Dallas J

iTrader: (1)

I need more than just the ACD log in Evoscan, I need it with the data I get from the chassis datalogger. It has plenty of analog inputs for logging too but I need to know what the pressure and pressure change is while also being able to see what the car or I am doing.

Ayoustin

iTrader: (2)

I don't think you understand, he can give you some blanket statement "the diff will lock more or less in X and Y conditions" if that'll make you happy. But the actual work itself he's doing to achieve that, he would be stupid to post about publically.

IMO TRE has become so well regarded for two reasons, Jon pays extreme attention to detail, and he understands how drivetrains and their components behave under different conditions.

The dude runs a VERY small company and he knows his stuff, I think he's being smart. Quite frankly, after spending some time talking to him, it's understandable why he runs his business the way he does. Lots of people contact him asking bull**** questions and waste his time.

I'm not saying Jon is the be all end all and knows everything and that you shouldn't waste your time going to other people. There are plenty of other companies that will take your money.

kyoo

iTrader: (29)

i totally agree with this. i remember talking to him a couple of years back and him discussing how the animosity among some of the trans builders is way overstated. shep has seen some of tre's transmissions and has asked him how he has the time to do everything he does to them.

kikiturbo

aha.. ok...
THere is one possible issue that you might encounter. Logging line pressure, or even just solenoid voltage will give you the acd clutch pack pressure. However, from what I have seen, when we logged all the ACD/AYC ecu data (G sensor inputs, individual wheel speeds, steering angle...), the main deciding input was actually steering wheel angle change rate, or steering input speed... So you might want to log that too with your system if you can.. The ACD system was quite open during steady state cornering but it would go beserk with quick steering input.. ofc, that might be lateral G too..

Dallas J

iTrader: (1)

At least getting pressure logged would be a start but definitely want to add in steering angle. That one I need to wire an arduino and program it to count the OEM steering angle encoder. Should be simple enough, just gotta add it to the list of things to do.

With pressure alone, I can at least correlate any pressure oddities on course to see if its effecting the handling. I need to go back to the OEM tune and basically start from there as Im chasing a high steering angle push in places and corner exit push if throttle is applied to early. So logging pressures I should be able to track that down to too aggressive front diff setting or center diff pressure.

Front diff is the Mfactory 1way clutch restacked to 60% but I may pull it to restack down to 40%.

kaj

iTrader: (60)

I think you misunderstood the second paragraph of my post. I said i don't need to know how he does it, just what he's doing. . So yeah, knowing what he's doing would make me feel better.

I'm not saying there's anything bad about his business or how he does things. He's done work for me and I like him, personally.
I'm saying I personally don't respond to "ask me how" ads. Nor "click here to see why Hollywood fired Roseanne", "progress starting at only....", blah, blah.
You are free to explain why Jon does it, but it won't change my shipping habits.
Also, as someone above mentioned, we're all kinda past the gimmicky stuff at this point. Unless he's trying to attract the kids that are finally able to buy these cars, then I get it.

kyoo

iTrader: (29)

another disappointing day for the osg in autox - haven't gotten wheelspin like this in a long while. this thing is barely a limited slip diff. the cusco is probably the right call here.

i can talk to osg about the setup, but i already know what they will say - the problem is with the car and that i need to keep both wheels planted.

LetsGetThisDone

iTrader: (1)

It's doing 1 tire fire on you?

kyoo

iTrader: (29)

around 10s and 50s, where the engine just kind of revs freely without accelerating - tire in air is spinning. yes, the car is a little out of shape in those spots when I'm trying to get on the gas, but that's autox sometimes.

doesn't happen or at least didn't notice on track.

kyoo

iTrader: (29)

so - some props to OSG who already responded discussing my setup. they said given the tripoding, there are a number of ways they can get the diff to lock up more and/or respond faster - but what i want, i'm not sure.

i.e.: more clutch plates activated - that will decrease some of the wheelspin for sure - is that the solution? OR, do I get faster acting ramp angles (55, up from 38) - will that do the trick? Or both of those things? Or, less negative preload? More regular preload? Faster lock timing? i think the difference between less negative preload & more preload, btw, is that preload is the static preload level, and negative preload will unlock the diff to get it there.

to summarize, my options to choose from (not mutually exclusive):

1. activate more clutches
2. increase ramp angle (38 to 55)
3. less negative preload
4. more preload
5. faster lock timing

I'm leaning towards doing both 1 & 2 - essentially to get it closer to what the cusco did on power, without losing too much of what the osg does off power. what sucks is, i'm really not the most financially well off to spearhead this kind of testing, but i do think if i get it to a place i'm happy with, it will essentially be the "evo-spec" for osg's.

CaptainSquirts

iTrader: (3)

Hmmmm I never experienced my engine just free reving in a corner. We almost have the same setup. I do get a wheel lifted on the inside rear but it is planted by the time I need the power.

Corner like this I get wheel lift and at the turn around, but by the time I'm accelerating, the rear is already planted.

I'm running 24mm whiteline rear sway on the softest setting, but I also have helper springs in the rear with my coilovers. So maybe the helper spring allows the tire to be planted by the time I need it to be. You could always try throwing on stock rear sway bar or try getting some helper springs in the rear. Also noting that the inner bushings on the upper control arm limits droop travel, view pic below. I never measured it after but with that bushing, it wouldn't allow the rear helper springs to fully droop. I did add super pro bushings so Im going to assume it doesn't bind after a certain limit.

Video has been posted before but here is a view of my setup looking at the rear suspension on the course. I didn't have the new bushings installed so Im going to assume I have a little less lift but regardless, still have some in a couple scenario's. But it doesn't bother me where I need the rear wheel down.

kyoo

iTrader: (29)

i never experienced it either... on the cusco. i have experienced it on the oem diff. are you on the osg?

i am discussing with them best options for the diff to lock harder/ more aggressively

CaptainSquirts

iTrader: (3)

In the suspension video I was OEM restacked, I am running TRE Max Lock now.

ronaldo9

iTrader: (2)

I didn't want to start a new thread so bumping this one. Has anyone had experience running a helical differential in the REAR. I saw quaife and mfactory make a helical rear differential and curious how that would make the car handle versus having clutch plates. Also from a maintenance stand point it seems to have benefits there.

kikiturbo

Since the Evo likes to lift inner rear wheel in corners I would guess (never tried evo with helical rear) that that might pose a problem.