Rallyrigget Nissan Sunny GTI-R selges

[funkes]

Originally posted by aWeX

 

Du bør nok få sjekket nesen din :)

Gti-R har såvidt jeg vet 50/50-fordeling

 

Uenig :)

[Awex]

Originally posted by Essex

 

Gti-R har et firehjulstrekkssystem som fordeler kraften ettersom hvor det glipper, så å si 40-60 eller 50-50 blir litt vanskelig ;)

 

men har kjørt GTi-R selv, og rompa kommer litt om du vil....

 

Veldig mange biler har et system som flytter kreftene mellom de forskjellige akslene. Uansett har de en fast driftsfordeling, som da er fordelingen når man kjører rett frem uten noe slipp på hjulene. På Nissan Sunny GTiR er dette 50/50.

 

På min forrige bil, 323 GT-R, var driftsfordelingen 43/57 , selv om det er et system som fordeler kreftene fremover hvis bakhjulene mister for mye av grepet.

 

Jeg skjønner hva du vil frem til, men uansett har Sunny GTiR ved normal kjøring , som oppgitt fra fabrikk, 50/50-fordeling.

[Awex]

Originally posted by funkes

 

Uenig :)

 

Hvis du leser på GTiR owners club sine tech-sider, kan man lese følgende

There is nothing really advanced about this system and most other 4wd vehicles have a very similar system. As for the 50:50 torque split, it is wellknown that this split is best used on gravel or wet roads

[SunnyGTI-R]

Originally posted by aWeX

 

Stemmer nok det. Husker å ha lest det samme selv. Her er hele historien for den som gidder å lese:

 

 

ATTESA - Advanced Total Traction Engineering System for All-terrain

 

Yep, thats what ATTESA stands for and thats what it does, except it is not so advanced. One thing to note about the ATTESA system in the GTi-R is that it is not electronically controlled. The R33 and R34 Nissan Skyline GTR have the Electronically controlled version of this but that system has the actual name of ATTESA-ETS. The R32 and ["luxury"] GTi-R Nissans have a mechanical system based on so called clutches

 

GTi-R Rear Diff and front diff: It may not be called an LSD by most people but in fact it's design and function are very similar. The basic function of the limited slip diff is to distribute power to the wheel with the most traction. The GTi-R ATTESA set up is built to do this. The rear and front diffs have clutches in them (well almost), these look like a CDROM disc with the last 1-2cm of the CDROM bent out on an angle. These clutches work in a surprisingly easy way. When the person driving the car puts the foot to the floor so to speak there are a several events that happen.

 

1, The power to driveshaft increases.

 

2, The spider gears push the side gears away from the diff towards the wheels.

 

3, This increased load(push) causes the clutches to straighten and lock.

 

4, The lock increases the power to that wheel. (remember this happens to both sides of the car).

 

What happens when a wheel loses traction, The clutch on that side of the diff will lose its lock and therefore power will be forced onto the other wheel. simple??

 

The centre diff on the GTi-R:

 

There are 2 type systems used on GTi-Rs, If you own a rally version you should be able to see the centre diff underneath your car. If you own a road version the centre diff is actually incorporated inside the gearbox housing. The reasons for this are obvious as the rally cars may have needed to have the centre diff changed during a rally and the easiest way to do this is to have the centre diff on the outside of the gearbox. These 2 systems function in the exact same way though.

 

I have heard stories about the centre diffs in the GTi-R about whether they are a fluid/gel based unit or just another locking unit with clutches. I don't know which one it is yet but they both do the same thing it will sense (not really, it's mechanical) the loss of traction and distribute power in the other direction.

 

That is as simple as I can make it and about as much as I know at the moment. When I get more information I will pass it on. There is nothing really advanced about this system and most other 4wd vehicles have a very similar system. As for the 50:50 torque split, it well known that this split is best used on gravel or wet roads.

 

Hope this enlightens some and helps others. Any feedback or other ideas about this system will be appreciated. Dean

 

Anthony Dix adds ...

 

The rally cars (Group A/WRC car not the homologation version) have an active centre diff (hydraulic clutch), just like a R32 GT-R. I assume they also had electronic control using g-sensors and wheel speed inputs. ATTESA is totally rear wheel drive until wheel spin is detected, then the centre clutch is engaged to feed torque to the front. ATTESA E-TS is the same but can also electronically control torque split between the rear wheels.

 

Joe Peterson says (and I believe him!) ...

 

The ATTESA 4WD system is not a true all time 4WD. The rear diff has a viscous coupling permitting both wheels to drive under power, if one looses drive it is then transferred to the opposite wheel locking the rear drive shafts as one, the front is a conventional spider gear diff with no viscous coupling inside thus power is lost when one front wheel loses traction, the front viscous coupling sits between the transfer case and drive shaft to the rear diff, which would allow a certain amount of slip to the rear diff. Drive from the gearbox is always available to the rear wheels through the transfer case. If 4WD was to be maintained all the time ie. 4 wheels truly under power you would not suffer from oversteer as GTiR 's do because the car would be pushed and pulled through a corner not just pushed. If you look at the homologated GTiR its a totally different ball game, as it is a true all time 4WD dependant on what diff and transfer case combination you choose. It had additional electronic torque split and controlled slip diff with an automatic rear torque releasing system. In race or rally cars all time 4WD is feasible as with wheel spin or lifting off one or more wheels during hard cornering you dont suffer from diff bind as you would in a road car. Hope this helps without getting to technical, (all this is out of the w/shop manual & the original FIA GTiR Homologation Grp A Forms)

 

Finally (for now) from Anthony Dix ...

 

I have been in contact with Protech Developments in Melbourne re the GTiR 4WD system.

 

The Nissan WRC car based on the GTiR had an active centre diff under computer control. This car is far from the 'Rally' version available to the public. (i.e. your car.)

 

The two versions available to the public (luxury and rally) had the same 4WD system:

 

- viscous limited slip diff at rear

 

- viscous coupling at the centre (passive)

 

- open front diff