G-Tech pro Fanatic RR or others??

[seangti]

Hi, I'm chasing input from people who've had experience with the g-tech pro fanatic. I'm really only interested in lap times and segments rather than the other features which accelerometers provide, which means the RR version rather than the SS version is needed.

I'll also likely be getting an iPhone shorlty and reading a little about the Dynolicious app, which from what I can tell doesn't provide lap times. Any other apps worth researching? I have an android tablet, so that could also be an alternative if an App would suffice.

Sean

[99_FGT]

I was looking around for these on the weekend, and not having much luck.
Since found these:
iOS
App Store - Harry's LapTimer Pro
Android
Trackmaster - Welcome

[VWindahouse]

Hey there, I currently have the SS model and think it's a pretty cool bit of kit. Functionality wise I mainly use it for 0-100 times now because the quarter mile function and the peak HP and torque function require a straight flat "private road" because of the speeds you will hit to complete the function (ie revving out 4th). But now I'm enjoying more circuit work for the first time I will probably go for the RR upgrade SD reader for lap times. Then the cornering G force readings will come in handy too.

The unit itself is easy to use and attach, and It never really goes below 8 satellites in connection at one time (out of a max of 12) so I guess the accuracy is pretty good.

Hope this helps!

[AdamD]

As above, I have the SS too, and have had lots of good experiences with it on several cars. Only downside is that it takes forever before it gets a decent lock on a large number of satellites. I usually need to make sure it's been running for at least 5 mins before I take off.

Not done any track work in my car myself, so didn't bother going with the RR expansion. I do suspect, however, that it'd be far more accurate than any iPhone app.

[seangti]

Thanks for the input guys. I've had a closer look at the trackmaster app, it looks pretty awesome, though they recommend running an external GPS for much improved accuracy, increasing from 1hz which your phone would do to 5 hz (so recording data at 5x per second rather than 1). If I can get the tablet (or Iphone) to pull that GPS signal from my pioneer headunit/GPS, I may be in luck, not sure if that's possible or if the headunit records at 5hz. Looking at ~$100 for an external GPS, in which case I'd spend the money on the g-tech to do it right the first time.

1hz is pretty useless and can't be particularly accurate.

[AdamD]

1hz is pretty useless and can't be particularly accurate.

Yup, absolutely. 10Hz minimum for acceleration testing, 5Hz for track work I reckon.

[seangti]

Yup, absolutely. 10Hz minimum for acceleration testing, 5Hz for track work I reckon.

Thanks Adam. I'm nearly sold on the G-tech being the best tool for the job. Value for money, etc.

A bloke I used to work has a Vbox Lite - http://www.racelogic.co.uk/_download..._Lite_DATA.pdf, phenominal piece of kit, but expensive (~$1900 I think). It's on his race car, so warrants something a bit more serious.

[AdamD]

A bloke I used to work has a Vbox Lite - http://www.racelogic.co.uk/_download..._Lite_DATA.pdf, phenominal piece of kit, but expensive (~$1900 I think). It's on his race car, so warrants something a bit more serious.

I have a feeling you can pick up a new VBox (there's a basic stripped down version for your average Joe - not sure if that's the "Lite") for around the $500-600 mark via eBay - that's what I saw when I was researching. Not sure of the features available to support track work though - I was focussing on outright performance testing only. The VBox is used by many professional motoring magazines and is generally considered to be the benchmark product, but their cheaper offerings are only 5Hz or 10Hz, like the G-tech, and still command a premium!

Edit: Here we go, the 10Hz VBox Mini: http://www.vboxaustralia.com.au/vbox%20mini.html

It is ideally suited for performance testing, lap timing and long term durability testing. However, this unit is not recommended for Brake testing.

[seangti]

The Vbox (PerformanceBox) mini looks good, though is pushing $600. Getting a little serious for my purpose.

[seangti]

Well I've order the GTech pro RR. Should have it by end of week. Have lakeside next weekend and QR end of July to test it out.

[seangti]

Thought I'd provide some details of the gtech after a track day and last night doing some timed runs.

