SAAS S-DRIVE Throttle Controller Part 2 – The verdict

In the June 2020 issue of NZ4WD I wrote about us acquiring an SAAS S-Drive unit to fit to my 2003 Range Rover V8.  Initially I had a problem working out how to access the wiring plug on the luxury Range Rovers ‘organ’ type accelerator pedal but once I found out how to remove the pedal it was literally a two-minute job... only for the wiring plugs to be different. 

 

BMW vs Ford 

I went back to North Island importer Warren at 4WDbits, sending him photos of the unit and the wiring plugs.  It was baffling as the unit supplied was the correct unit for that model Range Rover. However, Warren was the one quick enough to identify the wiring plugs as BMW and considering the Range Rover had the BMW V8 engine and the accelerator pedal actually had the BMW logo and numbering on it, we tried a BMW unit and it fitted.  

All we can think of is that Land Rover fitted the BMW engine for the first couple of years then changed to the Jaguar engine under Ford’s ownership and possibly also changed the wiring plugs at the same time. 

It took all of a few minutes to plug the unit in and refit the pedal and run the wiring up to the dash for the small S-Drive display controller. The display has a sticky pad on the back so once you know the exact location you can stick it to the dash. 

 

Set ‘n forget!

Once fitted the first thing to do once turning the key is to set the transmission type (to automatic or manual) by holding the mode button for three seconds (as per the instructions). And do you know what?  

No sooner than I had started the engine I immediately noticed an instant improvement in throttle response while it was still sitting in the garage.  It was like the engine had suddenly woken from a long period of hibernation. 

 

Five of the best

The five modes are; Comfortable, Sport, Racing, Eco Fuel saving, and Normal (factory settings) and – believe me - there is a considerably noticeable difference between Normal and say Sports mode.  Taking it for the first drive up the road was exhilarating. I always considered that the V8 had very good acceleration, especially using the tiptronic sports mode in the gearbox but with the S-Drive it was a completely different vehicle.  

Standing starts at intersections had the tyres chirping, not normally associated with a 2.4 ton permanent 4WD vehicle. In sports mode the throttle was very positive and responded to the slightest touch.  

Like a kid in the candy store, I kept playing with the throttle feeling the instant response but quickly limited the use of race mode. After all the manufacturers purposely build in that ‘lag’ to give longevity to the vehicle. 

 

Eliminating throttle ‘lag’

If anything, in fact, fitting the S-Drive highlighted how much ‘lag’ vehicle manufacturers tend to tune-in for smooth throttle responses to minimise strain on the vehicle. This ‘lag’ is the delay from the moment the accelerator pedal is pressed, to the time the signal gets to the throttle, and the S-Drive has eliminated it almost completely depending on mode setting.

In saying that the system also works ‘the other way’ when you are off- road because you can get better throttle control on rough tracks by selecting the eco mode which gives a slower response and smoother acceleration.  

We have all been there when the foot bounces on and off the accelerator on rutted tracks and eco mode gives you more throttle control thanks to the dulling of pedal input.

 

Big tick for ‘real world’ use!

For a real world drive a day journey of around 370kms was undertaken which included highway, city driving and country roads.  Trying to pull out from my typically ‘quiet country road’ onto an extremely busy state highway means you need to be quick off the mark so in preparation I selected sport mode and instantly the throttle response changed. 

Once on the highway I then tried various different settings including the economy mode.  This gives a longer pedal by reducing voltages and input. Initially I didn’t like the seeming longer pedal and switched back to comfort mode for the 1.5 hour trip.  It proved very easy to maintain a set speed all the way and any passing was done quickly and safely.  

The accelerator pedal even feels lighter and didn’t seem so tiring on the foot on the longer journey.  

 

Fuel consumption

I had reset the on board fuel consumption computer as I left  and on a trip which included the stop start of peak hour traffic in East Auckland and the Southern Motorway consumption rose from 11.6L/100kms to 13.3L/100kms.

Once clear of that though I changed to economy mode for the trip home and the average consumption figures dropped to 12.5L/100kms by the time I got home.  Of course any potential fuel savings can quickly be eroded with excessive use of the throttle in sport and/or race modes and I have yet to get over the enjoyment of better acceleration!

With the WoF due I booked the Rangey into the garage and the proprietor Karl, who had done previous WoFs and thus driven the vehicle, also commented about how impressive the S-Drive was and the improvement it had made. 

 

Like night & day!

The S-Drive doesn’t provide any additional power or torque but it certainly feels like it with the faster throttle response, even in Comfort mode.  Putting it back to normal or factory mode almost feels as though it the vehicle is in limp mode, such is the difference; It’s like night and day. 

And going back to the Land Rover Discovery 3 (also 4.4L V8), well, it almost seems lethargic in comparison. 

While the S-Drive doesn’t provide any additional power to the engine, the quicker responses from the accelerator pedal can mean slightly quicker 0-100km/h acceleration times. Using an acceleration timer app on my mobile phone I did several runs through the various modes including Eco Fuel saving.  The app would start once the vehicle moved and gave the 0-100km/h time which seemed to be around 110km/h on the speedo. With times ranging from 8.00 seconds in race mode to 10.01 in Eco mode there was a slight improvement over factory mode of 10.85 by around a second. In race mode I got 9.01 on the metal and tried it again on tarseal near home and got 8.01 so I was probably losing a little bit with breaking traction on the standing start.  Certainly the traction control light indicated lack of traction at the start each time but it was the same for all runs. So overall on average 0-100km/h times were improved by close to a second. 

I have yet to do any real towing since fitting the S-Drive but already know the S-Drive will be a huge benefit when doing so with better acceleration under load. 

 

More than impressed!

I am enormously surprised and very pleased at how much of a difference a simple unit like the S-Drive can make to the driveability of a vehicle, especially one that is already powered by a V8.  The benefits I’d imagine on a common rail diesel Ute would be far greater and at $230 RRP it is a very cheap and good investment.