Lateral G sensor

[CONRAD]

Hey guys, could someone post a pick of where the Lateral G sensor is in a R32 gtr/gts4..

Wouldn't mind rotating it and seeing if it improves handling as much as people say.

Cheers

[CSV Imports]

Simplest is to rotate the G-sensor module through 90°. The G-sensor is the gold coloured box located under the centre console, in the very middle of the car. Rotate it by 90° and fix it in its new position. Advantages: results in a far higher degree of front wheel drive torque split in cornering conditions; is the easiest of all modifications. Disadvantages: results in some wheelspin in straight-line acceleration at high revs; power understeer can occur; in wet conditions the car is still a little unpredictable. Summary: Gives an easier car to drive but isn't the ultimate mod.

This Mod is inly if your serious

With the G-sensor orientated as factory, disable the output of the lateral (cornering) G-sensor. This G-sensor input actually reduces the front wheel torque split as cornering loads increase. Cutting the wire results in a fault condition and the disabling of the four wheel drive and ABS systems. Instead, 2.5 volts needs to be constantly fed to this ECU input. This can be achieved by using a voltage divider (pot) as shown here. The pot should be carefully adjusted until 2.5 volts output occurs when it is connected up. Advantages: very large amount of front torque split in cornering; simple mod; superb in wet conditions; excellent straight-line traction. Disadvantages: excessive power understeer in dry conditions. Summary: great "wet weather over-ride" if switched in and out appropriately.

[CSV Imports]

Sorry that I dont have any pics, i hope that info was enough to keep you satified

[Duncan]

Both G sensors are inside the centre console just behind the handbrake

*edit* looks like you beat me with a much better answer

[ferni]

Never heard of these mods, interesting

Anyone else tried them? any feedback?

[Scooby]

Guys;

This is exactly the type of path that Julian Edgar took when he did his famous article for Autospeed. I think it's on here somewhere so a search under torque split controller should produce it. Details different approaches, pros and cons of each etc and gives a circuit for the configuration he settled on.

Good luck.

[CSV Imports]

Yes, thats where I got my inspiration from. He has got a custom built torque control system and says its fantastic, as for me, by just rotating the sensor it can give fantastic results. Trully worth it.

[CONRAD]

Cheers Guys,

Yep I've read that article too a while ago, just wondering where the sensor unit was to try it out.. will give it a crack soon, thanks :cooldance

[Craved]

i remember that he removed the g sensor and replaced it with an amplified signal that was adjustable with a controller in the dash so he could adjust the torque split for different conditions.. one click each for dry, wet, really wet etc ... good article would be handy on cars in improved production for more tunability for all conditions...

do you know if this would be allowed in that class Duncan???

[Sydneykid]

i remember that he removed the g sensor and replaced it with an amplified signal that was adjustable with a controller in the dash so he could adjust the torque split for different conditions.. one click each for dry, wet, really wet etc ... good article would be handy on cars in improved production for more tunability for all conditions...

do you know if this would be allowed in that class Duncan???

We have an HKS adjustable torque split controller on our Improved Production GTR, there are no problems with having an external ATTESSA adjuster in the regulations. The Production GTR has adjustable torque split control via the Standard ATTESSA ECU which has modified software, software is free under those regulations.

Hope that helps

[Duncan]

interesting, I didn't realise you could get at the atessa software...got any more info?

[Craved]

SK ... have you found it making a noticeable difference at that level of tuning?

[Guest mark32]

If anyone is interested i have made up a few torque split controllers using a pic chip with an inbuilt anologue to digital converter for the input side and using pulse width modulation on the output, basically what it does is look at the input voltage and puts out a modified output voltage depending on what setting it is in. it works the same in principle as julian edgars one but is in a fairly small package 40mm * 70mm * 25mm. It has 12 different modes, mode 1 is 1:1 outputing what it sees on the input from g sensor no change from standard setting voltage swing, mode 2 is 10% degradation of the voltage swing upto mode 9 which is a 80% degradation of voltage swing, mode 10 feeds a constant 2.5 volts into the attesa taking away the influence of the lateral g sensor altogether, the other 2 modes are for two wheel drive. the first one feeds a voltage of around 3.5 volts into the attessa which tricks it into beleiving it is going around a sharp corner so biases the drive to the rears, in my gtr i have done a rear wheel spin in a straight line in this mode for about 30 metres before the fronts kicked in so it makes the car very taily, the final mode is just the same as pulling out the 4wd fuse, it is then just constant two wheel drive but also knocks out the abs (same as pulling the fuse) and the car must be switched off and then back on to get it back to 4 wheel drive mode. In my car (r32 gtr) i use the radio control buttons on the left hand side of the dash (am/fm & tuning) to switch up or down the modes and a 5mm led which flashes out which mode it is in. I have had it in my car and a friends gtr for around a month now and it is performing very well to date. I will be fitting one to a r33 gt-r next week, though i dont expect the difference to be as much as the with the r32 gtr but it will be interesting to see how it goes. The box itself is small enough to fit in the console near the g sensors.

[Sydneykid]

interesting, I didn't realise you could get at the atessa software...got any more info?

The ATTESSA ECU came from Mines, it has 4 settings, #1 is rear drive only, #2 is ~20% front drive, #3 is 30% front drive and #4 is ~40% front drive. The G sensors are still there but don't do anything. The car has a Motec ECU with launch control, which switches from #1 (just to get the rear wheels spinning) to #2 then #3 then #4 (if the straight is long enough). Once the gearbox is downchanged, launch control is automatically turned off. This means it stays in #2 or #3 depending on which we choose before the race (ie; it doesn't change). We only use #4 when it is really raining. Note that this GTR has all homologated Group N stuff, ATTESSA clutches, front and rear LSD's etc.

In Production Car Racing we are not allowed to add things like switches or external controllers, so everything is done by software. It doesn't work as well as the switchable HKS controller in the Improved Production GTR, but better than nothing.

Hope that helps:cheers:

[Sydneykid]

SK ... have you found it making a noticeable difference at that level of tuning?

Oh it makes a difference all right, but it also adds another level of complexity. On the Improved Production car we have adjustable stabiliser bars, quad adjustable dampers (high speed & low speed, bump & rebound), adjustable ride height, many sets of springs with different rates, full adjustment in the suspesnion geometry, camber, caster, toe, anti dive and anti squat. By the time you add in adjustable drive, my brain aches trying to tune it.

An example, it has low speed oversteer. Bit more front bar, less rear bar , higher rear roll centre, more neg camber on the front, 1 click on the low speed front damping, 2 clicks on the high speed rear damping and then change the drive 2.5% more to the front. Damn now we have high speed understeer. Around and around we go.................... :headspin:

Too many things to adjust and not enough time, make that NEVER enough time to try them all. :boohoo: