Gtr Awd Torque Split Controllers

[MountainRunner]

This is a break away thread from the World Time Attack Thread, I will put some repeated info at the start so this thread can stand alone.

Background:

This year I had the opportunity to work with Mark Berry and his team on his 2012 World Time Attack campaign. Mark runs two GTR’s at the top level of competition. His R32 GTR which is now famous (being to race at Time Attack in Japan) and his formidable R34 GTR with 530awkw which is a weapon. Those who were at the PM session of the July 19 QR Time Attack track day would have witnessed it put down a 51:46 on the sprint track. You would have also seen the traction problems Mark was having trying to get it to hook up out of corners. This is where I got involved.

Mark had bought my AWD Controller II for his R32 GTR and while he was picking it up we got to discussing the R34 and the problems the car was having. It was clear that I had to build a custom controller for the car (all the Nissan gear was removed, including sensors) and it had to be done before WTAC. The project went extremely well and anyone who was at WTAC at Eastern Creek would have seen the difference. Mark loved the tune ability and after some tweaks the car was pulling over 2G cornering. The AWD Controller II in the R32 GTR also performed, and the result surprised everyone when Mark did a 1:34.66 (that time would have won last year’s open class).

I have a full story of my experience as part of the race team on: www.timeattacktalk.com

I was speaking to Mark today and he said there are no secrets and that I can post up data logging etc from the event. I will put together a write up and get it up on the web.

Refresh From WTAC Thread - Asked about my new 4WD Controller II

The 4WD Controller II is a freshen up of the version I, some of the parts in the version I were no longer available so I did a redesign. The V2 has a better processor and optimised internal algorithms and the output is more accurate. Plus the GPS stuff. Its hard to say if you would notice the difference, it would depend on the rest of the car to some degree and the driver. The V1 controller does a pretty good job, the Version 2 is a refinement.

The Controller in Mark's 34GTR is a whole other story. For that car I had to design the complete ATTESA system from scratch. Mark had removed all the Nissan factory stuff, computers, sensors etc. In that car I have:

1. Front Lateral G

2. Front Longitudinal G

3. Front Gyro Z axis

4. Rear Lateral G

5. Rear Longitudinal G

6. Steering Angle

7. Throttle Position

8. Brake Pedal State

9. Front drive axle speed

10. Rear drive axle speed

The controller then takes all these inputs, does a pile of signal processing and outputs the control signal to the hydraulic system. I also added true linear output control of the valve for smooth operation (not using a simple PWM control signal).

Question: How do the Digital G Boxes Work and Compare that are available

I have had a close look at the digital G boxes on the market (one of the suppliers even sent me some technical info to see if my controller would control their sensor). The marketing is interesting as they are presented to be "faster than the old analog sensors" that are in the factory cars. On closer inspection you will find that they are not actually a true replacement unit as like for like. The digital G boxes are programmed to modify the lateral G sensor as my 4WD Controller does. The difference is that the digital G boxes are fixed to one setting which will be what a particular driver liked on a given day in a particular car at a given race track. My 4WD Controller allows you to tune the unit to the setup of your car and make adjustments on the day. If you have a read of the article I put up on TimeAttackTalk.com I have quotes from Mark Berry on how much he loved being able to tune the unit live.

The digital G boxes are equivalent to one setting on my controller. I'd guess you would get the unit and put it in your car, 'feel a difference' and think it was great but when you went to put down a good lap time end up frustrated that you could not make any adjustments.

Are the digital G sensors "faster" than the factory sensors? I have data logged the factory G sensors and if they are working properly then I don't think there is any issue here. Mark Berry's R32 GTR put down a 1:34.66 at World Time Attack using my 4WD Controller II and the factory G sensor and factory ATTESA. Having said that, if the factory sensor is damaged then replacing it would be a good idea. In Mark's R34 GTR I was testing a new Digital G sensor I am building (it was the front Lateral G and Longitudinal G sensor). The difference is I will make this a true replacement sensor, and my adivce would be to use the 4WD Controller II as the means of adjustment. That way you will have a truely tuneable system.

