When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Anyone ever made their own reluctor wheel for a wheel/driveshaft speed sensor? I whipped something up real quick on my car for a front wheel speed sensor and the spacing between pickups isn't perfect. There is maybe .100 variance between any two posts. It was the best I could do. I'm curious if anyone knows if the different pick points will render this completely useless? The pickups are the bolts I between rotor and lugs.
The difference in spacing will effect the signal. Will it be enough to cause a problem? I can't say. I can say that a cracked reluctor ring on a drive axle will cause the ABS to kick on at low speeds. Now these rings are about 3.5" in diameter and have about 30 teeth. So take that for what it's worth.
And the teeth and grooves are about .200" and a crack is about .030".
Last edited by Bad Apache; Apr 19, 2016 at 08:26 PM.
If one is good than 8 has got to be even better. Take note that I'm using this for traction control and not vehicle speed.
With that said what sensor did you use? Do you know if it will work without a magnet?
1 would offer very poor resolution for traction control...although I guess a lot also depends exactly how good the TC system you're using is. I'd say 4 teeth as a minimum though
Looks like your discs bolt to the rear of the driving flange ? Can you access the heads of those bolts ?
But your setup should work ok, I'd always prefer to have the trigger wheel on the inside of the hub, not the outside where yours looks to be. Mainly as it's easier to keep the sensor wiring away from harms way and heat.
The difference in spacing will effect the signal. Will it be enough to cause a problem? I can't say. I can say that a cracked reluctor ring on a drive axle will cause the ABS to kick on at low speeds. Now these rings are about 3.5" in diameter and have about 30 teeth. So take that for what it's worth.
And the teeth and grooves are about .200" and a crack is about .030".
You can buy ABS rings in many shapes and sizes, and tooth counts. From a safety perspective though it's critical their wheels are in perfect shape and symmetry or the system will just not work correctly
Whether odd spacing matters too much will also depend how many teeth it registers before accepting the signal. Some may accept every tooth, some may accept an average of every 4 teeth, 8, whatever. So depends on the system and how configurable or not it is
1 would offer very poor resolution for traction control...although I guess a lot also depends exactly how good the TC system you're using is. I'd say 4 teeth as a minimum though
Looks like your discs bolt to the rear of the driving flange ? Can you access the heads of those bolts ?
But your setup should work ok, I'd always prefer to have the trigger wheel on the inside of the hub, not the outside where yours looks to be. Mainly as it's easier to keep the sensor wiring away from harms way and heat.
Studs are not accessible to pick up off of with out pulling of the dust shield. I'm going to try and avoid that for now. I will making a custom bracket to hold everything and keep it away from heat. It will be interesting to see what happens.
More will give finer signal to work better with on TC for sure. Scott Clark suggested 12 as a perfect number on the fast back I’m working on. If they aren’t spaced exactly I’d think you’d have an less than square (ugly) signal. I’d think the pulses should be exactly spaced to work properly and give a clear signal… but that’s just a guess.
If using 2 sensors when drag racing TC isn’t usually turned on until 1-2 seconds (or however long it takes the front wheels to come down.) into the run. By that time you’re doing well over 60mph. And getting quite a few pulses to work with. I agree 1 tooth isn’t optimal, but you wouldn’t have to worry about spacing the teeth perfectly.Matt has proven with his 1 tooth screw driver pickup it works to some degree anyway.
I know Clark was using just the driveshaft VSS and basing it off a perfect run RPM VS VSS MAP to eliminate the FWD wheel sensor and allow TC from the get go. Might be another option for you instead of playing with un-driven wheel speed.
1 tooth would offer almost no resolution, and be far slower to respond for it to actually recognise changes in wheel speed
Although given he's using the Holley system which needs the Davis to work TC....do they not use a reference from driveshaft speed only as Force is saying ?
1 tooth would offer almost no resolution, and be far slower to respond for it to actually recognise changes in wheel speed
Although given he's using the Holley system which needs the Davis to work TC....do they not use a reference from driveshaft speed only as Force is saying ?
How would you figure the pulses based on teeth? Site online says a 25” tire has a 78.5” roll out and rotates 840 times per mile.
So…210 revolutions per ¼? Or 210 pulses with a 1 tooth wheel? That can’t be right. My MPH seems to react pretty quickly. I’ll check the logs to see what kind of speed changes register per MS.
More will give finer signal to work better with on TC for sure. Scott Clark suggested 12 as a perfect number on the fast back I’m working on. If they aren’t spaced exactly I’d think you’d have an less than square (ugly) signal. I’d think the pulses should be exactly spaced to work properly and give a clear signal… but that’s just a guess.
If using 2 sensors when drag racing TC isn’t usually turned on until 1-2 seconds (or however long it takes the front wheels to come down.) into the run. By that time you’re doing well over 60mph. And getting quite a few pulses to work with. I agree 1 tooth isn’t optimal, but you wouldn’t have to worry about spacing the teeth perfectly.Matt has proven with his 1 tooth screw driver pickup it works to some degree anyway.
I know Clark was using just the driveshaft VSS and basing it off a perfect run RPM VS VSS MAP to eliminate the FWD wheel sensor and allow TC from the get go. Might be another option for you instead of playing with un-driven wheel speed.
I am using front vs. rear wheel speed. luckily my car squats and goes (1.32 60') with no wheel hang so im hoping to use it on the launch as well. For now it is going to be used at this roll race i have coming up. I agree that the teeth need to be perfect spaced to get a clear view. However I don't think i will have a huge issue since they are not that bad.
How would you figure the pulses based on teeth? Site online says a 25” tire has a 78.5” roll out and rotates 840 times per mile.
So…210 revolutions per ¼? Or 210 pulses with a 1 tooth wheel? That can’t be right. My MPH seems to react pretty quickly. I’ll check the logs to see what kind of speed changes register per MS.
Not 100% on the specifics as a friend of mine has figured that part out. For now (until i see tables) i can tell you we are telling it how many teeth per revolution and tire diameter.
If you want accurate readings, drive along with a good GPS unit then you can adjust the circumference setting until they read accurately.
And under power, driven wheel speed tends to go higher than undriven, up to maybe 4-5% or so in some cases but it is not wheelspin. Even with tyres that are definitely not deforming...bit weird that
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Slideshow: From wobbling harmonic balancers to failed EBCMs, these are the issues that define long-term C5 ownership and what repairs typically involve.
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Slideshow: A modern Camaro transformed into a retro icon, this limited-run "Bandit" build blends nostalgia with brute force in a way few revivals manage.
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Slideshow: Cadillac didn't just crash the high-performance luxury vehicle party, it showed up loud, supercharged, and occasionally a little unhinged...
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Slideshow: A one-off sports car that looks like a vintage Italian exotic-but hides a C6 Corvette underneath-just sold for the price of a new mid-engine Corvette.
Homemade reluctor wheel 
