I just tried out my G-tech today. got it set up and dialed in my weight as 3795 (which it is with me and one passenger). it said go, i went and i only came up with 144 hp. that is way off. any advice?? i did the test again and got nothing better all 4 times. i tried it through all the gears and still nothing better than 144 which i achieved in 1st gear only.

i have an 89 iroc with a 305 (rebuilt to 312) with some good mods. i dynoed the car last year and got 220rwhp, but this was before i had headers, crank pulley, ram air. any help is worth my while. thanx

 

Just don't know about these g-techs. The 1/4 mile seems like it's almost dead on. But I doubt that my Iroc only has 125 hp or that my friend's honda that runs a 15.0 in the quarter only has 90 or that my brother's firebird with a 428 only has 190.

 

yeah, i was wondering if anybody else was experiencing this. my friend with a modded neon got 88 hp and a 12.65 0-60 time peeling out through all of 1st. u say the 1/4 time is pretty much on though?

 

1/4 times are off by about 2 tenths and mph is usually off about 2 to 3. This of course is if you get a good launch without any wheelspin. My car's best so far is a 14.20 @ 100 mph on the gtech spinning all through first lol. I've fixed a couple problems since then so I'm hoping for 13.90's next time Of course at the track with a lot more traction, I'd probably be low 13's maybe high 12's as the car sits now.

 

I seriously doubt it you had 220HP at the rear wheels. Just because it was done on a chassis dyno doesn't mean it's RWHP. There are ways for them to calculate what the FWHP is.

220 HP at the rear wheels = 275 HP at the flywheel at 20% drivetrain loss.

Do you really think you have that much HP?

If you've run the 1/4 mile, use the ET in this calculator...
http://www.smokemup.com/auto_math/hp_et.php

and the MPH in this one...
http://www.smokemup.com/auto_math/hp_mph.php

If those links don't work for you, you'll have to join that webpage.

 

why would u dought that my car would have 220 rwhp. it's not stock as i stated. i had it dynoed. rwhp. "dynojet" dyno. at the local speed shop. that was before some other good mods. i'm probably pushing around 250 currently. this is no lame 305...

 

i'm sorry you had 220RWHP without headers???? you know the highest rated 305 motor at the crank was around 220HP. How'd you get sooo much more?

Personally, i built up a 300HP 305 at the crank following a build up I saw from a local guy. At a 25% driveline loss I would have 225RWHP. This is what I expect to put down. You think you're going to have 250RWHP which would be a ~325HP motor.

Now unless you have heads/cam/and non-stock TPI I can not believe this to be true. I have done a LOT of work to my motor to get it to where it is today and I have my doubts here. My motor is not emmissions legal by any means and is running true dual pipes and a few other things which make it less street friendly.

Let's see some mods and dyno slips please.

 

I think if you drop the original G-Tech Pro to many times, it gets knocked out of calibration...Send in for service.
I say that because mine old G-Tech used to work, and after dropping it to many times over a couple of years, my Impala now idles through a parking lot at over a 100HP, and my Vette screaming down the road gets 68HP.

I finally gave in and bought a Pro Competition over the summer. Now this unit is very consistent, and is self calibrated with many more features. You can even upgrade it on your PC. It's F'in nice. Even has a very nice dyno software that you can dump your runs into.

Sale the old one, get the new one - worth it...

Ron

 

well, 220 rwhp is very modest. and why would u figure 25 % drivetrain loss? autos are said to have 15% and manuals 12%.

as far as the motor, i said it wasn't stock. it's a 305 bored .040 (312ci). Ramjet 350 cam headsbowl job with 3 angle valve job an milled .030 to bring compression to 10:1. 1.94 intake valve to replace the stock 1.84". base plate was ported by hand to try and match the ports. plenum was ported by me also removing what i could and the little wall thing on the front behind where the throttle body goes. stock tb. little thing like air foil, removed maf screens, tb bypass, to give about 5-8hp total. hooker catback with no cats, and alluminum driveshaft to help get rid of some driveline hp loss. tesating was done with hood open but still with air lid hooker up. those were all the mods i had as of testing time. remind you that GMHTP magazine tested their 150,00 mile 89 formula 305 (5 spd) that made 230 some hp with pulleys, slp runners,air foil, maf with removed screens, porting the plenum wall thing, made 236.9 hp % 303lb.ft. torque. this was a 215 hp 305 5 spd motor, but still on stock 150,000 mile motor. this was not on open MAF runs either.

 

my bad some started to get cut off. cam is a ramjet 350 with 1.6 rr's. lift with 1.5's is .431/.451. i have'nt taken the time to figure it out with 1.6's yet. not a high rpm cam but very torquey from 2500 on up. heads are stock but smaller bowl job and porting along with 3 angle valve job and a 1.94 intake valve.