cusco center diff?

[kicavoky]

ok I've read all the threads on here concerning center differentials, but where can I get a cusco center diff thats 65/35 for my 1g

 

[wortdog]

Most places list it as being for the EVO3, if that helps.

Here's one place that has it:
http://www.napsusa.com/cgi-bin/napsusa/510-020-A.html

 

[kicavoky]

thanks, that place is way expensive.... Do I have to buy a center LSD and a front LSD in order for the center one to work?

 

[wortdog]

No, you do not need a front LSD, but it would show even more improvement in grip coming out of corners.

I believe Fedja (MrAWD on here) has one in his autocross car and can probably give you a better place to buy it from/more information than I can.

 

[cait sith]

http://www.rxecret7.com/culstageceev.html

Best price you're gonna get it for.

Fedja doesn't have it, ACM (charles) does.

 

[kicavoky]

ya I found that site, thanks though. As for the guy who has it, what do you think about it?

 

[jtmcinder]

No, you do not need a front LSD, but it would show even more improvement in grip coming out of corners.

Yes, but there would be a cost of a front LSD entering corners.

- Jtoby

 

[cait sith]

Yes, but there would be a cost of a front LSD entering corners.

- Jtoby

That's why you get a one way LSD. No lockup on braking and full lockup on acceleration. Although, that's just THEORY talking. We'll see experience next year.

 

[jtmcinder]

If Kaaz makes a one-way for our front, then, yes, that takes care of the corner-entry problems I alluded to. But I don't know of they do and, even if they do, a Kaaz is not as good a front for corner exit as a Quaife.

As we say in the AWD world: there's no such thing as a free launch.

- Jtoby

 

[cait sith]

If Kaaz makes a one-way for our front, then, yes, that takes care of the corner-entry problems I alluded to. But I don't know of they do and, even if they do, a Kaaz is not as good a front for corner exit as a Quaife.

As we say in the AWD world: there's no such thing as a free launch.

- Jtoby

Cusco makes a 1 way front LSD for early EVOs/DSMs that they reccomend to go along with the 35/65 diff.

They actually reccomend having both front and rear LSD's with the 35/65 due to the whole fact that the torque split is lock.

I'll be trying a Cusco front/center KAAZ 1.5 (Maybe Cusco) once the funds pour in. It's just a matter of the whole spending approximately 3 grand at once.

 

[kicavoky]

too bad our cars come stock with vc's so aftermarket front and rear lsd's arent neccesary (this concept has been approached numerous times in other threads)

 

[cait sith]

too bad our cars come stock with vc's so aftermarket front and rear lsd's arent neccesary (this concept has been approached numerous times in other threads)

Notice how I said RECCOMEND. But hey, if you want to have a piece of crap open front diff, a weak sauce gob of goo VLSD or even better an open diff rear end, be my guest.

 

[wortdog]

The stock center viscous coupling is not adequate for autocrossing a car with more than stock power. There is a very noticeable delay before it begins locking, which leads to smoking the inside tire on corner exits, despite being AWD. The lockup can be abrupt, which changes the cornerning attitude of the car. The same problem can occur with the Cusco diff, as it uses the stock coupling. The Cusco takes a bit more power to do so than the stock diff.

I apologize for confusing who had the diff.

 

[jtmcinder]

too bad our cars come stock with vc's so aftermarket front and rear lsd's arent neccesary (this concept has been approached numerous times in other threads)

What the heck are you saying?

- Jtoby

 

[jtmcinder]

Cusco makes a 1 way front LSD for early EVOs/DSMs ...

That's cool, but -- in theory -- I'd still avoid modified clutchpacks in the front of a car that needs to turn tightly.

- Jtoby

 

[MrAWD]

The stock center viscous coupling is not adequate for autocrossing a car with more than stock power. There is a very noticeable delay before it begins locking, which leads to smoking the inside tire on corner exits, despite being AWD.

I wonder how you came to all of these conclusions. For the first part, I raced my car with all stock diffs in SM with power above 350 HP and never had any problems with center diff (or the front one as well).

As of the second part, you are very wrong there!! Center diff has nothing to do with the inside rear spinning. That is the job of your rear diff. With better rear diff, you would not have smoking of the inside rear. As a mater of fact it is actually great that stock center diff is capable of overdriving the rear wheels the way it does, which at the end just make the car looser and you can end up with better times at the end.

The last thing is about smoking your inside rear tire at the corner exit phase, which makes even less sense. I bet that you have to do several mistakes in your driving in order to make your inside rear to smoke that bad at the exit of the corner. All of this is of course under the assumption that you have at least correctly working rear diff (stock or not).


