BSK181

please

43 degrees, same spot as i always test on long island's meadowbrook pkwy south to jones beach, also in and around back roads of the beach

0-60 5,92
1/4 14.45 at 102.4

second run to see i was not dreaming
0-60 6.06
1/4 14.58 at 101.7

only mod is k/n drop in

ss mode, vsa off, shifting 2/3 at 6900 rpms

Pull_T

Well, for comparison, what were your old times.

Obviously, the Gtech is reading too favorable for your car (no flame), so we/I need some kind of benchmark.

dajuice27

How far off is the G-Tech?

I read through the manual and it says that the times differ +/- 2 mph and+/- .1 seconds up to the quarter mile. I just want to know since If the G-Tech is that reliable or similar to an actual testing facility, then why flame the machine?

I just want to know since I just obtained one and I want to gauge where I am by using it periodically.

Pull_T

Well...his GTech is off about 3-4 tenths and is reading 7-8 mph high in the trap.

GTech's are consistent (If mounted the same way and used on same road), but not accurate.

pgatour1

Yeah I noticed that some Gtechs are more accurate than others. Basically. I have matched up 0-60 runs with Gtech from Stopwatch and Gtech and Gtech was always .2 quicker. Not sure what factors can cause that. As for 1/4 mile time it has alwyas been right near what I have run at the track the only difference is the trap speed on gtech is always 2-4 mph higher

dustbuster4

These posts are helpful!

I have several people swear that the GTech was not accurate, but when I would ask them how they knew, no one could answer me.

I'm very willing to accept that the GTech is not "right on", but I've always wondered how much it's off.

I mention this because even at the track, it's rare that someone will run the exact ETA, MPH during subsequent runs.

I figured the same for the GTech. I consistently get similar ETAs and MHP readings from my GTech, but was unsure how much these reading were off (as a whole).

I'm willing to wait for the tracks around here to open this spring, and run the GTech while running a true timed trail. I don't put much credence in what the trade mags publish.

BSK181

SORRY, BEEN AWAY FOR THE DAY

previous was 6.2 and 14.8 same place and similar conditions, 43 degrees

i have done about 30 runs and feel i am fairly proficient in the use of my g tech

i guess i will NEVER find out real times at the track, at the risk of
divorce (enjoy while you are young)

but, i have been driving for 33 years and have good seat of the pants feel for cars.

in the few street drags, lite to lite, i have taken 98 m3, 2000 clk 430, so, i do feel i have a pretty quick stock cl-s

Pull_T

Because the car's performance varies, not the measuring tool.

Blazin TL

i'm not trying to start $hit, just wonder if the Gtech was correct especially on the Mph reading, Pull T ran a 105 for 13s & and the gtech registered 102 @ mid 14s, shouldn't 102 be faster, unless he is spraying, but also get a bad start, this is my observation as Gtech being off sometimes...

i read a TL owner used his gtech to get better launches, if i can remember correctly, he stated that his best starts we slow pressing the accel. then flooring it...

dajuice27

Thanks for all the feedback, but like dustbuster4 said, I'll wait and test against the timer at the local track. In the meantime, I will test on the same stretch of road and continue to accumulate times for the database to use as an average against what the clock says at the tracks this spring.

I am running mid 15's, but my goal is to drop it into the 14's without spray - which is very doable.

Ming 2.7T

Gtech times in the 1/4 miles are fairly accurate. It works best on automatics. The manuals cause the Gtech to record some strange times due to the shifting .
We ran the Gtech on about 7 runs at Carlsbad Dragstrip in an automatic. 6 of the 7 1/4 mile times were within .05 with the mph of the gtech consistently 2 mph faster than the trap speed on the timeslip. THe one race that it was not within .05, I screwed up. I was fiddling with it while staged and couldnt get it zero'd. When I saw the 0-60mph time flash, I knew it was off about a tenth, and sure enough it was a tenth off at the 1/4 too!.
If you take the time and get it set up correctly it can be a good tool to measure a mods performance oncrease or decrease.
I like the AP-22 meter a little better since it shows the 10mph splits, distance and such and it downloadable to a PC. I really like that it records the distance you covered the 60mph in. Sometimes the car that is quicker to 60-mph is not always ahead of the other car.

