thezguy Posted March 27, 2014 Share Posted March 27, 2014 (edited) Im about to order a Davis Traction control box for my S30. Im trying to figure out th eseast way to read drive shaft speed. Shannon davis has a loop mount and sensor to read the drive shaft speed but its a bit pricey. When rebuilding my diff a few months ago i noticed an ABS sensor? in the front of the short nose R200. The question i have is what exactly is this sensor reading? pinon flange speed? a reluctor wheel? how does it read it? does any one have detailed information on this. the davis box can be calulated to run just about any sensor so it would be nice to utilize what is already there. Edited March 27, 2014 by thezguy Quote Link to comment Share on other sites More sharing options...
RebekahsZ Posted March 27, 2014 Share Posted March 27, 2014 You want this why? Quote Link to comment Share on other sites More sharing options...
Domzs Posted March 27, 2014 Share Posted March 27, 2014 Agree ^^^ . Why ? Quote Link to comment Share on other sites More sharing options...
tube80z Posted March 27, 2014 Share Posted March 27, 2014 I could think of many reasons, can't you? Quote Link to comment Share on other sites More sharing options...
thezguy Posted March 27, 2014 Author Share Posted March 27, 2014 Why would I want traction control? Do I seriously have to awnser that question. 275 tire + 800hp + 2900lbs = ZERO traction Let's keep this on topic fellas does anyone have an idea? Quote Link to comment Share on other sites More sharing options...
roger280zx Posted March 27, 2014 Share Posted March 27, 2014 I'm sure there is a plethora of information on the abs system if you look in the right place. The origin of your r200 is where I would start searching. Quote Link to comment Share on other sites More sharing options...
thezguy Posted March 27, 2014 Author Share Posted March 27, 2014 (edited) Good point. Mind pointing me in the right direction? all the info ive run across is how to get rid of traction control and ABS. What im essentially looking for is the tooth count on the ABS ring for the short nose VLSD R200 Edited March 27, 2014 by thezguy Quote Link to comment Share on other sites More sharing options...
luigi Posted March 27, 2014 Share Posted March 27, 2014 what year, make and model is your diff? I may have one in the basement that I can look at or take apart. Or may be able to get my friend at the dealer to look and see. I'm going with the clamp on the driveshaft ring. I can't order until Monday. I think he's racing Quote Link to comment Share on other sites More sharing options...
thezguy Posted March 27, 2014 Author Share Posted March 27, 2014 I was told the Diff came from a 95 Q45.. I know it is the R200 VLSD short nose with the ABS sensor plugged into the right side of the diff if looking at it from the rear of the car. Quote Link to comment Share on other sites More sharing options...
luigi Posted March 27, 2014 Share Posted March 27, 2014 Oh.....ok, the sensor is actually reading the output shaft correct? Quote Link to comment Share on other sites More sharing options...
thezguy Posted March 27, 2014 Author Share Posted March 27, 2014 Yes, The parts fisch refers to it as the companion flange. If you have one lying around you can pull the sensor out and clearly see the ring gear for a count Quote Link to comment Share on other sites More sharing options...
socorob Posted March 27, 2014 Share Posted March 27, 2014 The front would be the input shaft, wouldn't it? My 2 early Q45 diffs had them on the input shafts on the front of the diff. My friends late one has them on both output shafts, 1 on each side of the diff. Quote Link to comment Share on other sites More sharing options...
We Bad Posted March 27, 2014 Share Posted March 27, 2014 If you haven't purchased the Davis box yet, you might want to look at the MSD ignition box #7531. It has traction control without the driveshaft pickup. (Of course it is illegal in most places as is the Davis box.) Quote Link to comment Share on other sites More sharing options...
socorob Posted March 28, 2014 Share Posted March 28, 2014 How does it work? Does it need an abs system and pump, or does it cut fuel, timing, or??? Quote Link to comment Share on other sites More sharing options...
We Bad Posted March 28, 2014 Share Posted March 28, 2014 Both the Davis and MSD units limit wheelspin by pulling timing from the engine. They look for a sudden increase or spike in rpm's that would occur when the tires break loose. The Davis unit sends a 12 volt signal to the engine's ignition box when a loss of traction is sensed (when the driveshaft rpm spikes). The ignition box handles the retard function. Most high-end ignition boxes have one or more retard circuits built in. These circuits are commonly used for backing off the timing when Nitrous Oxide is engaged or as a high speed retard when the car goes into high gear. The MSD unit senses a spike in engine rpm's. Since the engine acceleration is different depending on which gear the car is in, it has user adjustable settings for five different acceleration rates. The amount of timing retard is also user adjustable, as is the rate at which the timing is ramped back in. Quote Link to comment Share on other sites More sharing options...
luigi Posted March 28, 2014 Share Posted March 28, 2014 (edited) Can you not unbolt it and count the teeth? I'm guessing it's in the car right? I looked and didn't find 1 that has a sensor in the front. I think the ones I saw were all Z32 with 2 on the rear cover. When used with fuel injection, the Davis can pull fuel or manage a DBW throttle. As for the 7531, I've been around them, in my opinon, not a great solution for a street/road race car. Edited March 28, 2014 by luigi Quote Link to comment Share on other sites More sharing options...
thezguy Posted March 28, 2014 Author Share Posted March 28, 2014 (edited) Input shaft/companion flange are the same thing. Like I stated earlier the fisch calls it a companion flange. From my understanding the later model Diffs with the two sensors are actually wheel speed sensors vs. DS speed sensor like In the front. You do not need an ABS system. I am trying to utilize a pre existing way to measure DS speed (abs sensor/ring gear) that is already installed on my diff. Utilizing this sensor would prevent me from having to speed extra money and mounting hardware and sensors Edited March 28, 2014 by thezguy Quote Link to comment Share on other sites More sharing options...
thezguy Posted March 28, 2014 Author Share Posted March 28, 2014 I can count the teeth but the car is not in my possession at the moment. Quote Link to comment Share on other sites More sharing options...
thezguy Posted March 28, 2014 Author Share Posted March 28, 2014 (edited) The Davis box has the option the use any two forms of retardation together. Timing/boost/fuel/nitrous etc. I do like the idea of using the MSD box to cut timing based on RPM at certain "ranges" for the simplicity of it. However I more so like the idea of having live actual DS speed feeding the control box it just seems more to the point. From what I've been reading there are tons of ways to do accomplish TC such as wheel speed sensors/DS speed sensors/ timing retardation etc. Edited March 28, 2014 by thezguy Quote Link to comment Share on other sites More sharing options...
socorob Posted March 29, 2014 Share Posted March 29, 2014 Just went to the garage to count mine. You can't see the gear at all like you can on the side ones. You would have to pull out the VR sensor and get something in there to mark it (liquid paper?) and try to count it through the little hole. I guess it would have to be drained first or maybe if it was stood up it wouldn't lose oil. Quote Link to comment Share on other sites More sharing options...
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