Front/rear torque split

[sy300]

Probably a stupid question, but what is the torque split on a Stagea?

I have held off asking this, looking for it in the forum, but cannot find an answer.

All I found was that the button on the dash, next to the rear window de-mister, changes it to 50-50 (I think). Can anyone put me straight?

[Sydneykid]

The Stagea runs full ATTESSA (like an R33 GTR, but with different calibration), so there is no one torque split, it is infinitely variable from 100% rear drive to 50/50. The ATTESSA controller determines the split based on the inputs, speed, engine rpm, gear, throttle position and most importantly G forces.

It should not be compared to the simplistic 4wd split that we see in front wheel drive supplied 4wd's. Some of which use the ABS sensors to detect wheel slippage, which is far too late in the equation. Plus they can never go more than 50% rear drive, which limits their handling envelope.

[OC]

Sorry guys, still learning about the Stagea. So as with the GTR's, the tourque is rear derive untill there is slip? Can ATTESA controllers be implemented to the Stagea?

OC

[Sydneykid]

Sorry guys, still learning about the Stagea. So as with the GTR's, the tourque is rear derive untill there is slip? Can ATTESA controllers be implemented to the Stagea?

OC

Nope, there is no waiting for slip. When the G forces indicate a portion of front drive would be beneficial, then the ATTESSA supplies it. It is proactive, not reactive. ATTESSA controllers would work on Stageas, calibration may be interesting though.

[OC]

Cool, thanks SK.

[Techo]

do the stageas come with the cool torque split gauge thats in the GTR's

[Sydneykid]

do the stageas come with the cool torque split gauge thats in the GTR's

Mine didn't, I think the 260RS's did though.

PS; my Stagea didn't even have a boost gauge.

[Duncan]

Do you want to try a TSC Sydneykid

[Sydneykid]

Do you want to try a TSC Sydneykid

Talk to you at Oran Park

[sy300]

Thanks for the info. A good clean answer.

Some of the forums I was in with my 300ZX would burn you for asking stuff like that. Some of them had that 'you are too stupid to own a car' vibe.

[StageZilla]

just on the same topic sorry to hijack the thread but i was wondering if sydneykid could tell me abit more about the attessa setup as i got a few q's

1. does the attessa "release" any drive from the rear wheels (like traction control) when engaging the front wheels or does the rear wheels always drive constantly the same???

2. does 4wd engage on take off launches or is it only in 2wd for the intitial take off?

3. so the front wheels engage (i remember u said its proactive not reactive)before it would wheel spin on take off or low speed coming onto boost?

4. if i release the pressure off the transfer case clutches by removing the hydraulic line will that cause any damage to the clutch packs or tranfer case in general or is it only damaging when the line holds the pressure?

5. what percentage of driving in the attessa pump on? or is based on how u drive? and how much u put ya foot down?

6. does the attessa pump have a constant power supply and an ignition supply? because im wondering why my attessa pump is staying on all the time, its as if its only hooked up to the constant power or something, though it only starts running when i start the car. or does it sound like a sensor issue? its coming up code 75 on the attessa ecu but i still aint got any info on what it means :confused:

hopefully u can answer some of them if ya dont mind

cheers mate

Brad

[Sydneykid]

just on the same topic sorry to hijack the thread but i was wondering if sydneykid could tell me abit more about the attessa setup as i got a few q's

1. does the attessa "release" any drive from the rear wheels (like traction control) when engaging the front wheels or does the rear wheels always drive constantly the same???

2. does 4wd engage on take off launches or is it only in 2wd for the intitial take off?  

3. so the front wheels engage (i remember u said its proactive not reactive)before it would wheel spin on take off or low speed coming onto boost?

4. if i release the pressure off the transfer case clutches by removing the hydraulic line will that cause any damage to the clutch packs or tranfer case in general or is it only damaging when the line holds the pressure?

5. what percentage of driving in the attessa pump on? or is based on how u drive? and how much u put ya foot down?

