jogge

hi, yes the wheel rpm in front and rear is always nearly identical.only if you have less grip at one of the wheels it is different. but this usually is corrected by the traction controll. 50:50 is better for race driving, because if you turn in a corner to fast, and the car beginn to slide, it´s easier to get the car in a straight line with more torque at the front wheels. to do a good controlled drift it´s better to have more torque at the rear. but on track drifting is always slower than "normal" cornering. so also 30:70 is a real good choice. what´s better 30:70 or 50:50 depends also on the drivers style to drive and of course on the diff setup of the front and rear axle.

this is the same i think/hope. but until now nobody know´s exact about this...

how do they do that without wearing out their center clutch ? yes for the cossis´also 50:50 is best and fastest on track. a lot of hillclimb and circuit race cossi´s drive that kind of splitting. i also want to do that in the future but now my front diff is the weakest point of the drivetrain.it´s already uprated with qauife case,quaife internals and a steelplate is also fitted to the case to strenghten the case. but it´s still not strong enough. if a want to have the front diff strong enough, i had to build in a 7.5 inch diff with quaife internals. and also i have to change driveshafts for something with prop-bearings.

but what is about to set it permanently to 50:50 ? is it also always sliding then, or is it full pressured on to have full AWD ? the art of construction of the GTR box is nearlly similar to the Cossi 4x4 box. only the cossi-box has a permanent torque split of 33/66 with a visco-couple in it. so i will think about the option to fit a visco-couple to the transfer case of the GTR box which is fix set to 30:70. but this would be only second option. best would be drive it with the active torque split via a electronical controller. next week the man who had studid electronicall pneumatics is back from holiday and i will talk to him what to do. i think best would be to build a controller unit which bases on the wheel speed sensors and g-sensor of the cossi. this should controll a oilpump system in which we will use a gearbox oil pump. this pump is biuld to run continously. and we will also fit a cooler to the system. the only thing is to find a gearbox oil pump which produces enough pressure. but next week i think i can sort that out.

Thx for explaining !!! I will become a more and more clearer picture of the torque splitting system and the gearbox itself ! but do you think it is possible to set the torque splitting fix to 50:50 or 30:70 ? or does i always have to use it in 2WD mode with an controller to do the torque splitting for AWD mode if needed ? how can i identify a R32 or a R33 GTR box ? i mean whats the difference if i look at the boxes ? do i understand right, that it would be best if i order a complete new built up box from PPG, it´s best to order a R32 GTR box. because that means also i will get the "better" torque splitting system !? i want my car always more oversteer, because that suits most my driving style.

it should be also not a big problem to install the wheel speed sensors of the GTR in my car. but i have already wheel speed sensors at all 4 wheels caused by the use of the traction controll. so i think i have to look in the workshop-manuals of a GTR how the sensors work. i mean at which voltage it operate.perhaps it is compatible with my sensors-output. i always wondering again, what kind of special features the GTR has already installed. WOW !!!!

do you think it is possible to set the pressure in the center case manually to a fixed amount of pressure to have always the same torque splitting ? what kind of pressure means what kind of torque splitting ? the Escort Cosworth is fitted also with a G-Sensor and wheelspeed sensors at all four wheels. so i think it should be possibel to get this all in function with the pectel motormanagement. because the ECU is also running Lunchcontroll,Tractioncontroll.....

in my case it´s not a problem of the dog-engagement. all the dogrings and selector forks are always in really good condition.also after 15000km. no problem. but always having problems on the surface of the gears. the guys from quaife calle it "bitings". and this is caused by the long term use of the box. the gears are not built for use for 15000km. it´s only built up for using at trackdays and races. so normally in one saison less than 5000km.

correct...and also the gearbox case has not to take any significant torque.only the gears take it all. in track day and race operation it´s often a problem that the gearbox case become warm. and because of that it loses stability because it´s alloy. so that´s a big problem for all gearboxes but more a problem for helical-gears. caused by the style of construction of the torque handling in the gears and the box itself.

the gtr was homoligatet for group a. perfect !!! it´s the same like with the cossi´s. all the Escort Coworth have installed a lot of real good parts because of the homoligation. the diffs of my car are 3.62 in front and rear. if we change diff ratio, we only change it rear. and the balancing we do in the transfer case at the ratios of the splitting. the system of the Ford MT75 4x4 gearbox is similar to the gtr box. only without the possibility of active torque splitting. and of course not so strong.....

thx for explaining. so it isn´t necessary to use the gtr diffs. because they are NOT active. ok less work for me.......

so now i thought about something depending on the wet cluch system in the case. i understand how it works, because this is pretty simple like every automatic gearbox will work. but for example with the chrysler corvette with automatic gearbox when you are going for quatermile races, you upgrade your wet clutch system, to get all the power through it without breaking. so i think if you want to run the active torque splitting system of an gtr box in a high powered car you also have to upgrade the center clutch !!! because the system is calculated and built for approx 400HP/500NM ?! i think of these numbers, because the V-Spec version of the gtr is around this. but in asia or i guess also in australia the people run much more than 500NM. and they use the cars on track and strip. so how do they do that with the center clutch ?

thx doodoo for all the help. the pics explain much more than the drawing in the manuals. thx. i will look after that special point on weekend, because in the moment i´m full of work..... and for the diffs 4.11 is not so bad. the cossi is in the moment on 3.62. but i will think if i have fitted the gtr box 5th is 0.75 or something. and on the cossibox 5th is 0.82. so i think 4.11 in the diffs will also be perfect for my use. how strong are the diff´s of the skyline ? do i have to use uprated diffs ? what kind of torque controll do the diff´s have ? is it lsd style diff ? the active diff´s of the skyline do work as the system for the center case torque splitting is working ? so it means i have to have also a pump-system on front and rear diff, connected to a controller (attesa?) ?!

it would be perfect to cool the diff´s and the center case. but only do that with thermostat fitted in every system, which allows the oil to warm up quickly. and only if the temp. exceeds 70-80 degress Celius the thermostat open the cooling cycle. so everything would be fine on street and track use. i think the temps. of the oil in the diff´s, gearbox and so on should be between 80-100 degrees celsius. if temps go higer the fluid will become thinner and the system will loose pressure.

the installing of the gearbox is nearly done. sorry but the camera was out of battery at the moment. but i will post pics at the end of the week. but now we thought about to install the front and rear diff from a gtr because it is possible to manage a active torque splitting including the diff´s and gearbox if i install all the sensors and electronic´s from a gtr. this would be fantastic, because it means it will be a complete active torque controlling system for "low" money. the active diffs and controlling what was used in the WRC Escort Cosworth is a really big bag of money to spend to go for it. so i think the choice of the diffs,gearbox and controllers of a gtr would be a good choice for "normal" money. it´s really amazing what kind of potential the technical site of the gtr offers.....