accuracy of Gtech Pro device

[louis]

hello,

all these threads on ecu tuning and mods to gain additional HP has got me thinking of a more economical way to measure HP increase.

each dyno session is like what, $80? gtech pro is selling for USD199 for the basic kit off the web, which is roughly roughly 320SGD? that's like the cost of 4 dyno runs right? advance RR kit's got software and all that jazz for extra 100USD(or the cost of 2 more dyno runs)

ideally for each mod, you do one dyno before and one dyno after, so you'll break even after only 2-3 mods.

plus for those who want to go for ECU upgrades, you can now have BOTH a road and pseudo-dyno tune at the same time and for programmable piggybacks, good way to find out if your ecu has over-ridden your piggyback's input while in the closed loop right?

besides, it has been cited that the dyno is limited in that the car is stationary, so you can't accurately measure the ram-air effect of intakes, cooling of intercoolers blah blah blah. gtech should be able to oversome these since HP can be measured while car is actually moving...

good idea?

by the way, if you're clueless as to what the hell i'm talking about, see:
http://www.gtechpro.com/index.html

so this obviously begs the question:

1) how does gtech pro actually measure HP/torque?
2) how accurate and sensitive is it? are the manufacturer's figures of +/- 1% to be believed?
3) is it transferable from car to car?
4) does it work on BMWs?
5) anyone has one for sale? hehe

please feed my thirst for knowledge........anesthesiology is like freaking putting me to sleep...

 

[chickenbackside]

Re: accuracy of Gtech Pro device

This looks very very interesting...

 

[louis]

Re: accuracy of Gtech Pro device

ok, some googling has revealed that it is indeed transferable. maybe the workshops should buy one to back up their claims of HP gain for some mods.

butt feel no more.........

chickenbackside, how? GB? or maybe one whole group buy one and share...hur hur

 

[eddie]

Re: accuracy of Gtech Pro device

good stuff....

i have one.....

 

[louis]

Re: accuracy of Gtech Pro device

erm.... thanks for you detailed review bro. i mean, i know a picture's worth a thousand words, but.......

 

[eddie]

Re: accuracy of Gtech Pro device

yes, it works on the BMW and it is transferable from car to car.....

pretty accurate stuff me thinks

U can test the quartermile, the century sprint, the HP / Torque, nice gadget

worth while getting one

if only i lived in SPORE, u can try mine anytime...

 

[chickenbackside]

Re: accuracy of Gtech Pro device

ok, some googling has revealed that it is indeed transferable. maybe the workshops should buy one to back up their claims of HP gain for some mods.

butt feel no more.........

chickenbackside, how? GB? or maybe one whole group buy one and share...hur hur

This is something that I really don't mind getting. At USD199, I think it may be ok to get our own units.

Damn it, if I only knew about this sooner...

 

[hetraa]

Re: accuracy of Gtech Pro device

been wanting to buy it ages ago..
i tried to find at mcwell, but they dont carry.

basically for accuracy u need to buy the G sensor, and need the exact weight of your car to key in.
without this two, still can calculate , but there will be very slight +/- to yr readings

and its slotted to cigarette lighter , means transferrable and very worthwhile buy...good to substantiate HP gains with this device

 

[VenomX2]

Re: accuracy of Gtech Pro device

sounds interesting but don't you need a track or some clear road to do the actual tests.

 

[SMYUEN]

Re: accuracy of Gtech Pro device

Louis - yeah... heard its a good product...
anaesthesiology? if it puts your patients to sleep, it can also put you to sleep.

i nearly died when i did my posting... SO BORING!!!!!! awww man.......

or could you be smelling too much gas?

 

[Shaun]

Re: accuracy of Gtech Pro device

Even the first generation Gtech devices were good enough testing tools. Newer ones should be even more repeatable with full 3 axis accelerometers and ability to "self-level" and compensate for squat.

What is more important is the test process and process control. I'm not sure if Ting Yong still is around (nickname "NTY" on here) but he used to test a huge array of cars and keep a database on them I believe. He also was meticulous in testing - trying hard to make runs in similar weather across the same flat stretches (he'll tell you where), averaging rapid succession runs in both directions to eliminate wind variable, etc.

If you can contact him he'll probably tell you more. If a thread on testing eventually gets started I will be happy to participate in it.


My own suggestions for now are to

1) keep the runs individual and not paired because competitiveness is just another variable and trying to outdo other cars just makes you slip and wear clutches, tires, and not keep things consistent which is exactly what needs to be done when trying to evaluate changes and not race for wins.

