does anyone know if I can swap it into the jdm Legacy gt tranny I'm using right now? It's a 4.11 pinion tranny and the active ra center diff is from the 4.444 STI RA tranny.

[RA Limited]

Wait... R160 clutch type?

Tell me more, tell me more!


haha.

Well, looking over UpGarage's listings, i have found a few STi 1.5 and 2 ways, i believe they are R160's- i know they did make them, but the descriptions on UG's site are pretty vague and they don't always know for sure themselves..... but long story short, i'm looking at $600 for a front and rear STi clutch type setup if i want it. I think 6spd missions go for under 2g's over here if you look hard (just the mission), and i could get my old 4.44 drivetrain back for cheap if i wanted to. I have a ton of options.

I don't want the 4.44 for my car in the states, because it will be my wife's daily, and we'll be doing lots of 6+ hour drives in it. The car will mostly have simple boltons, some gravel wheels, and hopefully LSD's- nothing too fancy.

also- drivetrain work i am ok with doing myself. I've pulled a ton of missions and clutches and stuff like that, although mostly on nissans. It's just engine and tuning stuff i dont like! :)
BUT- should i pass up a cheap STi RA V6 gearset?

http://www.upgarage.com/upgarage/stock/1/2/0903153002764/153

http://www.upgarage.com/upgarage/stock/1/2/0812146005692/146

http://www.upgarage.com/upgarage/stock/1/2/0903153002757/153

[williaty]

Do you read JDM? Trying to figure out how you find what upgarage.com even is selling.

[RA Limited]

for $2K that's a great deal.

also, just so we are on the same page- i'm saying ~$2k investment to get three LSD's into my drivetrain, but still having stock 02 WRX gears. I mean, i know i won't be drag racing or really even doing much at all on pavement, but i will beat the piss out of it offroad.

[RA Limited]

I use google translate. I order stuff off there often, but it is not a fun process. I pretty much use google translate for 90% of the transaction, up to when they call me to schedule delivery- then it is a horribly akward phone conversation.
Generally, to find what i want, i just search for general things like "GC8 LSD" or "GC8 VF" (for turbos)....

DISCLAIMER: i do not want to run a parts buying/shipping service for anybody- i just lined up some stuff for Burney (he is here too, but too lazy to do this himself) and it was a major PITA. I probably won't even order much for myself anymore.

[RA Limited]

ok, last night i found a 20kg STi center on a site i've never bought from (japanese) and i'm trying to get it. It says it's new/unused, they have it labelled as a STi Center 2-way (looking at it, it's totally the same 20kg i've been looking at/for), and it is Y40,000 ($415ish).
I emailed them last night about it. Hopefully i can pull it off.


So from what i've read, this diff feels and acts somewhat like DCCD in or towards the "lock" position? If that is an accurate description, then i can totally see why it would kick ass for rally use.

[UP2MTNS]

^^ for rally use, yes it kicks ass....if your wife is getting a lot of groceries in it, its a little rough for medium to tight turns on paved surfaces (even with stock F/R diffs). maybe get the 12kg one?


$2K for 3 diffs is still a good deal. my rear carbonetic LSD was $800 even after 'sponsorship' discount. Center diff brand new is also expensive, same with front...although, I've also been told the OBX front LSD is a good, economical choice.

If you can do all that work yourself? score.

It'd be better if you didn't have the '02 'glass' gears, but yeah, if you're not putting down big numbers you should be fine.

[Draco-REX]

a Front LSD can increase grip as well. It's all in how you drive it. After going to a V7 6-speed in my WRX, I now have a front SureTrac LSD. It definitely handles differently. It doesn't tolerate the timid. If you try to finesse the car around corners by getting on and off the throttle, the nose will hunt around. Give it a little more gas, and the nose will push wide as you'd expect. However, if you *commit* to a corner, the LSD will pull you through it.

At the last RallyX (which was the first with the new transmission) I was having a hell of a time getting the nose to go where I wanted it. AT one point, I was so pissed when I went wide, I just said "F- it!" and stood on the throttle. Suddenly the car took off like a shot and it just carved through the corners, going exactly where I wanted. I would definitely recommend a front LSD.

[Draco-REX]

They all have DCCD center (a planetary diff with a magnetic clutch LSD) and helical fronts. '04 had a clutch type rear, the rest have helicals.

USDM STIs, do all have DCCD, with the 05+ getting a Yaw sensor added to it.

From 04-06 they had clutchpack rear LSDs, the 07+ have mechanical.

Earlier JDM 6-speeds had the DCCD as an option. My V7 6-speed has the same viscous 4kg center diff as the stock WRX.

[RA Limited]

^^ for rally use, yes it kicks ass....if you're wife is getting a lot of groceries in it, its a little rough for medium to tight turns on paved surfaces (even with stock F/R diffs). maybe get the 12kg one?


$2K for 3 diffs is still a good deal. my rear carbonetic LSD was $800 even after 'sponsorship' discount. Center diff brand new is also expensive, same with rear...although, I've also been told the OBX front LSD is a good, economical choice.

If you can do all that work yourself? score.