Screen shot of the PASSv1.22 software for review laptimed data:


Unfortunately for this event I got very little clear track time so the lap times are ordinary, I'm off to QR in a week so that'll hopefully give me the opportunity to get a clearer track and therefore much improved consistency of times. I find the PASS software pretty good, though much prefer to pull the raw data into excel so I can better interrogate and compare what's going on, as per below. It's speed against distance for the fastest three laps, in a per sector sense. The Pass software uses time as the primary measurement, so I've used excel to change distance to the primary:

I had to back out of one of the laps at 2/3s the way due to traffic, which is seen clearly against the speed.


I also graphed the g-forces (lateral and forward) over one lap. You can see when and how I've transitioned from acceleration to braking and steering into/out of a corner. Hopefully at the next event I'll have some consistent clear laps so will be interesting to overlap this graph across a number of laps to see if it's also consistent. This will demonstrate if I'm reaching max cornering/braking.


Last night I did some timed standing start runs. Really the first time I've every tried drag style starts. It's was very wet so the times themselves are near irrelevant as I'd spin through 1st and 2nd gear. It's interesting to see the black run was the fastest though also produced the lowest g-forces as id spun through 1st and 2nd more than on the other 2 attempts.

G-forces


HP produced

Ignore the horsepower figure itself as that's not accurate for this activity, but you can see the where I've had grip, or not.

There's another feature in the gtech for horsepower/torque, though at the moment I haven't got consistent enough results to be comfortable, nor was it the purpose of buying such a "toy".

This is the speed during each run and rate of acceleration



These runs were done on a highway without breaking the speed limit

[seangti]

Another great day out at Queensland race on the national circuit.

Some data from the day




Lap times



Max Speed 173.83
Lateral G's: 0.55 to -.52
Longitudinal G's: 0.39 to -.96

Last time out on the Clubman circuit with very cold air temps my acceleration speeds was quite a bit higher down the back straight and start finish line. I'd say that shows the difference in air temp between the 2 days and the heat soak I was experiencing with the factory side mount intercooler. When on the clubman circuit, air temp mid single digits, y'day at QR was high 20's. My corning g's are near identical. There is a consistent trend that with a slow/cool down lap prior, I was carrying 2-3km/h more over the start/finish line.

Clubman Details
max speed: 178.27
Lateral G's: 0.57 to -.48
Longitudinal G's: 0.37 to -.93





When time permits next, I want to do some in gear power runs in 2nd, 3rd and into 4th to best gauge ideal shift points. I usually shift around 6000rpm - 6200rpm, rarely ever going above that and using 3rd and 4th gear only at QR and lakeside. Neither circuit require 2nd gear and will still spin through third gear with a little steering lock.

[seangti]

Perhaps a bit of a pointless update, but given there is very little practical information on here about laptimers, I'll add to it anyway.

Of late I've got into recording the trackdays, as well as GPS logging. I tried an itunes app called CMSLaptimer. It's an iphone app, capable of using an external GPS, or your internal, and records via your phone, just like Harry's Laptimer and many others, but much cheaper - data logger is currently free, the pro version with video was $3 or something when I got it. I've had mixed results with it, the first (and 3rd) time I tried it, it didn't record anything though I'll accept a level of user error. I spoke to the developer of CMS who was very helpful and quick to respond. Second time it worked fine. Though that track day had lots of traffic so getting consistent laps was difficult and it's not clear how I can change the sectors/beacons so I can have the start finish line where it should be. Though on a few consist laps it was within a couple of tenths of a second of the gtech unit - which is pretty good given the start/finish lines were about 400metres apart and using internal 1hz gps.

Anyway, regarding video, I've used a go pro hero2 and also my phone camera to record, by using RaceRender (free version gives 3minute overlays which I put into windows moviemaker for longer videos) I've been able to overlay the raw data (csv file) from gtech into the software with video. Racerender is quite easy to use after a few minutes playing around and has lots of different "dash boards" available. Below are a couple of videos from differing days. All the data is direct from gtech. This weekend I'm going to us a compact camera (Sony NEX5) with a window suction mount for video and gtech for logging. Apparently the NEX-5 share the same video sensor as the Sony Action Cam.

Whilst any dedicated GPS logger can be considered expensive, I've found the gtech to be very easy to use and reliable. I have looked into external GPS units and OBD logging by using the phone which would come to much the same price overall. I've also considered addding OBD logging to CMS as something a little extra so you get throttle position, revs and selected gear. That's a lot of logging for little money. I chose not to go down the iphone + external GPS path as I wanted to know it'd work every time with little fuss, the gtech has delivered that.