On a big power, highly modified car such as Mark's R34 GTR, the factory system is well out of its tuneable range. That's why we built a new system from scratch, and as you see from the list above, it takes a lot of inputs to properly control the car. But with this level of control we were able to tune the handling in fine detail and ended up with over 2G of lateral load through turn 1.

[Shoota_77]

Any system that can make a 530awkw get more traction must be pretty impressive!

What method of adjustment does your system use? A dial type setup or can you take it to the next level and make them with a digital readout?

Are you planning on selling these as a kit or do they need to be set up on a case by case basis??

Great work anyway.

[Sub Boy32]

Any system that can make a 530awkw get more traction must be pretty impressive!

What method of adjustment does your system use? A dial type setup or can you take it to the next level and make them with a digital readout?

Are you planning on selling these as a kit or do they need to be set up on a case by case basis??

Great work anyway.

Have a look on his website Shoota, It's all digital display/adjustment

http://www.topsecret.net.au/ruzicengineering/ATTESA_Controller_II.html

[Sub Boy32]

Paul,

You talk about the Digital G-Sensors not being any faster, But what about accuracy? Due to the "Weighted Fingers" in the standard Analog G-Sensor being able to wander around with bumps etc, surely the Digital version should give a better signal?

You talk about speed....Can you see any way that the speed can be increased in the factory pump system, I see this as being the biggest limiting factor in the GT-R in track form compared to the Evo....

Also have you given any thought on picking up the signals from the ABS wheel sensors to shift load?

[Pezhead]

Thanks for posting this up. I picked up one of your Ruzic controllers from a forum member here. I haven't found the time to install it but I'm particularly keen to hear your views on the best way to measure and configure it at a track day. I have a QStarz GPS for data logging as I also love understanding the data you get from the track in learning scientifically in addition to "Seat of the pants".

It's great that you're sharing the info with the community. Looking forward to updates.

[bigmikespec]

With regard to the stand alone system that you have used with the R34 GTR... have you not used a PWM output to control the 4WD solenoid?

[MountainRunner]

1. What method of adjustment?

The AWD Controller II has a display and buttons on the front. You can select maps and tuning from there live as you race. It also shows the LatG, LongG, Torque on the display. For full system setup you can also plug in a laptop and setup everything through the laptop interface.

The controller in Mark's R34 GTR was configurable through the laptop interface only. It also performed all the datalogging at WTAC (I got to get that write up done as well so you guys can see some logging from it)

2. Am I planning on selling the setup in the R34 GTR?

I will put it together as a kit, how it will be setup and user configurable etc I am still working out. I will want to be personally involved in the first few cars we do as I want to work with the owners to ensure they get the best setup and I will use those experiences and feedback to develop the setup and tuning methods. I am planning on making a digital controller that plugs in for live tuning for the driver most likely. The experience we had on Mark's car was that I could tune 80% of the system from the initial data logging and then we worked together to fine tune the handling for the WTAC event.

3. Digital G Sensors, Speed?

You are correct, a new digital G sensor is likely to give a better signal. The ones I am using are Automotive chassis rated and are very nice. The difference would be subtle. My main poiint above about the Tuned Digital G sensors was that the reason the effect is so noticeable is because of the tuning of the output and that having a pre configured tune was not ideal as being able to set it up yourself.

I think a lot of the "slowness" in the factory system is in the ATTESA algorithms, thats why 'tuning' the lateral G sensor can make the car respond a lot quicker. Nissan had to make the car work in all situations, whereas we modify it and want it just right for track use. We were pretty aggressive in the setting up of the 4WD Controller II in Mark's R32 GTR but it has a lot of power 480awkw. In my own car I have the system set to a less extreme value. Mark did find once he had it in the ballbark he could make those fine adjustements to setup the handling the way he wanted it.

In the R34 GTR I could make the torque apply and remove as quick as I wanted. This is where we had to do some tuning, as shock loading the front diff and instantly unloading it is not a good idea both for the mechanical longevity of the drivetrain and also for handling. The ramp rates of the torque are some of the parameters we were tuning on the car.