It'd be better if you didn't have the '02 'glass' gears, but yeah, if you're not putting down big numbers you should be fine.

awesome, thanks for the info.

My wife daily drove our old STi RA with DCCD, so she is no stranger to aggressive cars- now my beater drift car 180 she didn't like- but she loves subarus.
I think i will possibly leave the stock center in during the warmer months if we dont like the 20kg for daily, then put the 20kg in for winter stuff for better traction. The center should be pretty easy to swap out.

Draco, you aren't the same Draconis on NASIOC are you? I sold my Ver6 STi RA heads to a Draconis guy IIRC.

[RA Limited]

a Front LSD can increase grip as well. It's all in how you drive it. After going to a V7 6-speed in my WRX, I now have a front SureTrac LSD. It definitely handles differently. It doesn't tolerate the timid. If you try to finesse the car around corners by getting on and off the throttle, the nose will hunt around. Give it a little more gas, and the nose will push wide as you'd expect. However, if you *commit* to a corner, the LSD will pull you through it.

At the last RallyX (which was the first with the new transmission) I was having a hell of a time getting the nose to go where I wanted it. AT one point, I was so pissed when I went wide, I just said "F- it!" and stood on the throttle. Suddenly the car took off like a shot and it just carved through the corners, going exactly where I wanted. I would definitely recommend a front LSD.

what i found with the front suretrack in my old STi RA was it really liked LFB.

[UP2MTNS]

awesome, thanks for the info.

My wife daily drove our old STi RA with DCCD, so she is no stranger to aggressive cars- now my beater drift car 180 she didn't like- but she loves subarus.
I think i will possibly leave the stock center in during the warmer months if we dont like the 20kg for daily, then put the 20kg in for winter stuff for better traction. The center should be pretty easy to swap out.

Draco, you aren't the same Draconis on NASIOC are you? I sold my Ver6 STi RA heads to a Draconis guy IIRC.


not a bad idea (swapping diffs)...the center is actually VERY easy to swap out (relative to anything else in the drivetrain).


off topic....jeebus, my spelling sucks. did I really type "you're wife"? :unamused:

[RA Limited]

Score! i got confirmation from the seller on this 20kg diff. It's mine. $450.
:D

now i'm just waiting on my bank to give me the ~$7k i need for the 02 WRX i'm getting lol.

New garage thread coming soon!

[A1337STI]

Woot!

and BTW changing your Front diff to LSD doesn't = understeer automatically

Helical is a style of cutting the gears you can have a helical open diff, a helical torsen

If your differential is "limited" via Speed and its not a 1.5 way or 1 way THEN you get massive understeer due to the outer tire needing to spin faster then the inner.
so if you have a trick 1.5 plate that is 50% lock under braking, but open under coast you can 'coast' through the corner with out understeer, and on power its 100% lock up
hense the 1.5 way name. so if you try to stay WOT through a corner it will remained locked and likely understeer you, if you lift while you turn get the needed rotation then back to WOT it will work like magic.

a Welded diff always has both sides spinning the same speed, so turning forces one of the tires to slip .

a viscous uses fluids and magic to allow a slight speed difference but locks up under too great of a speed difference (not good for your front axle)

the 05+ sti's have a helical cut Torsen
the 04 has a "sure trac" which is a name brand , i think its a helical cut torque sensing similar to a Torsen but it's not using worm wheels and worm gears : http://www.iwsti.com/forums/drivetrain-components/1420-suretrac-differential-what-does-mean-sti-owners-long.html

it was only used in 04 and switched out in 05, i think the Sure trac is a bit more speed sensitive along with Torque senstive where as the 05 is a traditional torsen that is only torque sensing (like the obx one)

:)

[A1337STI]

at least from what i've read, never driven a 1.5 way or a welded :P

[RA Limited]

i've driven 1, 1.5, 2-way, welded, suretrac, DCCD, viscous... between Nissans, Hondas and Subarus that i've owned or driven at some point.

1.5 is awesome for up front in FF or AWD once you learn how to use it. Suretrac/Helical LSD in the front is useless in comparison (IMHO). 1.5 is good in the back for an aggressive car that you will street drive. 1 way in the back is a waste of time.

[RA Limited]

i got the diff today, it is still in the original packaging. :)

QUESTION-
i have read on a few places that it is intended for non-abs cars only.... is this just a "suggestion" from subaru? Does the ABS not like a crazy center diff?

[T-Heineken]

i got the diff today, it is still in the original packaging. :)

QUESTION-
i have read on a few places that it is intended for non-abs cars only.... is this just a "suggestion" from subaru? Does the ABS not like a crazy center diff?

ahhh come on. Just pull that fuse. I haven't used my ABS in 2+ years...and I am in the snow every other weekend during the winter :)


It's awesome you have the opportunity to grab some good diffs and these prices.

I wish money grew on trees...then we could just buy, try, and figure out what worked best on our cars for the type of driving we do...then we could have a DD car, a winter car, a rally car....and since your in Japan....our baller JDM fly rides yo:
http://www.jagpromotions.com/images/jstyle/bvan2.jpg

[d'cheat]

What is it with JDM and over the top vans!?! A buddy of mine went over there for two years, came back with a bunch of LOL type van conversions.