Got my G-Tech!
May 20, 2004, 02:54 PM
#31
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3500 lbs? Are you saying the Evos are as heavy as a base model 3K GT SL? It's very hard to believe. In fact more heavy than a C4 or C5 vette weight who floats up to 3400 lbs?
May 20, 2004, 09:40 PM
#32
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Originally Posted by erioshi
Sorry if I wasn't clear on getting the HP & Torque map. You give the car a firm start in 1st (just a quck bump to trigger the G-Tech, no more than 5-10 mph), then put it in 3rd or 4th and floor it. Hold the car floored until red line. When you download the data from that run it produces a nice even "dyno" plot.
May 20, 2004, 09:51 PM
#33
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well, according to the g-tech instructions, you should do all horsepower runs in 2nd gear. they say you will experience the least amount of drag. it makes sense, since it factors in EVERYTHING like wind, road condition, among other things and the faster youre going, the more wind drag youre going to create. you have to realize that it is NET horsepower as well, which is the LOWEST form of horsepower.
May 21, 2004, 02:23 AM
#34
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Good to know about the 2nd gear thing; I've been doing all of mine in 3rd. I'll have to go re-test in 2nd now. I just finished gathering some new data for my planned cam install this weekend.
I think you can also start a run with a button, but if your RPMs drop below 1K the run is discarded. I know you can collect data from a rolling start, but I haven't tested that yet. I will be trying that with different cam gear settings once my new cams are installed and broke in.
For me, the 3500 lb weight figures an Evo with a beefy 190lb driver, spare tire and full tank of gas.
I think you can also start a run with a button, but if your RPMs drop below 1K the run is discarded. I know you can collect data from a rolling start, but I haven't tested that yet. I will be trying that with different cam gear settings once my new cams are installed and broke in.
For me, the 3500 lb weight figures an Evo with a beefy 190lb driver, spare tire and full tank of gas.
Last edited by erioshi; May 21, 2004 at 02:32 AM.
May 21, 2004, 10:07 PM
#35
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Hmmm... did the 2nd gear thing today. Got the HP reading but my torque reading was all messed up. 454ft lbs torque? What am I doing wrong? Is there something simple I'm missing?
May 22, 2004, 12:29 AM
#36
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The high torque reading is one reason to use 3rd gear; I had a plot of 873 lbs of torque in 2nd, yesterday. 
The other reason is wheelspin - I bumped into some mild wheelspin problems in 2nd when the boost really hit. Just a bit of slip with the right front wheel, but I'm sure if I could feel it, so could the G-Tech.
I think the reason the torque readings are so high in 2nd is that you are using the gearing of the transmission to multiply your torque. On a static dyno, plots are generally run at as close to 1:1 as possible; in an Evo that usually means 4th gear. I haven't had the chance to try plotting in 4th gear with my G-Tech, but I suspect that drag would really hurt the numbers.
The other reason is wheelspin - I bumped into some mild wheelspin problems in 2nd when the boost really hit. Just a bit of slip with the right front wheel, but I'm sure if I could feel it, so could the G-Tech.I think the reason the torque readings are so high in 2nd is that you are using the gearing of the transmission to multiply your torque. On a static dyno, plots are generally run at as close to 1:1 as possible; in an Evo that usually means 4th gear. I haven't had the chance to try plotting in 4th gear with my G-Tech, but I suspect that drag would really hurt the numbers.
Last edited by erioshi; May 22, 2004 at 12:36 AM.
May 23, 2004, 03:05 AM
#37
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I would guess that there's something going on besides that. The one hard launch I did going 0-60 I got much more reasonable torque readings. There's no way that the 454 ft/lbs of torque that I got on the 2nd gear run is correct. Must be something wrong with what we're doing...
May 23, 2004, 03:38 AM
#39
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There is another option, the Beltronics Vector. With it my stock Evo showed 277 HP and 269 LBS-FT of torque, using a driveline loss of 18%. It is about the same price as the G-Tech, which I also have.
Sorry about being slightly off topic.
Sorry about being slightly off topic.
May 23, 2004, 09:46 AM
#40
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ok, erioshi - did another run today... 2nd gear but ran it in 3rd a little longer.. got 250hp and 260ft lbs torque which seems reasonable considering my mods... no wacked out torque numbers...
May 23, 2004, 05:28 PM
#41
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Helps to read the instructions
Ok Eroshi - got it figured out. finally broke down and read the instructions. what a concept.
when viewing the HP vs TQ vs RPM graph, you can use the directional pad to review the data from each point along the TQ vs RPM graph.
Using this method, during 2nd gear runs, my HP has ranged from 242-245.3 and my TQ has ranged from 241-248.3 lb/ft. Data seems pretty consistent and believable (numbers seem reasonable with my mods)
I'd be interested to see other people's numbers in 2nd gear "pulls", for comparison.
when viewing the HP vs TQ vs RPM graph, you can use the directional pad to review the data from each point along the TQ vs RPM graph.
Using this method, during 2nd gear runs, my HP has ranged from 242-245.3 and my TQ has ranged from 241-248.3 lb/ft. Data seems pretty consistent and believable (numbers seem reasonable with my mods)
I'd be interested to see other people's numbers in 2nd gear "pulls", for comparison.