What are you using for driveshaft RPM speed monitoring ?

[Beamer]

What are people using for driveshaft rotation monitoring? I am trying to figure out what to use and how/where to mount the components to monitor the RPMs of the driveshaft. I know there are magnets to attach to the driveshaft and some sort of a pickup to detect the magnets. Is there a way to mount them to the axle housing to pick up near the rear of the drive shaft, or is it capable to use an L bracket coming down from the body to sense the magnets?

Thanks in advance,
Mike

 

[bishir]

Can't this be figured out by doing some math?

 

[V8Assassin]

Mike,

Most of the guys I know of actually getting that info are using a driveshaft sensor hooked to their XFI. Not sure on the chip cars.

 

[chopped39]

They used to have a cruise control system that ran off the drive shaft years ago.Probably be better closer to the trans to minimize up and down movement.Something off the front yoke .Or if you have a driveshaft loop? You can mount the pickup to the loop. I like the way Pat Musi has his car set up.He has an alternator driven off the rear of driveshaft fot the Nitrous system. That would be cool because yous the alternator for the pick up

 

[Beamer]

I guess I did not explain more of why I am asking this.

What Adam mentioned is why I am asking this. I am helping a friend find a way to connect an input to a LM2 to datalog the driveshaft RPM for calculating convertor effectiveness. He is a Buick guy, but a big block person.

I have been helping him get ready to install a data logging system in his car. He was talking to a speed shop that he deals with about componants he needs to get. They said that he needs to mount the pick up to the differential, and he is running a GM 12 bolt which has very little to no room to fasten to at the input snout.

I am thinking that, as mentioned, up toward the tranny output would be best due to movement is less than by the differential. But we do not know any particular device to order. I remember the old cruise control systems also, and know there has to be some easy setup. I am hoping someone can say.... Blah, Blah, Blah... Summit has these for $??? amount. They will provide a signal like a tachometer does.

Innovate sells a serial expander that allows an additional RPM input, we just need to device to give the signal.

Thanks again for the inputs. It is very much appreciated.

Mike

 

[lazaris]

Autometer Dual Channel Playback Tach with Tachfacts software.

 

[V8Assassin]

Autometer Dual Channel Playback Tach with Tachfacts software.

Nice!

My next obvious post was going to be Call Cal!

 

[Sam Colalillo]

Mike very good data indeed to be collecting.

It is the most effective and accurate way I know of to calculate converter slip. It is also great data to have when determining wheel speed on launch. This and an accelerometer are to must haves in my opinion for analysing the launch.


I am running the the FAST drive shaft speed sensor kit. It has a split ring which bolts to the rear end yoke. (Split ring meaning it un bolts and splits into two halves. Then slip it over the yoke and bolt it back togethor). I have an after market billet yoke and had to do a little machining to make the large 2.1875 inside diamter spilt ring which came in the kit fit my yoke. Then I made an aluminum angle bracket which holds the drive shaft speed sensor in line with the split ring. (basicly the same concept as a crank tigger). I drilled and tapped a hole into my 12 bolt housing. Then mounted a 5/16 stud into that tapped hole. That stud holds the mounting bracket for the sensor. The kit comes with brackets for the sensor which mounts to the studs on the front side of a Ford 9 inch.

The part number is 301436 for the kit I got from Holly.

 

[Beamer]

Thanks Sam for the info. I will forward this to Fernando. I am sure it will be a huge help.

Mike