2) forget about finding out HP since it is dependent on how good the RPM calibration and sensing is (varies) and other user inputs (weight, Cd, frontal area). Also, most autoboxes add large variable to it which cannot be compensated for. Focus on relaxed and consistent launch, and plain ElapsedTime@speed. Above all else, quantify gains in trap speed increase.

3) keep records of all runs. Things like time of day, rough temp and humidity, wind, tire type and condition, ECU fuel trim and error codes if any , how many km at last ECU reset.


Suggest reading through all the Gtech site FAQs since many answers on device inner workings can be found there.

 

[pingman]

Re: accuracy of Gtech Pro device

if the folks doing the ecu tuning can provide this device as value added service for pre/post tuning result. it will be nice...

 

[MaxPower]

Re: accuracy of Gtech Pro device

each dyno session is like what, $80? gtech pro is selling for USD199 for the basic kit off the web, which is roughly roughly 320SGD?



good idea?

i'm pretty pi**ed off with those kiddies @ gtech ... here's why ...

i had a bunch of questions that i wanted answered BEFORE i spent my hard earned money on their gizmo. altho their support page says that queries will be answered in 2-3 days, FOUR reminders over the last SIX months has elicited ZERO response from those idiots.

their product may be good, but i believe there may be inherrent flaws in the design that will prevent accurate readings - and too many "if's & buts" for any degree of accuracy.

i, for one, do NOT want 2 get a toy that will not do what it is supposed to. by not responding to my queries, they are effectively hiding the truth regarding their product.

they ignored a potential customer before a sale. i have NO reason to believe that i will have after sales support.

they have their plate full with local orders. they do not give a s**t for international orders.

 

[Shaun]

Re: accuracy of Gtech Pro device

i'm pretty pi**ed off with those kiddies @ gtech ... here's why ...

i had a bunch of questions that i wanted answered BEFORE i spent my hard earned money on their gizmo. altho their support page says that queries will be answered in 2-3 days, FOUR reminders over the last SIX months has elicited ZERO response from those idiots.

their product may be good, but i believe there may be inherrent flaws in the design that will prevent accurate readings - and too many "if's & buts" for any degree of accuracy.

i, for one, do NOT want 2 get a toy that will not do what it is supposed to. by not responding to my queries, they are effectively hiding the truth regarding their product.

they ignored a potential customer before a sale. i have NO reason to believe that i will have after sales support.

they have their plate full with local orders. they do not give a s**t for international orders.

I think we should separate poor customer service from product quality and not let emotions mix the two - especially not over a couple hundred dollars that are still in your pocket.

"too many "if's & buts" for any degree of accuracy" is sweeping especially when many have found it to be accurate. The first generation of Gtech was repeatable and reasonably accurate when the user did things right. This new generation only makes things easier.

It would be interesting to hear from you what these supposed "inherent flaws" are. That way potential buyers can make an informed decision.

 

[m3magic]

Re: accuracy of Gtech Pro device

Hi MP,
I can understand your frustration. Poor customer service is always frustrating. I can say the same for Rob of DMS for that matter as well.

However, I agree with Shaun, the Gtech toy is quite fun and accurate. We used to have one 1st-gen and one 2nd-gen Gtech among our forumers here that we were passing around (not sure where those toys are now ... hehehe ), among probably 10-15 of us, did multiple runs, got quite consistent results.

I guess you have to take it as "a couple hundred dollars TOY", and not expect it to be like "thousand dollars precision equipment", and you will be fine.

How's that bloody M5 of your? run-in already?

ns

i'm pretty pi**ed off with those kiddies @ gtech ... here's why ...

i had a bunch of questions that i wanted answered BEFORE i spent my hard earned money on their gizmo. altho their support page says that queries will be answered in 2-3 days, FOUR reminders over the last SIX months has elicited ZERO response from those idiots.

their product may be good, but i believe there may be inherrent flaws in the design that will prevent accurate readings - and too many "if's & buts" for any degree of accuracy.

i, for one, do NOT want 2 get a toy that will not do what it is supposed to. by not responding to my queries, they are effectively hiding the truth regarding their product.

they ignored a potential customer before a sale. i have NO reason to believe that i will have after sales support.

they have their plate full with local orders. they do not give a s**t for international orders.

 

[MaxPower]

Re: accuracy of Gtech Pro device

I think we should separate poor customer service from product quality and not let emotions mix the two - especially not over a couple hundred dollars that are still in your pocket.

"too many "if's & buts" for any degree of accuracy" is sweeping especially when many have found it to be accurate. The first generation of Gtech was repeatable and reasonably accurate when the user did things right. This new generation only makes things easier.

It would be interesting to hear from you what these supposed "inherent flaws" are. That way potential buyers can make an informed decision.

u r correct. i did mix the 2. it is suposed to be an excellent device, but the frustration of getting answers prior 2 purchase from those ppl made it an exasperating experience.

here are some of the questions i asked, for which i have received no responses ...

