Your still young Keith, keep asking I do. 
Gone High Tech!
- Thread starter Ishiftem
- Start date
You get the input RPM with a magnet in the input shaft and a pickup in the collar. I think
A little bit of extra knowledge banging around in your head (even if you can't use it) may help someone else. That is why facts based on specific Empirical evidence created by someone and shared with the rest of us gives us all the correct information so we don't mess up what we work so hard for. I tried to tune my Wagon at Tri-State drag way "by the book". I only had a few minutes before the car had to run down the 1/4 mile and my tune was off. Nate and my Dad stepped in and tuned the car by ear and she ran great. I have yet to change what they did because once I got home I found that my knowledge had slipped and I was doing it wrong. Anyway, soak it up! 
I know Petey. Keep asking. I like explaining and helping people make there cars faster.
Usually it is not a problem as it can't make any adjustments to the car, only give info after the fact. Some of the programmable ignition boxes like an MSD Grid are not allowed though as they can be rigged to make adjustments on the fly by adjusting the slew rate so if the air gets better, the timing will adjust or rev limiter will kick in to keep the et the same.I assume you are not allowed to use this in competition.
The most popular way is to drill the input and install a magnet and weld a bung into the bearing retainer for the sensor. I don't have room for that in my bell housing. Others have put a collar with a magnet on the counter shaft or something like that. I have a Cummins proximity sensor that counts the teeth on fourth gear. That requires a little box for the data logger that converts that signal to something the logger can use. The software then does some math to give the correct reading. I just had the case spot faced and tapped for the sender.
Qualifies as high tech by my standards. As I’ve always said, you can go as fast as your wallet will take you. Knowing what to do with all this information you can now get and then doing it on a 1/4 mile track is very impressive.
Great thread!