Simon a.k.a. 'Si'

"The Ruzic Engineering 4WD Controller certainly made a huge difference to getting the power down. Plant the accelerator and hang on as you do massive AWD power slides. Started off with it set to just a bit above factory torque and found it was still very tail happy, so upped it a fair way and the difference was awesome!"

Michael a.k.a 'Jetman'

"I have had the Ruzic Engineering 4WD Controller and Thermo Controller in my car for some time now and have not been able to fault them. My GT-R is my transport to work, where it sits in the sun all day and also shows up to the occasional Track Day. The Controllers are compact and robust enough to fit anywhere you want them to in the cabin. I have one mounted above the center gauges and the other in the center console. They are easy to read at night when I’m traveling home from work at 02:00 and don't distract you from the road. The testing that I have done has mainly been at Track Days where I started using Map 1 with a zero scale factor. My car would be extremely susceptible to over steer on most corners. Switching then to Map 3 using the toggle switch, with 80 percent scale factor, I would be able to apply acceleration earlier out of the corner and not have any problems with over steer, just a nice 4wd power slide. Glancing quickly mid corner at the torque indicator, I do remember seeing the needle moving up around the 30 to 50 position at times. The indication lines are close together if you know what I mean. Hard to pinpoint accurately the amount of torque to the front wheels. I am waiting for a Data Logger Cable to arrive to plug into my PDA, so I can log everything it is reading.

Now my car set up is not the greatest for any Track at this stage by my standards, it is good on the road, but on a track, (different kettle of fish), so to make my tail happy car very close to neutral, and giving me better control on fast and slow corners, is fantastic.

I know many hours have been spent on this project, probably nearly adding up to two years R & D trying to make a product that is user friendly, extremely accurate, sturdy yet robust with an easy to read large backlit LCD display, and dam well perfect.

This 4WD Controller is fantastic and a blessing for anyone out there that is having problems with over/ under steering on a GT-R, GTS-4 and/ or anyone who just wants to fine tune there ride for road or track."

Peter a.k.a.'Maccattack'

"Some of you may have read about Paul Ruzic building and (now selling) 4WD Controllers for GTR's. I purchased a unit from Paul and was "testing" it in the car on yesterdays Time Attack day at QR. I thought I would provide some feedback for anyone pondering a purchase.

May I first start by saying that I drive my car fairly hard on track days but by no means would I consider myself a fantastic driver. In honesty, I have trouble being able to really tell the difference between various sway bar and suspension settings, tyre pressures etc. I tend to check the tyres before I go out and then drive it like I stole it. My Kahunas aren't big enough to take corner one at the speed I think it should be taken at.

The 4WD Controller allows you to store and use (through a toggle switch) 2 separate "maps". These maps are variations on the way the car normally responds to the signals coming from the G sensor. Because you have so much variation, it is somewhat overwhelming as to what maps to use.

I started with an aggressive 4WD map (map 1) and a map which is slightly more aggressive than the way the car reacts as normal (map 2). I perhaps wasn't using the toggle switch as much as I should because once I had started driving the car with the system using map 1, I got so used to it, and liked it, so much that I didn't want to play with the toggle.

The car still switched between 2 wheel and 4 wheel mode, but it switches to 4WD so early and seamlessly that you don't even feel the transfer. Corners, both low and high speed, became (for me) much more controllable. I used to come onto the straight in 3rd gear feathering the throttle to maintain boost, basically steering with the back wheels. Now you can come onto the straight in a full 4 wheel power slide and you can "feel" exactly what the car is doing.

As it turned out I shaved a second off my times for the Clubman and National Circuits. Admittedly I changed back to a tyre I preferred, but I am sure I can keep the times coming down.

As an overview, so far as the controller goes - I'm wrapped. I still have a fair bit of mucking around to do to really get to know it but the level of 4WD control is awesome. Whilst I can't drift my car, I can pull off some awesome power slides at the moment.

If you are looking at a 4WD Controller for your car, DEFINITELY consider the Ruzic Engineering unit. You are more than welcome to check out the quality of the unit in my car."

Ed a.k.a 'EdGTR'

"Just a quick run down of my experience with the Torque Split Controller. I own a R32 GTR that is quite standard it only has an Apexi Power FC, adjustable camber and castor arms and a cat back and of course the TSC (Torque Split Controller). I took my car down to Wakefield for the Australia day track day with the auto sports guys and had a great time. I only just got my car ready for the day because i had a minor front ender in it a week before Christmas and it took a while to get all the parts sorted, but we got there even with a left hand front shock that by half day had leaked all its oil out and really had a lot of trouble keeping the wheel on the ground. The shocks and springs all look original so they have done ok being 17 years old, they will be changed very soon.

OK so to the TSC because that’s what you will be here to read about. First session out I took it easy after getting the Power FC tuned and a totally different wheel alignment done a couple of days earlier. But i found that the car really wanted to slide out of corners. The rear diff is also getting quite worn which was letting the inside rear wheel spin which really didn’t help with getting the power down. About halfway through the first session (4 to 5 laps) I didn’t like how it felt and wasn’t getting the power down all that well so i changed the TSC from standard (map 1 no gain) to map 2 and 10% gain and the difference was huge! Being able the get on the gas earlier and a lot harder it really changed to feel of the car. It felt and was a lot faster through the tighter corners where before I really had to pedal it, now I could just accelerate out of the corner. Through changing the drive to the front it held a tighter line by feeding the power to the front earlier and also helped with mid corner turn in.

I left it at this setting and thought that I needed to learn the track and get my lines a bit sorted. Later on in the day I started playing with the gain looking for the best exit out of the last corner onto the straight. I didn’t get a chance to play with the other maps but found that just on map 2 I was able to tune everything from power on under steer due to the front wheels breaking traction to nice smooth neutral over steer just by adjusting the gain. The biggest thing I found was that it made the car a lot easier to drive faster on the track.

I’ll be heading to eastern creek in a couple of months with coil-overs and am really looking forward to seeing what it can do around corner 1.

Ben a.k.a. 'BenR32'

This is yet another testimonial to the great gadget that is Paul’s GTR torque controller. I have had mine in my car for about 4 months, and I can honestly say that it has been the biggest handling upgrade I could have made. It is particularly useful in setting up the car for the conditions on the day, with a recent wet track day demonstrating it nicely. I was able to dial up sufficient RWD to get some oversteer into the corner, then at the apex when the g-forces really started kicking in there was enough FWD to pull the nose out of the corner and set it up nicely for the next one. Result? Controlled 4 wheel drift with the nose pointing the right way. And this was by no means working at the limit of the controller.

Its nice to be able to see the amount of drive going to the wheels in a real time digital display, as it means that you can dial the drive FW or RW to change the angle you reach at apex, and get the neatest and therefore fastest corner your car can handle.

I tend to be a minimalist in my cars interior, and although I know lots of people like to mount their controlled above the central air vents, I have mounted mine just left of the wheel on top of the digital clock. Sits there nicely, easily accessible for me and I don’t have to shift my eyes too much to see what its doing. All in all, if you haven’t already improved your GTR with one of these, you should. See you at track day!