Pull_T

Well...the next time I see a stock CLS trap 102.4 at the track, I'll come back to this thread and retact my statements about the GTech being inaccurate.

Johann

How consistent is the G-tech if you use it for comparision between different cars?
Or does it take a long time to set it up for a particular car.
I use the AP22 but it seems very sensitive to tilt and resistance factors.

Ming 2.7T

its all in the set-up. Has to be pointed straight ahead and level. If off just the slightest, it will have a skewed reading. And , you are right pull-t, there is no way a stock cls can run a 102mph in the 1/4.

They should make 2 runs, one in each direction and average the times when trying it on the street. Since not too many streets are really level.

Blazin TL

that's what i'm sayin, is no one listenin to me, i see, TL people don't get respect here...

EricL

I would expect the GTECHs to be more accurate unit-to-unit.

They will get totally different results depending on:


How much the car pitches (at the start -- will affect 0..60, HP, and ET) (at the end of the 1/4 mile due to aerodynamic forces = lift causing the speed at the end of the 1/4 mile to be WAY high).

If the car has zero lift and a "perfect" anti-lift/anti-dive suspension system (let me know if someone has electronic suspension), the unit will only be off due to yaw.

Note1: The unit is great for use as a tool. IMO, it is best used to check on the effect of mods. It is also best to use the same very flat road (for every test); if you move around to different streets for tests, you will get a bit of variation. Finally, two-way runs are a must!

Note2: They [Tesla] are coming out with a new “top end” unit with multiple accelerometers and other "goodies" that will eliminate the "screwy" readings that come from "gravity" being added to the acceleration (from squat/pitch/aero-lift). Yaw will also be corrected. There are supposed to be features to auto-detect gear changes, download options, etc, etc...


Finally: If the car has a lot of front lift -- the unit can read very high at the end of the 1/4 mile (4-8 MPH higher than computed average trap speed). If the car has a lot of "squat", the ET and 0..60 can be way too low...

BSK181

sorry dudes, been absent for a few weeks,
to clear the air, i know these times are optimistic.
the point is that i am absolutely consistent in the use of my g-tech
always installed in the same spot, alway leveled to a 00 reading and always in the same place, running 2 directions to compensate for wind,etc.
i feel that i just am improving my techniqu more and more.
and as i have said in the past, i have had a fewgood experiences on the street
last week i went out with my buddy in his 2001 mustang 5 speed vert we g-teched it a a best of 6.43, with a few 6.8's in between with both of us in the car.
we got in my car together and got a 6.83 on 1 run(got pulled over by my friends in blue), same roads
draw your own conclusions
i stil think my car is quick

RUF87

Ming - I love that point! Now is that faster or quicker?

It's one of the reasons why, say a 300ci that posted better 0-60 times than a S-type, but can still be beaten. Just one of the many variables that some folks don't know or understand.

Better watch it though . . . my good buddy 1sicklex may be watching and claim foul.

Sorry, Lex, I couldn't resist.

RUF

1SICKLEX

Those are some real impressive times not crying foul.....

AC_RENAMED

Just add 1/2 second to your times and you got yourself approx. track times.

I ran 13.7 to 1/4 mile and 5.4 to 60 GTECH in my auto 540 with no mods except Stage1 and Tranny software from Dinan...we all know my car ain't that fast.

RUF87

I thought the GTECH device WAS worth a 1/2 sec. "rolleyes:

So with H/I/RES on top of that you should knock a full sec or more off your time. . . . :P

RUF

AC_RENAMED

I'm gonna run GTECH again, now that my 19's are off and see if 17's make a difference...

I'm working a big deal at work and looks very promising, if so, bye bye 540 and hello "LOVER" ie M5

I'll run GTECH then and post 10 second 1/4

RUF87

Serious!!!

Man, I'd love to have a new one. I just checked out the latest on a series of MB vs BMW performance models and the M5 'ROCKS', as my son would say.

RUF

RUF87

Sorry, forgot to mention it was in the new Motor Trend.

RUF

AC_RENAMED

I know what you mean...I was gonna sell my 19 inch Hamanns to take my car back to stock but now with this in the picture I think I'm gonna hold onto the Hamanns a bit longer til I know for sure what's panning out.

Yeah, me and my "LOVER" hook up...I will ownz all joos!