I was in another users car last year, a WRX and he had a shift light that used LEDS and had 3 or 4 of them. 2 green, a yellow, and a red one. Red was the last shift point, yellow was 100 rpm,and the other 2 greens were 100 rpms each before.

Is something like this possible to work out for a fox mustang?

 

I'm sure it is. Its still going to read from the negative side of the coil. The shift light would just have to do the calculations and light the correct light. The only problem I could see is that since a Mustang is actually fast , you won't have much time between the "warning" light and the actual shift light (at least in my car anyways)

 

for drag racing yes. But I want something to let me know where im at int he RPM range and when to shift,for auto-xing/road racing. Rpms dont climb that fast in 2nd gear.

 

Not unless you have a fast car

 

last I checked dave you were only a tenth or two faster than me at the strip

 

Yeah, I know. But my car sure as hell doesn't spend much time in 2nd gear. Remember, with the torque my car makes, it spins the tires pretty hard.

I was going to refer you to Harlan (he made my LED shift light) but his web site says his store is closed