S6 traction control on r33 gtr

[Daniel a]

Hi all

I've been chatting to romain about fitting traction control to my r33 gtr, romain has suggested to fit the gps module to get the best launch out of my setup. Basically I'm only after tc for launch at the strip, now I've read this can also be used reading the abs sensors so is gps module a must or can the s6 run traction control with the abs sensors on a r33 gtr?

Thanks
Dan

[pavlo]

No the GPS is not the way to go on an R33 gtr.

You only need one good speed input to get launch working to a good level using the Launch hold timer.

If you have a very rwd bias car then front and rear speed sensors are an option, the GTR ABS sensors are bipolar and you will have 4 spare inputs on the GTR (as cam and crank are termistor) then you can use full launch and TC on the S6.

GPS is not reliable enough IMHO, but can be useful if you have no other inputs spare, even if you did use the GPS You can just use the time from a moving speed.

[Daniel a]

I think the idea for the gps sensor was for the built in g sensor?

So traction control can actually be set up using the abs sensors, I though this would be the case because the front wheels only get 30%power maximum or so I've been told.

Can I pick up abs sensors from the abs unit and run to the ecu? Will I need to have all 4 or just 1back and 1 front? I have a cas kit on mine and crank and can sensors go to the k plug

Thanks
Dan

[pavlo]

You can get away with just one front and one rear, especially if the rear diff is quite tight. But really if you want TC for circuit use then all 4 is preferred as you can average speed across an axle.

If it's for drag use and launch only, then only one front wheel speed is required as you regulate RPM vs wheel speed, or trigger a timer when the speed exceeds say 3mph and then ramp up the RPM limit with time.

Why don't you explain exactly what you want, and then we cant tell you the best way to achieve it?

cheers

Paul

[Daniel a]

Hi Paul

I'm after the simplest way to get the best launch possible, and I think traction control is the best way of achieving that specially considering I can the run what ever tyres I like and should allways get the perfect launch with out to much messing about with launch control at the track.

Why I'm at it I might aswell run all 4 abs sensors, we're the best place to pick these up from on the 33 gtr would you say?

I read a few post from Ryan about tapping into one side of the sensor and also then the abs and attesa system will still work is that correct?

Thanks for your reply Paul

Dan

[pavlo]

If it's only launch then TC is not the best way to do it, that's not what it's designed for. If you always want the perfect launch then you will always have some messing about to do. TC typically is used after launch control has been exited.

You're simplest route is tap into 1 wheel speed sensor on the front axle, the ABS and Attessa should still work just fine. If you generally spin the rear wheels and not all 4 then this will give you a setup that can regulate engine RPM based on front wheel speed, and if there is less grip it will still work it will just take longer to get up to speed.

If you have the spare inputs then a a rear wheel sensor, and if you have lots of spares, add all 4 wheel speeds then you have all options covered. I think the sensors end up in the Attessa unit and the abs module.

Cheers

Paul

[Daniel a]

I understand what your saying Paul, initial launch is actually really good but the power seems to come in a bit hard and the wheels start spinning so that's the part I'm trying to improve.

Il have another word with romain and get all the wiring sorted for abs sensors ready for when he maps the car on flex fuel as I'm planing to go back to santa pod on the 23rd August

Thanks again paul

[pavlo]

Launch control will usually run out to the end of 1st gear.

2nd gear onwards will definitely be TC related but for TC to work you need a rear wheel sensor (or two) to measure the drive wheel speed and while you can compare that against GPS speed from the Syvecs GPS box it't not fast enough from a standing start sometimes. There are other boxes like the Racelogic SPeedbox that gives an accelerometer corrected GPS speed pulse output you can use which is better. Normally you add a speed sensor onto the undriven wheel, which on a GTR is not so clear cut, but if you're mainly spinning the rears it should be a good start.

[stevieturbo]

Paul, have you ever encountered what some of the US guys use for traction control ?

ie Davis traction control ?

Whilst primarily aimed at 2wd/rwd cars, they monitor propshaft speed and base everything around that. they map out, record/learn the fastest prop speed ramp vs time and if there is a fast deviation above this ramp, it is considered as slip and a controlling action can take place.

They claim it is patented technology, mostly sold as complete systems, but for the Holley ecu they offer a cheaper unit that sends feedback to the ecu so it can reduce power based on it's input.

Crude in some ways, but they deem it very effective for drag use. Not sure if it would ever marry up with the Syvecs though...or if they could use a similar approach ?

If they could, it would negate need for multiple wheel speed sensors and gps info.

I can see how it would work for drag racing...road or track...not so much

[Daniel a]

Launch control will usually run out to the end of 1st gear.

2nd gear onwards will definitely be TC related but for TC to work you need a rear wheel sensor (or two) to measure the drive wheel speed and while you can compare that against GPS speed from the Syvecs GPS box it't not fast enough from a standing start sometimes. There are other boxes like the Racelogic SPeedbox that gives an accelerometer corrected GPS speed pulse output you can use which is better. Normally you add a speed sensor onto the undriven wheel, which on a GTR is not so clear cut, but if you're mainly spinning the rears it should be a good start.

I don't have any problems in second gear paul it's all first, what do you think is the best way to approach this Paul would you say?

Is it also possible to control 4wd system on the s6 so I have full 4wd off the line instead of waiting for rears to spin then transferring power to front?

Thanks
Dan