--- I drive a Porsche 996TT tiptronic. It's difficult to get & hold 4,000 RPM without load to the engine. How will RPM calibration then take place?

--- I have a sport exhaust. Will the extra resonance from it disturb any of the calculations the Gtech makes?

--- Due to modifications, I experience wheel spin and tail wag even at speeds over 120kmph, with PSM engaged, if I hammer the throttle. Will the HP/TQ readings be reliable?

what would u think if u got no answers to these questions? if i can't calibrate the unit, how can the result be accurate?

thus my comments.

 

[MaxPower]

Re: accuracy of Gtech Pro device

Hi MP,
I can understand your frustration. Poor customer service is always frustrating. I can say the same for Rob of DMS for that matter as well.

However, I agree with Shaun, the Gtech toy is quite fun and accurate. We used to have one 1st-gen and one 2nd-gen Gtech among our forumers here that we were passing around (not sure where those toys are now ... hehehe ), among probably 10-15 of us, did multiple runs, got quite consistent results.

I guess you have to take it as "a couple hundred dollars TOY", and not expect it to be like "thousand dollars precision equipment", and you will be fine.

How's that bloody M5 of your? run-in already?

well, zero response to pre-sale enquiries is worse than poor customer service simply becos it implies arrogance on their part ... a "take it or leave it" attitude. and sorry, but i have no personal experience with rob of dms. altho i hear a lot of good and poor comments about him.

also, i've just posted a response to shaun, which i hope explains my views on it more clearly .

m5 --- just got back from overseas ... now need to make a couple of "breakfast" runs to kl ...

 

[Shaun]

Re: accuracy of Gtech Pro device

--- I drive a Porsche 996TT tiptronic. It's difficult to get & hold 4,000 RPM without load to the engine. How will RPM calibration then take place?

Try harder, and if that really doesn't work, then forget about the HP reading as I suggested two posts ago. In any case, you have bigger problems like not knowing exactly how much the torque converter slips and where it locks if it does, frontal area figures (tough to get from the manufacturer, even tougher to measure yourself), drag coefficient (which changes with your mods and ride height), gear holding ability (autoboxes interfere and select lower gears automatically). Without any of these you can't find power accurately. You can still find accurate elapsed time and trap speed though.

--- I have a sport exhaust. Will the extra resonance from it disturb any of the calculations the Gtech makes?

Unlikely because that kind of vibration is low frequency and amplitude. Also, performance accelerometers and software are designed to deal with and/or filter some degree of vibration out and get a cleaner reading. The designers would have anticipated the type of environment in which operation would take place. There will also be cars on the fringe that can rattle anything apart, but a Singaporean street driven car is certainly not on the fringe.

--- Due to modifications, I experience wheel spin and tail wag even at speeds over 120kmph, with PSM engaged, if I hammer the throttle. Will the HP/TQ readings be reliable?

HP measurement requires you to run a single gear sweep at WOT, in a high enough gear that does not allow wheelslip. As mentioned earlier, tiptronic won't allow you to do this. So you're not going to be able to measure power... just forget about that and quantify mods in terms of trap speed gained, shift points equal.

what would u think if u got no answers to these questions?

The thing is... many of the answers are found in the FAQs. If a company is busy and has already taken the time to set up detailed FAQs, they're not going to reply to questions that have already been answered on their site.

if i can't calibrate the unit, how can the result be accurate?

Elapsed time and trap speed at the eighth or quarter mile marks will still be accurate.

 

[MaxPower]

Re: accuracy of Gtech Pro device

Elapsed time and trap speed at the eighth or quarter mile marks will still be accurate.

whoa ... looks like u really know this unit inside out bro ... & tnx for the advice.

and i did look at their faq page & didn't find answers to my questions ... thus i wrote to them.

cheers

 

[MaxPower]

Re: accuracy of Gtech Pro device

Try harder, and if that really doesn't work, then forget about the HP reading as I suggested two posts ago. In any case, you have bigger problems like not knowing exactly how much the torque converter slips and where it locks if it does, frontal area figures (tough to get from the manufacturer, even tougher to measure yourself), drag coefficient (which changes with your mods and ride height), gear holding ability (autoboxes interfere and select lower gears automatically). Without any of these you can't find power accurately. You can still find accurate elapsed time and trap speed though.

Elapsed time and trap speed at the eighth or quarter mile marks will still be accurate.

oh btw shaun,

then its much cheaper to buy a stopwatch ... ??? eh??? since that is apparently all it can do what with the numerous "problems" u mention ...

& i still stand by my earlier comments.