Bainzy Posted September 29, 2013 Share Posted September 29, 2013 Having never dropped the differential, I'm not that familiar with it (aside from lying underneath it to top it up with oil) and have never examined the casing or looked inside. At some point in the future I need to mount a bracket on the diff to add a hall effect sensor, in order to 'sense' the four bolt heads where the output shafts meet the halfshafts. That'll give me a rear wheel speed signal for traction control, recording vehicle speed, mpg etc.Are there any locations on the casing that would be suitable for drilling, tapping and mounting a solid bracket, or would you perhaps recommend a different way of fixing said bracket? Quote Link to comment Share on other sites More sharing options...
black_rover Posted September 29, 2013 Share Posted September 29, 2013 I'd go for trying to mount the bracket using the bolts that hold the two parts of the diff together, it'd need some strengthening to keep it steady though. Unfortunately there is probably not enough space to mount it on the half shaft output housings.You could drill and tap into the flattish area above the half shaft output housings. Quote Link to comment Share on other sites More sharing options...
Bainzy Posted September 29, 2013 Author Share Posted September 29, 2013 Nice! Not sure using the propshaft flange would work for detecting wheelspin? Need to get my head round how the traction control would work. Definitely would work well for a VSS for detecting gears, mileage and fuel economy though.Looking at that photo it seems the flat about the output shaft would be wide enough to hold something sturdy-ish...Dropping the diff would be a good opportunity to not only this, but also drill out a hole and tap it for a drain plug, polybush it and finally swap my 3/4" lowering block for a 1" one.Is taking the diff apart to clean out any swarf a good idea and within the scope of DIY, or would I need to be able to set tolerances and know what I'm doing with it when putting it back together? Quote Link to comment Share on other sites More sharing options...
Clive Posted September 29, 2013 Share Posted September 29, 2013 Taking the output shafts off can be a challenge, requires a decent Allen key and extension. Once they are off, it is just a dozen bolts and the rear casing will be off. Nothing special required. Quote Link to comment Share on other sites More sharing options...
black_rover Posted September 29, 2013 Share Posted September 29, 2013 1381 wrote:Nice! Not sure using the propshaft flange would work for detecting wheelspin?...The sensor in that image is for my speedo, just happened to be the easiest image I had to hand. Quote Link to comment Share on other sites More sharing options...
GT6 M Posted September 29, 2013 Share Posted September 29, 2013 cliftyhanger wrote:Taking the output shafts off can be a challenge, requires a decent Allen key and extension. Once they are off, it is just a dozen bolts and the rear casing will be off. Nothing special required. Errr no quite reet Clive, but near.the rear case is a tight fit into carrier,and some times they can be quite stiff to shiftI hang em in vice and prise an wack wid lead hammer, the weight of diff bottomhelps to pull em apart.M Quote Link to comment Share on other sites More sharing options...
That Man Posted September 30, 2013 Share Posted September 30, 2013 Would it not be possible to fit some thing under the bearing carrier bolts? not sure how much clearance there is between them and the driveshaft bolt heads, You would only need a couple of millimeters for a bracket.I assume you're fitting a sensor both sides of the diff or you'll only be detecting wheel spin on one side Quote Link to comment Share on other sites More sharing options...
junkuser Posted September 30, 2013 Share Posted September 30, 2013 Is this traction control system of the type that controls braking to the individual wheel that spins or slows inappropriately or simply one that controls engine power output when a drive wheel spins up? Quote Link to comment Share on other sites More sharing options...
Bainzy Posted October 1, 2013 Author Share Posted October 1, 2013 Junkuser - the latter. It'd have to have some pretty advanced braking capability to do the former, it's just going to be spark/fuel cut. The MS3 ECU is geared to do it out of the box, all I need to do is give it a front wheel and a back wheel sensor.I'm not sure whether I need do install it on both driven wheels, though I guess it'd be a better installation if done on both sides. The code for Megasquirt traction control is only designed to take 2 wheel speed inputs at present (ie 1 front + 1 back wheel), although the software is in constant development so that could expand to 4. If I used a Racelogic system, that would have 4 inputs.Off the top of my head obviously it would work with just one driven wheel in a straight line, like a launch control, as slip would make the back wheel speed compared to the front wheel different. Not sure how it would work in cornering though as wheelspin would be uneven between the back wheels but people seem to have it working, so need to investigate a bit further as to why that actually works. Quote Link to comment Share on other sites More sharing options...
junkuser Posted October 1, 2013 Share Posted October 1, 2013 With that type, the information from a trigger wheel on the pinion shaft of the diff should suffice if you can make adjustments for the differing rates of signal input between wheel rotation on the front wheel and pinion rotation.Maybe you could fit trigger wheels with same ratio as diff if it can't be done in the software.An advantage of sensing from the pinion is that it will accelerate more rapidly than wheel rotation due to the diff ratio and will detect whichever drive wheel spins is how I see it Bainzy. Quote Link to comment Share on other sites More sharing options...
Bainzy Posted October 2, 2013 Author Share Posted October 2, 2013 Interesting, thanks for the input! Perhaps Steve's speedo setup might be the way forward then? Certainly looks an easier method of installing a sensor anyway. Quote Link to comment Share on other sites More sharing options...
junkuser Posted October 2, 2013 Share Posted October 2, 2013 Would be interesting to get input from others to check I am getting this wrong though Bainzy.With an input from pinion, like Steve has done, you could also fit a sensor for a speedo and one for a cruise control, What fun!An anti-theft device, fed from this, that cut the ignition, would frustrate a thief. Able to start the car, only to find it repeatedly stalled each time he tried to move off. I wonder how long a thief would persist. :) Quote Link to comment Share on other sites More sharing options...
Bainzy Posted October 2, 2013 Author Share Posted October 2, 2013 Some good news junkuser, I think it would now work with the MS3 code: http://www.msextra.com/forums/viewtopic.php?f=131&t=51591One of the things I love about Megasquirt is how it's always in development. Really glad I went for MS3 as that's where all the energy is being put into making improvements. One thing I'm looking forward to trying with the latest updates is a progressive overrun fuelcut return, as the way it works currently can feel a bit jerky sometimes. I also want to get around to trying knock sensing, I just need to figure out where I'd be able to mount a sensor on the 1500 block. Quote Link to comment Share on other sites More sharing options...
junkuser Posted October 2, 2013 Share Posted October 2, 2013 Good news indeed Bainzy.I'm strictly mechanical, electronics I leave to others, but it sounds as though you have abilities in in the area so looking forward to postings on a successful outcome. Quote Link to comment Share on other sites More sharing options...
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