dsycks

iTrader: (10)

See, this is pretty much what I was pondering and what I feel those who have the diff in answered.

It will not help you rotate and if anything makes the car rotate less.

It will however let you put power down faster and harder at apex and later. Turn in to apex however will be slower or at the very least more difficult to do without other attention to details.

theblue

iTrader: (1)

from what I'm reading..

BEFORE the apex it's harder to turn in.
AFTER you've passed the apex it will have a lock that is strong enough to break traction causing oversteer.

this does not sound ideal. At the same time it's always a balancing act with all the parts mentioned. I'm thinking that I want to play with sway bars which are cheaper and more adjustable first, then a diff upgrade if needed. If I didn't already have the medium/high spring rates that I currently have I would try that would be done before sways.

GEARS

iTrader: (5)

Lots of speculation going on here.

First off the clutch plates are not "pre-loaded". They are loose with a decent amount of clearance so that the rear diff is neutral when you are off throttle. This is good because it doesn't effect the turn-in when setting up for a turn nor will it scrub off speed like a 1.5 or 2-way rear diff. You road racer type will know what I'm talking about and will like the operation.

And before you go lighting the witch hunt torches on the forum, yes initially you may notice the clutch plates making some noise while taking tight turns. This is completely normal while they are bedding in. You may speed this process up by doing figure 8's in a parking lot. Also you will hear more noise from the rear diff when you change the sloppy rubber bushings over to solid bushings, if you're going to replace the rear bushing keep in mind that solid metal bushings are going to transmit a lot more noise into the car. I'd option for polyurethane over metal.

As for the concerns about loss of grip, just how does one makes a car exit a turn without having to keep the steering wheel cranked? Get the *** end to slide out a little, helping you complete the turn. This allows you to start straightening the steering wheel sooner which helps with faster exit speeds. I'm not the king of suspension or guru driver but I have to say if you're willing to trade some of the slip angle from the front to the back you'll probably find the EVO faster around the track and a hellz of a lot more fun to drive and being much more forgiving to abrupt input from the driver.

Try it you'll like it!

Jon@TRE

GEARS

iTrader: (5)

Wrong, the car becomes more willing both before and after the apex.

The rear diff is loose, open, non-limited slip...etc when you're off the throttle. Nothing to change in regards to the suspension because the rear diff is not influencing the car.

Get on the gas and you've got a bunch more lock-up which means reduced spinning of the inside rear tire upon exit and that equates to faster exit speed.

The feedback I have gotten from people is that the car is putting more power to the ground at the both back tires and that they have been able to go back to more conventional suspension set-ups that focus on grip, not just trying to get the car to understeer less upon exit.

Worried about the limited slip causing your EVO to come out of a turn slower? I wouldn't be unless something is wrong with the car&driver.


Jon@TRE

GEARS

iTrader: (5)

Come on guys

Loose diff on decel = easy turn-in.
Pre-loaded diff on decel = hard turn-in.

I'm not pre-loading the clutch plates in the rear diff. I'm just getting them to do their job more effectively when you're on the throttle.

Breaking traction at the rear on an AWD car after the apex = good.

Honestly, how many people wished that an EVO would let the *** drift a little more when you got your boot on the throttle versus plowing wide with understeer, leaving the inside open for a Suby to get a bite in on your sandwich...

It's harder to pass a car that blocks the turn because it's sliding sideways.

Jon@TRE

EvoIXMR

iTrader: (66)

Wow, my innocent question has spurned on some serious discussions and brought Mr. Ripple to come answer even. I am honored....

Jon - Can you PM me turnaround time and such? I would like this done in the near future before March?

I will be dropping the whole rear down as I am doing the AMS moustache eliminator brace and all the bushings in the back end and coilovers/rear bar as well....So, I am guessing I will have more noise in the car. Heck, its gutted and has no sound deadening/seats/panels etc - so, a little more noise, I'll live iwth it...LOL

Thanks, Jon!

dsycks

iTrader: (10)

No witch hunt here Jon and you are right that there is a lot of speculation... this happens with any newer modification or item when there is limited information or real world testing and experience to answer myriad questions.

Some of the conclusions drawn were based on very experienced drivers who have used your product in dynamic situations so I don't think that it was rash to conclude that trade offs are involved with this modification but I am very very happy to see you here to add your feedback as it adds a great deal of real information without the need for speculation. My simplified comments were meant to reflect the action of a tight clutch pack on a car from turn in to apex. If you are able however to account for this, I am all ears.