4. ABS Wheel Sensors to Shift Load?

On the R34 GTR we used axle speed sensors as the ABS system along with all the sensors had been removed. Putting hall effect sensors on the bolts of the drive shafts was a pretty easy way to get speed. We also decided that this was a good way to go as we were only interested in the front to back speed differences, not the individual wheels. To make the system easier to install, I may add the circuitry to pickup from the ABS sensors, although most hardcore track cars have the ABS removed.

5. Setting up the Controller for a Track Day?

The best way I have found to setup the controller is to keep in mind "less is more". You want to find the minimum amount of adjustment you can to make the car handle just right. If you slowly increase the tune of the maos you will find the point where small adjustments can be felt in the under/oversteer of the car. This is what you want. Once you have a feel for the amount of adjustment your car requires you can play with the maps and gain to fine tune. On Mark's R32 GTR, we setup two maps and two gain settings. It was like at the Optometrist where they show you two lenses and ask which one is better. Then show you another two. This is exacly what we did using the toggle switch. Mark would try both maps and gains and pick what he liked best, then make adjustments on that.

5. Controlling the 4WD Solenoid?

I did not use a PWM signal to control the solenoid (a PWM signal is a high speed digital pulse of which the mark-space ratio is adjusted to apply power to the connected device. The connected device smooths the signal due to its mechanical inertia. On some motor control systems you can hear the audio tones of the controller as the motor changes speed). Instead I built a linear amplifier and control the solenoid with a true analogue signal. The solenoid smoothly follows that voltage. The response of the analogue output can be instantaneous if I wish, the speed of the signal (or solenoid) is not limited, it is totally controlled by the handling algorithms.

[fatz]

How much to make my gtr whoosh?

[ordinary]

Thanks for sharing!

What about the weekend warriors out there they just want to have a good auto or base map and only make a few asjustments?

I check tyre pressures about twice all day and really don't do much else so I'm concerned this could be a bit heavy for me...

Thoughts?

[bigmikespec]

5. Controlling the 4WD Solenoid?

I did not use a PWM signal to control the solenoid (a PWM signal is a high speed digital pulse of which the mark-space ratio is adjusted to apply power to the connected device. The connected device smooths the signal due to its mechanical inertia. On some motor control systems you can hear the audio tones of the controller as the motor changes speed). Instead I built a linear amplifier and control the solenoid with a true analogue signal. The solenoid smoothly follows that voltage. The response of the analogue output can be instantaneous if I wish, the speed of the signal (or solenoid) is not limited, it is totally controlled by the handling algorithms.

Is the solenoid actually a pressure reducing valve?

[MountainRunner]

Good question ordinary. I'd go for the 4WD Controller II. Don't worry about the GPS and just use the toggle switch to select between maps or even if your not too concerned play with one map until your happy. I can recommend a good starting point and even set the controller up for you when I send it out so all you do is get it wired in (which is not too hard and your performance shop would do it easy).

fatz: PM sent

[CameronBNR32]

I am interested in setting one of these up in my 33, my torque controller died at the last track day.. what would be the cost of one of these?

[giant]

Hi guys the are great controllers

And the new hardcore one is customizable you would only want it for dedicated high horsepower track cars, but really is fantastic for gtr's

[BunsenBurna]

Subscribed to this thread. Would love to know price and other purchasing info.

Edit: can you still easily flick to 2WD mode with this?

[MountainRunner]

The price is $649, you can order off www.ruzicengineering.com website. That includes free delivery.

It doesn't have a 2WD mode switch in it. Its just built for circuit racing setup.

[JimmyRickard]

PM sent Mountainrunner

[MountainRunner]

thanks for pm. question was about replacement g sensor.

I have one built and tested in mark berry 34 GTR but I am having trouble finding factory plugs so it can be a plug in replacement unit.

seems they are Mitsubishi origin but I can't find a supplier

[Sub Boy32]

Hi Paul,

Can you tell me what Mark controls with in the 4x4 controller with the steering wheel paddles?

[MountainRunner]

The steering wheel paddles are not connected to my controller. I'm not sure what he uses them for. I was pretty focused on the AWD system at WTAC. Next time I see him I will find out.

[Shoota_77]

What changes, if any does changing to a mechanical LSD rear end make to your system?

Do the racing guys generally do it?

Thanks.