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The nb6c has a.b.s brakes standard. Rick (racing partner) says get rid of them and other people say to keep them. I am not sure which way to go. It might be a hassle wiring it up to after market computer. I like the idea of just standing on the brakes and turning. The brakes on my na are very tricky and sensitive to locking the fronts. In saying that, i can stop very quick compared to other cars, i just back off slightly when it starts to lock the fronts.

lightyear wrote:The nb6c has a.b.s brakes standard. Rick (racing partner) says get rid of them and other people say to keep them. I am not sure which way to go. It might be a hassle wiring it up to after market computer. I like the idea of just standing on the brakes and turning. The brakes on my na are very tricky and sensitive to locking the fronts. In saying that, i can stop very quick compared to other cars, i just back off slightly when it starts to lock the fronts.

If it is the same as the Oz spec NB8B on cars, the electronics are in the unit. Only need to keep the wiring from the wheel sensors, and a couple of others. I have also seen another setup where the ABS has its own computer in the footwell, that was on a 2000 JDM NB8.

The old guard will tell you to throw it away. True, with a properly set up brake package, you can theoretically get 100% efficiency out of all four wheels. Theoretically. But I challenge anyone to consistently get 100%, every time, every corner, every track condition, as tyres wear and oil, rubber and rain changes grip levels. And you only need one brake lockup to flat spot a (pair/set of) tyres.

Best of both worlds - put in a proportioning valve, dial it up so the rears lock just a smidgeon before the front (pull the fuse on the ABS to set this up). That way you will get a theoretical 95-98% efficiency before the ABS starts pulsing and maybe unsettling one end or the other, and be able to get that every time. Actually you will be doing better than that, because if you have to lift off the brakes because one wheel is locking, you are lifting for all. With the ABS one wheel may be pulsing, but the others are at max pressure (unless you have jumped on them so hard all wheels are pulsing - I am assuming an intelligent driver here obviously). I would expect this to come into its own in the rain.

BTW, AFAIK the NB ABS are all three channel - that is one each for the front wheels, and one for the rear. This means that either rear wheel can signal the ABS unit about an imminent lockup, but the unit will pulse both rears.

loose it...

The only other reason i might get rid of it is the added weight. I figured it would be slightly less brake force but be more consistent. When i strip the car i will see how much weight it looks like there is in the set up, if i think it's too heavy it's gone. Every kilo counts.

project.r.racing wrote:loose it...

because .... ?

Well me and Irwin have taken turns driving mine and his car in the wakefield 300 enduro(150km's each). That's a non-ABS NB8A with a proportioning valve Vs an NB8B with one. Remember it's not just ABS, it's also EBD (Electronic Brake Force distribution), so as pads wear thinner or you change compounds it keeps the balance without manual adjustment. Biggest difference I noticed was trail braking though, the inside rear wheel of Irwin's always wants to lift on the fishhook at wakefield park which makes it very twitchy as just that wheel locks with a soft application of the brake. It's also a brilliant guard against flat spotting ... Race tyres are far too expensive to ruin so suddenly.

I am thinking of running it, i can always take it off after if it doesn't work out. It will be good to do a comparison, as both cars will be identical other than the a.b.s.

lightyear wrote:I am thinking of running it, i can always take it off after if it doesn't work out. It will be good to do a comparison, as both cars will be identical other than the a.b.s.

Better still, sort the car with ABS, get enough seat time to get down to consistently fast laps, then do 5 laps with the ABS on, then pull the fuse, and do another 5 laps (not changing anything else - ie back-to-back test). Then evaluate the lap times, and the handling characteristics. I'd love to hear the result.

Doing a comparison between different cars, one with and one without, may be indicative but is certainly not definitive.

I wil do that. Keep you posted. But, they won't be ready for about 6 months. They are getting the cages next week at meridian motorsport.

I thought you needed power to the ABS unit to open the lines to the brakes. There's a reason you need the ignition on to bleed an NB8B. So I don't think you can do easy back to back tests like that.

Hellmun wrote:I thought you needed power to the ABS unit to open the lines to the brakes. There's a reason you need the ignition on to bleed an NB8B. So I don't think you can do easy back to back tests like that.

I am almost absolutely sure that the brakes on an ABS car work with no power - the mind boggles at an abs car not stopping because power failed, they are designed to be fail-safe. Happy to be corrected though (well, not really happy, I don't think I want to know that an electric problem will affect my brakes!).

Hellmun wrote:I thought you needed power to the ABS unit to open the lines to the brakes. There's a reason you need the ignition on to bleed an NB8B. So I don't think you can do easy back to back tests like that.

I have fitted a switch to the dash of the Rally car that turns the ABS on and off
I turn if off in Stage and the brakes work. Mind you the front rear split is bias to the rear.

Well I figured you still got some brakes but it's probaly just a default setting that's hardly going to be a fair comparison. I wouldve guessed it'd be a front bias setting instead of rear though.

greenMachine wrote:

project.r.racing wrote:loose it...

because .... ?

cos for a race car, it uses/controls braking dynamics that are not required on a race car.

Definately have to keep the abs... Saves flat spotted tyres( we all know how much tyres cost)... Great for wet weather.

I'm looking at fitting abs to the green car soon.