6. does the attessa pump have a constant power supply and an ignition supply? because im wondering why my attessa pump is staying on all the time, its as if its only hooked up to the constant power or something, though it only starts running when i start the car. or does it sound like a sensor issue? its coming up code 75 on the attessa ecu but i still aint got any info on what it means  :confused:  

hopefully u can answer some of them if ya dont mind

cheers mate

Brad

Hi Brad, wow that's a few questions, my suggestions follow;

1. ATTESSA is a torque sharing system, if the engine has say 200 ft lbs of torque output and the ATTESSA says 100% rear drive, then 200 ft lbs goes to the rear. If the ATTESSA says 20/80 then 160 ft lbs goes to the rear and 40 ft lbs goes to the front. Remember Newton's law, energy can neither be gained nor lost.

2. It depends on the G Forces, I guess a slow take off is 100% rear drive and the faster the take off (G Force) then more goes to the front. Though I have never seen it get to 50/50 on take off. The ATTESSA is smart anough (programmed) to know that the weight shift to the rear means it will have more traction there at high G Forces.

3. Yep it doesn't wait for wheelspin, the G Force sensor tells it there is less chassis acceleration than engine (rpm) accelleration and/or speedo accelleration. In a pure drag racing application, with a high power engine, the ATTESSA controller does not have the ideal programming. That's why the drag racing GTRs have manual controllers or add on electronics.

4. Zero hydraulic pressure = no preload on the clutch plates.

5. It is infinitely variable

6. At all times, when the engine is running, our Stagea has hydraulic pressure in the ATTESSA system. That pressure stays for some time after the engine is switched off.

Sorry I can't help you with the error codes.

[PHATR32]

so the stagea attessa computer would be better than the r32 gtr attesa computer?

would it be worth the effort to wire the computer and sensors in a r32 gtr?

steve

[Sydneykid]

so the stagea attessa computer would be better than the r32 gtr attesa computer?

would it be worth the effort to wire the computer and sensors in a r32 gtr?

steve

Hi Steve , I don't believe that you can, the data transfer rates are different as are the sensor voltages.

[StageZilla]

hey sk thanks for the info again

so the attessa pump runs ALL the time that the engine is running?

also how does running different width tyres on the front and rear effect the attessa? like 265's on the rear and say 235s on the front, what what it cause?

cheers

Brad

[ian]

hey sk thanks for the info again

so the attessa pump runs ALL the time that the engine is running?

also how does running different width tyres on the front and rear effect the attessa? like 265's on the rear and say 235s on the front, what what it cause?

cheers

Brad

Different WIDTH tyres implies different CIRCUMFERENCE tyres (though you can play with the profile to get them closer). Thus one revolution of the front wheel will take you a different distance than one revolution of the back wheel.. Unless you car is growing (or shrinking) in length :-) that would imply either wheel slip or that you are driving the front/back wheels at different rates all the time...

Ian

[Sydneykid]

hey sk thanks for the info again

so the attessa pump runs ALL the time that the engine is running?

also how does running different width tyres on the front and rear effect the attessa? like 265's on the rear and say 235s on the front, what what it cause?

cheers

Brad

As Ian posted, width is irrelevant it is circumferance that matters. Otherwise the front wheels will doing different rpm at the same kph than the rear wheels. The ATTESSA clutches will have to slip to accommodate this, that generater unneccessary heat and wear.

[ian]

... and different width tyres DO have different circumferances (as I pointed out..).

[Sydneykid]

... and different width tyres DO have different circumferances (as I pointed out..).

Not all the time, a 215/65/14 is the pretty much the same diameter as a 225/50/16 or a 245/40/17 or a 285/30/18. Noting that the diameter varies as the tyres wear anyway.

[BensDR30]

The ATTESSA pump only runs enough to maintain system pressure. You will hear it run for a few seconds after startup and then every now-n-then when driving.