As for adjustments to the clutch pack, do you offer fine tuning to users based on their needs or driving style? Are their any plans to try and do some before and after testing with times and driver impressions? Please don't take this as me being a *****, I only ask as I am very interested in making my car as responsive and predictable as possible and I have a great deal of respect for folks who test their products and let the results dictate the direction of their development.

I still like the idea of a helical rear but a perfectly adjusted clutch pack would be cheaper and arguably just as effective. I would welcome your thoughts on this issue as well as other thoughts on drivetrain development for all sorts of motorsport and daily driving but if you care to focus on open track that would not suck!

dsycks

iTrader: (10)

I agree to a degree. But how much is too much? I will admit that most of the rotation I get in mid turn right now is driver induced and secondary to me feeling my way to the apex and then tightening a little to try to get the car to kick a bit prior to getting on the juice. This is not so bad but your right in that if I get on the power too hard the car will simply bite and push. No argument there at all.

With that said I don't want to end up looking at cars coming at me as I exit turns either. I guess I find it hard to believe that your modification would do that as the front wheels are always pulling and the center diff will also help keep stupid driver tricks from sending me a$$ first off the black stuff and into the green stuff.

Call me over cautious I guess. I will say that the price point of this modification is highly attractive as the possible benefits are very tempting.

theblue

iTrader: (1)

So you're not just welding the rear diff Jon? j/k.

this does sound like a great modification overall and I'm sure they good review will pour in once some more cars have them.

any chance of an exchange program where we return a good core for credit?

GEARS

iTrader: (5)

Good questions will do that.

Turn around time for this is about 2 days IF FEDEX does their part of the deal without any hitches.

Yep, those bushings will transmit some noise but real race cars make noise so you're fine

GEARS

iTrader: (5)

Guys, I'm happy to answer your questions. Most of the time I try to stay working on stuff and not lurking the forums, so please send me a PM and I'll give a reply back ASAP.

I've made some changes and have it dialed in pretty well and the people running the modified rear diff have given it two thumbs up but I can do more custom work for those with special requests. There are some limitations to what I can stuff into the factory housing but for racing I'm sure that most of you will have plenty of lock-up from the rear differential work that I'm offering.

Jon@TRE
www.teamrip.com

GEARS

iTrader: (5)

I do like the novelty of an exchange program and I now offering it.

Jon@TRE

theblue

iTrader: (1)

^^^
nice... I'm back down to having only one car so the cost to me goes way up if I can't do this in a day.

GEARS

iTrader: (5)

Dsycks,

Your concerns are valid and shared by others but we found that any of the Duke of Hazard antics could be tuned out of the car pretty easily without having to throw away your current suspension.

One of our beta testers has an EVO that's pretty fast. When he first installed the rear diff the car was oversteering like a maniac upon exit because he had all the usual stuff done to that car in an attempt to get the EVO to turn; lot of spring, big sway bar, no toe and a lot of air in the tires. After he soften the car up and put some camber in the back the EVO was very stable and still there was more adjustment that could be made to keep the a$$ planted.

We did another beta tester's EVO but this time with more lock-up and he experienced the same thing but was also able to tune the suspension around it. The driver said that the car would turn in as usual, maybe a little less oversteer (because of the extra negative camber) and when he would get heavy on the throttle the car would kick out just a pinch, cleaning the rear tires then hunker down and go where he pointed the steering wheel. Very controllable... and cheap

I don't think that it'll ever be something that'll win you a Tokyo drift trophy but it'll go a long way getting the EVO to rotate.

Jon

ustcc evo

TRE is doing exactly the right thing with the rear diff. We've been doing it in the Evo race car for over two years now, and it works perfectly. The reason it works is because you apply torque to the outside rear wheel which promotes oversteer and better turning.

Most guys resort to taking all the camber out of the rear tires, jacking up the rear ride height, or using way too stiff rear springs to attempt to get Evos to rotate properly, but these are all band aids that don't truly solve the problem.

Some people claim they fix the center diff to solve this problem, but that still doesn't get the torque to the outside rear wheel. Even with a modified center diff, you still need a tightened rear diff to get good balance. Balance past the apex is not a problem with front to rear torque split, as many think. It is a problem of inside to outside rear torque split as even in stock form there is plenty of torque going to the rear tires.

Keeping the stock 1.5 way diff open with on proload under deceleration preseves good turn in, while coming off the the turn you want as much lock as possible in the rear diff.