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Attessa Question

Artwear

By Artwear,
in Four Door Family & Wagoneers

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Artwear Contributor

Artwear

Posted
Posted

Is there a link to a detailed thread on the attessa system in the nm35s?

My thinking was its pretty much rwd untill the system senses traction being lost and activates the fwd.

After reading about the rpm diffrence between the break sensor mod while on the stop and go pedals, i wanted to check. Sure enough sat on about 2500rpm as suggested.

Though i did notice small tyre witness marks on the driveway, so tried again the next day with the "Sync" switched on and held it a little longer to be sure, again twin marks.

I would have though the attessa would have not allowed that to happen? Also, i have taken off quckly on loose gravel had had the back spin and step out slightly.

So any more info on the attessa side of things (other then wikkipedia) would be greatly appreciated.

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KiwiRS4T Grand Master

KiwiRS4T

Posted
Posted

Is there a link to a detailed thread on the attessa system in the nm35s?

My thinking was its pretty much rwd untill the system senses traction being lost and activates the fwd.

After reading about the rpm diffrence between the break sensor mod while on the stop and go pedals, i wanted to check. Sure enough sat on about 2500rpm as suggested.

Though i did notice small tyre witness marks on the driveway, so tried again the next day with the "Sync" switched on and held it a little longer to be sure, again twin marks.

I would have though the attessa would have not allowed that to happen? Also, i have taken off quckly on loose gravel had had the back spin and step out slightly.

So any more info on the attessa side of things (other then wikkipedia) would be greatly appreciated.

If you saw two black lines that would be different. Atessa reaction is not immediate. In fact R32 was quite slow. R33 (and Stagea) is quicker and R34 GTR is quicker still. The answer is in your second sentence - attessa senses traction being lost - it can't somehow anticipate it.

MrStabby Grand Master

MrStabby

Posted
Posted

If you saw two black lines that would be different. Atessa reaction is not immediate. In fact R32 was quite slow. R33 (and Stagea) is quicker and R34 GTR is quicker still. The answer is in your second sentence - attessa senses traction being lost - it can't somehow anticipate it.

It does sort of anticipate it, by pushing some drive to the front wheels under hard acceleration, even if there is no slip. The biggest problem with the R32 setup is that its biased much too heavily to the rear. I have a cheapo ebay attessa tweaker in the GTR and it transforms the car. Also R32s also have no preload - ie no drive at all to the front under normal conditions. The R33 and later all send a little drive to the front all the time, which improves response, and is why you need to remove the front driveshaft if you're using a 2WD dyno. In an R32 you can just pull a fuse to use a 2WD dyno.

While we're talking attessa, do NM35s still require flatbed for towing like early attessas?

MrStabby Grand Master

MrStabby

Posted
Posted

If you saw two black lines that would be different. Atessa reaction is not immediate. In fact R32 was quite slow. R33 (and Stagea) is quicker and R34 GTR is quicker still. The answer is in your second sentence - attessa senses traction being lost - it can't somehow anticipate it.

It does sort of anticipate it, by pushing some drive to the front wheels under hard acceleration, even if there is no slip. The biggest problem with the R32 setup is that its biased much too heavily to the rear. I have a cheapo ebay attessa tweaker in the GTR and it transforms the car. Also R32s also have no preload - ie no drive at all to the front under normal conditions. The R33 and later all send a little drive to the front all the time, which improves response, and is why you need to remove the front driveshaft if you're using a 2WD dyno. In an R32 you can just pull a fuse to use a 2WD dyno.

While we're talking attessa, do NM35s still require flatbed for towing like early attessas?

scotty nm35 Grand Master

scotty nm35

Posted
Posted

I have only ever flatbed towed the car. I wouldn't want to try due to the preload on the transfer case clutch though

I have a feeling the M35 electronic G sensor and Attessa computer is much quicker to respond than the earlier units.

Artwear Contributor

Artwear

Posted
  • Author
Posted

So its more of a case of pecentage of power Vs breaking effect?

If theres a constant percentage of drive being sent to the front and you stand on the break and accelerator, is it just the fact that theres less power and larger breaks up front that allow the rears to turn?

M35woah Rising Star

M35woah

Posted
Posted

My car breaks traction when my tyres are really cold or when the steep driveway is really wet or the combination and I cannot get up my driveway as the rear wheel is still spinning and I slide back down. This is at a low speed lets say 5km/h? Even with snow mode activated it struggles going up my driveway.

I can launch my car from 3500 or 2500? pissing down rain with the road flooding and not break traction.

My car also leaves chirp like marks when leaving my garage.

But, if going up a steep hill while raining and I floor it, I can feel the rear slip then the car straightens up then I know that attessa has corrected the slip.

  • 2 months later...
Duncan Grand Master

Duncan

Posted
Posted

FWIW, as well as difference in front vs rear wheel speed from the ABS sensors, and longitudinal G force, they also have a TPS input.

so yep, it's pretty damn good at guessing when you might loose traction.

bloody amazing system for something designed on this

Classic-Games-The-Age-of-DOS-IBM-PC.jpg

Daleo Grand Master

Daleo

Posted
Posted

FWIW, as well as difference in front vs rear wheel speed from the ABS sensors, and longitudinal G force, they also have a TPS input.

so yep, it's pretty damn good at guessing when you might loose traction.

bloody amazing system for something designed on this

Classic-Games-The-Age-of-DOS-IBM-PC.jpg

Yeah, I've watched my torque split gauge throw drive to the front whilst cornering, and encountering a dip; no loss of traction felt, but it is impressive in it's pre-emptive nature.

A wet road would likely have seen a loss of traction in that combination of conditions.

DMM Apprentice

DMM

Posted
Posted

I have not ran part numbers on the nm35 systems, but from the looks of it they run an r34 pump and clutch packs. The only way to confirm would be to look at the g sensor.

If it is R34 data and programming it takes TPS, G sensor, wheel speed and the map sensor. Calculates over a matrix and runs variable prime pressures.

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