Liv2race

Hi,

I'm looking to build a monster miata. With the v8 I would love abs. Is it practical to keep from a $ stand point? or even possible?

I'm currently looking for a car and I'm winding if I should go through the trouble of finding a abs car.

Thanks.

tbone heller

Personally, I would ditch the ABS & upgrade to a big brake kit.

Liv2race

The abs won't work well with the BBK?

tbone heller

Sure it will. I was just saying that I feel as though a brake upgrade is needed when doubling (quadrupling in my case) the stock horsepower on a Miata. The ABS would be a personal preference. I, myself , would prefer a car without ABS so I did not have to deal with the rear exciter rings as well as all of the ABS control valve stuff occupying valuable under hood space. My car stops well without it. Hopefully somebody with ABS will respond. Jason (MRM331) has done 4 conversions. Maybe one of those was on an ABS car.

Liv2race

Thanks for the replys. I do plan on road course and autox with this car. So I was figuring if a 2500lbs car with 400hp and 225 tires in the front (biggest I can tell can fit on a miata from my homework) that abs would be nice.

MRM331

ABS is pretty easy to keep. To do so you need to make sure you get a 7.5 rear and half shafts from a T-bird that had ABS as opposed to one that does not. The diff on a ABS Thunderbird will have a machined surface to which you can mount the Miata ABS sensors using some aluminum angle stock. The Miata sensors will read the Thunderbird's inboard-mounted exciter rings fine if you can line everything up precisely. To get the length out of the rear ABS sensor wires you'll need to move them inboard you'll have to remove the stamped steel supports from the wires and reroute them up out of the way of the exhaust and half shafts.

My current car is using a non-ABS rear and I can't get the sensors square to the rings. Once I get it working witht eh right diff I'm going to add an "off" switch to my switch panel so I can deactivate it on the track (unless it's raining).

The second build I did (93 LE) has the ABS working fine with the correct diff.

Here's the brackets you'll have to make:



Here they are mounted up:



more here:

http://www.cardomain.com/ride/312971...zda-miata-mx-5

-Jason

Liv2race

That's awesome! It's that simple?! The thunderbird half shafts have the exact number riges on the tone ring as the miata does?

MRM331

It doesn't matter. All the ABS computer is looking for is movement vs. no movement (which it sees as "pulses" vs. "no pulses"). The actual number of cogs does not matter unless you're using it to run a traction control system (which I'm going to attempt as soon as the software for the MS3 is avaiable).

-Jason

Liv2race

Sweet. Is the miata 90-95 obd1 cars 3 channel or 4?

MRM331

Only 3.

Liv2race

Thanks everyone!

Keith

Just an update on a long-ago post - this isn't quite correct. The ABS is comparing the rate of pulses front and rear, and if you get the wrong number of teeth it will trigger the ABS early. We once had a Mazdaspeed on track with staggered tire diameters (don't ask), and it would trigger ABS really easily thanks to the change in rotational speeds front and rear. So while the ABS continued to work, it wasn't working properly. We squared up the tire sizing, problem went away.

MRM331

Update on an update:

The customer I built the car for is more than happy with his ABS-equipped '93LE Ford V8 Miata and has had no issues with the ABS kicking in too early. He's driven it over 10K miles since the build and has tracked it as well. He's running 225/45-15 RS3's all around (23" diameter tire) with Miata ABS rings on the front and 1996 Ford Thunderbird ones on the rear. He has upgraded to 1994-spec rotors and calipers all around and runs Axxis Ultimate pads.

Perhaps the extreme stagger you ran affected the front/rear grip or weight bias of the car causing the strange braking issues you experienced. There are a lot of other possible reasons other than an ABS-tooth issue for your experience, especially considering the lack of any issues my builds have had regarding this area.

-Jason

Keith

I'm glad to hear he's happy.

This problem on our car showed up on the track. Changing nothing more than the tire diameter up front delayed the onset of ABS without making any change in weight bias. It was a pretty controlled test, and it wasn't an extreme stagger. It's possible that someone who wasn't used to Miata braking on track wouldn't have noticed the early ABS onset.

MRM331

I think Keith that we'll have to put this in the "agree to disagree" pile you and I have sort of been creating along with "proper hood pin locations" and "overall LSx vs. Ford build costs".

Differences of opinion are responsible, after all, for most of the advances of mankind

-Jason