my uncle has a poniac GTO very fucking fast btw and he has a hand held dyno or so he says it plugs into the ciggaret lights u put in the weight of the car and do something else cant remember....then u floor it 1st threw 2nd then slam on breaks and it give u your quarter/hp/torqe/and 1/8 time

anyone ever heard of this and if so how accurate are they

It's only an estimate, I'm not sure how close they actually are. DSMLink has that too.

i thought he was full of it lol. But i would like to know how accurate thease things are. Wheres Kevin when u need him.

http://www.gtechpro.com/index.html
That it? I've heard they are fairly accurate.

yea thats it

Yeah the G-tech. I've heard they are fairly accurate, IIRC they are within 1 tenth in the 1/4. My friend had one in his Fiero. He g-tech'd it after he had all his mods done and the estimate was I think .08 seconds off of what his fastest time in the car was at the track. Not real great, but its a damn good guess.

they're only as good as the information you put in, garbage in, garbage out.