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Hey all just wanted to ask the forum members a quick question. I have a g-tech pro the rr version so you kno I had to take my car for a spin to see how the device works. I have everything setup and i went for a straight line run, I must say it disturbed the hell out of me I have a 95 gtst with the following mods 3" turbo back exhaust, pod filter, fmic, stage three clutch, boost turned up to 10 psi, plugs gapped to .8mm, no tune and running 91 octane gas as that is the only gas available over here and it is probably 95 ron to you guys cause we import directly from the U.S.A.. Nehow heres the prob I took my car on a quater mile run and came up with some disturbing numbers FOR HORSEPOWER i got a figure of 183 and a quatermile time of 15 seconds on average. Now the time isn't Really an issue but the hp figure, 183 comeon I have to have more horses than that and I have the weight of my vehicle as 3500 pounds. With the mods I have listed does this power figure seem correct. Also wanted to know if I could use xylene in place of toluene as an octane booster and if there are any negative effects to the cars engine as compared to using toluene? Thanks in advance guys.

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your ECU has probably dropped back onto the lower octane maps, which is cauing you to lose power. depending on how realistic the dyno is, you probably shoudlnt expect much more than 200 or so hp with those mods anyway... i'd say once you get some 98ron fuel and reset the ECU, you might get 200 - 220 hp.

For benchmarking purposes, I got ~230rwhp with 3" turbo back xorst, high flow cat, FMIC, 12psi, pod filter, cold air intake and SAFC2 tuned by matt spry @ PITS.

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weird, do you have the exact weight of the car?

I've got a G-Tech pro RR at home, that's the one with the serial cable to download the data?

basically what i do is,

plug it in:

put in car weight first

then calibrate the RPM

then do the axis calibration(what a pain in the arse to do)

then put in a shift light, i have it starting at 7000(so two lights hit on), then 7500 the four lights go on and I change gear

183hp sounds really shifty though :S I got 194 on my GTS4 auto!!! and a 14.6 1/4, so there must be something odd going on :D

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oh and I'm using 98RON so you might want to see if you can get some better petrol, then once that happens, reset the ECU(remove positive from battery, then put foot on the brake for a few seconds), then try it :D hopefully it gets better, post up your new scores :)

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weird, do you have the exact weight of the car?

I've got a G-Tech pro RR at home, that's the one with the serial cable to download the data?

basically what i do is,

plug it in:

put in car weight first

then calibrate the RPM

then do the axis calibration(what a pain in the arse to do)

then put in a shift light, i have it starting at 7000(so two lights hit on), then 7500 the four lights go on and I change gear

183hp sounds really shifty though :S I got 194 on my GTS4 auto!!! and a 14.6 1/4, so there must be something odd going on :D

Dont Have the exact weight just put in 3500 pounds as a rounded off figure. The axis calibration is when you take off to get the g-tech started but only roll forward a couple a feet so that the directional arrows work, did that if thats what u meant.

oh and I'm using 98RON so you might want to see if you can get some better petrol, then once that happens, reset the ECU(remove positive from battery, then put foot on the brake for a few seconds), then try it :) hopefully it gets better, post up your new scores :D

Yea my gas is real shitty over here only gas available is your 95 ron equivalent. So I'm gonna start mixing my own brew getting the ron as close to 98 as I can then I will reset ecu once I have ran a complete tank thro my system and start using my mix everytime I fill up and see what happens. Will post my results. I really think its the gas, plus I have no tune the tune is stock.

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The Gtech uses the weight as an input to the calculation of horsepower, so that needs to be accurate and include everything - so dont forget to add the weight of the driver (and passengers). Also it will read a bit low on horsepower as it assumes no wind resistance.

The quarter mile time on the other hand is directly calculated from the accelerometer input, and should be very accurate.

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