Fedja

 

[wortdog]

I wonder how you came to all of these conclusions. For the first part, I raced my car with all stock diffs in SM with power above 350 HP and never had any problems with center diff (or the front one as well).

As of the second part, you are very wrong there!! Center diff has nothing to do with the inside rear spinning. That is the job of your rear diff. With better rear diff, you would not have smoking of the inside rear. As a mater of fact it is actually great that stock center diff is capable of overdriving the rear wheels the way it does, which at the end just make the car looser and you can end up with better times at the end.

The last thing is about smoking your inside rear tire at the corner exit phase, which makes even less sense. I bet that you have to do several mistakes in your driving in order to make your inside rear to smoke that bad at the exit of the corner. All of this is of course under the assumption that you have at least correctly working rear diff (stock or not).


Fedja

I never said rear tire, my 1G hazes the inside front tire coming out of tight corners. If the center coupling locked or even nearly locked, the front tire wouldn't spin, even with an open differential.

Plus, I was on all-seasons and stock springs/shocks, which amplifies the problem.

Edit: I agree with you that spinning the inside rear on a DSM would be challenging.

 

[MrAWD]

I never said rear tire, my 1G hazes the inside front tire coming out of tight corners. If the center coupling locked or even nearly locked, the front tire wouldn't spin, even with an open differential.

Sorry my bad there seeing it as an inside rear! But, what I wrote still applies between the center diff and the side of the car that is spinning. That is the job of the diff that is on that side of the car, so in your case your front diff. If you would have a better diff in there (only Quaife comes to mind here), then that spinning would be better controlled. And the point being that center diff has nothing to do there and it shouldn't be used for something that is not supposed to do! It should only control how much it should be sent to the front and how much to the rear. That is it! Two other diffs should control things between the left and the right side!

Edit: I agree with you that spinning the inside rear on a DSM would be challenging.

Actually, few years back I had an excessive spinning of my inside rear at the Pro Solo finale (I think that was my last year in ESP before I moved to SM) but only on one side of the car! Since I try to drive with the throttle through the whole corner, at the entrance phase, car would slow down with acceleration until the wheel would be back on the ground. And that was happening only on one side of the car.

That problem was fixed on following Monday before the Solo2 runs with adjustable end link on my front sway bar. Since there was a preload on the bar, one side was doing great while the other stayd up in the air. Evening out of the preload fixed the problem.


Fedja

 

[wortdog]

Sorry my bad there seeing it as an inside rear! But, what I wrote still applies between the center diff and the side of the car that is spinning. That is the job of the diff that is on that side of the car, so in your case your front diff. If you would have a better diff in there (only Quaife comes to mind here), then that spinning would be better controlled. And the point being that center diff has nothing to do there!!

Ahh, but if one of the front tires is spinning, then the casing of the front differential will be spinning at that higher speed than the rest of the wheels, which will show as a front/rear speed differential to the center diff. If the center diff locks quickly, the front diff will slow to the speed of the rear diff, which keeps the front inside tire from spinning.

Actually, few years back I had an excessive spinning of my inside rear at the Pro Solo finale (I think that was my last year in ESP before I moved to SM) but only on one side of the car! Since I try to drive with the throttle through the whole corner, at the entrance phase, car would slow down with acceleration until the wheel would be back on the ground. And that was happening only on one side of the car.

That problem was fixed on following Monday before the Solo2 runs with adjustable end link on my front sway bar. Since there was a preload on the bar, one side was doing great while the other stayd up in the air. Evening out of the preload fixed the problem.

I remember having to diagnose similar problems when I was on an FSAE team, one of which was a bent front swaybar. I'm suprised there was a preload on a stock style bar, but I suppose the tolerances on stock suspension parts aren't very good.

 

[MrAWD]

Ahh, but if one of the front tires is spinning, then the casing of the front differential will be spinning at that higher speed than the rest of the wheels, which will show as a front/rear speed differential to the center diff. If the center diff locks quickly, the front diff will slow to the speed of the rear diff, which keeps the front inside tire from spinning.

Yes, you are right about this, but (isn’t there always a “but” you are still trying to fix one problem by fixing something else. Usually that has a price to pay and in this case you would have your car tighter than you would like it to be (except if you are core drag racer of course).
By fixing the front diff (the side that is actually spinning) and leaving your center the way it is, your car would be much nicer to drive and faster if I can say!! The fact that VC equipped stock center diff has that delay is actually the best feature of that locking mechanism!

The thing that you have excessive front wheel spin, points out to few other things that could be causing this behavior. You could have badly adjusted suspension for first (which you mentioned something about), then you could be overdriving your car and being too aggressive with the right foot! Remember, smoother is always faster!!


Fedja