Are GTech-style accelerometers useful, or just a gimmick?

My primary interest would be in gauging the before-and-after effectiveness of mods (hp and torque vs. rpm), without breaking the bank on dyno runs.

I did a search on this forum, and the only thing I found that even came close to a "review" was this:
http://www.bonnevilleclub.com/forum/...ighlight=gtech

Willwren has one in the ZIlla and seems to use it alot


Bill would be your best source of info

I'm on my second. The ONLY thing it'* accurate enough for is determining shift points and what RPM'* your horsepower and torque PEAK AT. Not anywhere close to accurate on hp or tq peak values, only the rpm at which they peak.

It'* all over the map (both I've owned, and another I borrowed) on hp and tq numbers, and not much better on 1/4 mile times.

Bought a Gtech Pro Comp.
Borrowed another to see if it had the same results.
Bought a Gtech Pro RR.

All 3 had the same results even after hot/cold calibration.

I've had the RR about 45 days.