AUTO_X_AL

Does anyone use this with the PASS software to analyze road course or autocross runs? It all sounds well and good in theory but is it too cumbersome, do certain clubs have rules against them in competition,is it too much to setup to be useful at the track, and is it user firendly and accurate. I realize this isn't going to turn me into a F1 pilot but hey every little bit helps. I appreciate all the feedback and thank you in all advance.

Al

Sidney004

I use it for road courses. The only thing I use it for is for a tally of the G forces after each session. I have never figured out how to use the PASS software, nor have I ever spoken to anyone who has. If you get a handle on how to use it, lets talk.
Sidney

John Shiels

I have one for a few years but never installed it I wanted to just see G's also.

wtknght1

It works...and worked well. I used mine to basically figure out if it was better to shift to 4th on the front straight and thru thunder valley. The PASS software will show you graphically your Gforces, rpms, etc, etc, etc. Play with it for a while and you'll see what I mean.

I am now looking for a more detailed GPS data acq system to get even more useful data.

AUTO_X_AL

I appreciate the info guys. I was looking at it from a standpoint of having two drivers we could get twice as much data and both try to optimize our performance. Example:We both run very close times almost 100% of the time and if we can figure out where we can pick up the throttle quicker or if one is braking sooner but exiting a corner with greater speed this would make both of us more competitive overall. at least on would think so. I did get a nice laptop and that was the only thing stopping me prior to this. And of course the G-force would show who was running a more effective line. Thanks again guys all the info is very helpful. And as Chris used it to figure out if its better to hold a gear or upshift. That would be extremely helpful as that sometimes can take quite a bit of useful practice time or even event runs to be sure.

Slalom4me

Some systems are discussed in these threads

http://forums.corvetteforum.com/show....php?t=1252591

http://forums.corvetteforum.com/show....php?t=1423237

It is my understanding that NASA has since opened up the
rules to a wider selection of D/A equipment.

.

wtknght1

Yeah, there's a lot of them out there and I'm sure they all have their good and bad points. I've used a couple of them, but the problem I have is how to properly analyze the data once you get it. Just about any system can give you good data, but the real art is figuring out what to do with it. I've just always used my 4th point of contact and the stopwatch...seems to work pretty well. Eventually I'll get one and really study it. Until then, I'll just keep my $2K and spend it on tires, brakes and rotors...and of course more seat time.

Solofast

I am using an older G-Analyst system and we record every autocross run that we do, in particular during test sessions. We then compare who had more g's where and I have a program that manupulates the data to get "relative speed". I believe that the Gtec has the ability to read RPM's, which you can turn into a speed signal and that would be an important help, but it still doesn't tell the whole story.

The biggest problem with G-G sensors is that yaw fools them and there isn't a "path" so you can see who was wider where. If you have the location and speed you have the whole picture, if you just have G's you are flying a bit "blind".

If you want to get serious about data collection I strongly recommend getting a GPS based system, or one that has in integrated GPS signal in the package so that you can determine line versus time effects. I have been holding off getting a replacement for the GAnalyst until I can afford something with GPS....

The ultimate system would tap into your CAM data bus and get the g/g data, the speed signal, and the yaw sensor signal. Add that to a GPS and you would have the whole boat, you would know exactly where and why either one was faster and you would both improve. With the Gtec you will need to keep a run log and note where you felt you got off line in the run so that you can look at that part of the data and understand where you lost time due to "path difference"...

AUTO_X_AL

The GTECH is probably the most cost effective but it is by no means a complete road racing/autocross data logger. In this case may not be totally crucial to have the GPS but it sounds like it would be nice. I don't know if I would be able to justify a couple grand on equipment for "racing only". If it was something i could apply to something else it may be diffrent but I guess I will have to see how serious I really am. The gtech may still be alright. I was just knd of under the impression it would be a little more comprehensive but for $299 I guess you cant have it all. And just out of curiosity what kinds of G's do you guys pull?

Slalom4me

$2K?

My RacePak G2X was under $0.9K last year. There has been a
modest increase but it is still under $1K. Other brands in the
category are or were in the same vicinity.

Still more than the $299 retail for a G-Tech Pro RR, but the mid-range
units have features and expandability that aren't present with the
GTPRR.

I have added several sensors since purchasing my main unit, leveraging
my initial outlay.

BTW - Did people happen to notice the books mentioned in the earlier
threads? I've made the suggestion that someone should encourage
Buddy Fey to issue a new edition and price it where mere mortals
can afford it. I have Simon McBeath's book and feel it is a worthwhile
read.

.

wtknght1

Oh you can get basic data acq systems for under 1K for sure, but if you want one with all the bells and whistles, then you're looking at double that price. If I get another one, it's going to do everything but drive the car for me!

jlucas

Be careful and re-read the GCR, your bells and whistles may be open to some interpretation. I've been trying to get some clarification from the SCCA technical office. If you've got questions, I'll do my best to answer them.

XPC5R

I have been using this one: http://www.race-technology.com/WebPa.../AP22Home.html

It's only about $200, and uses the same software to analyze as it's big brother, the GPS driven DL1 datalogger.

You can also trade it in towards a DL1 at a later date (which I plan to do)

Not much memory, so long track sessions are out of the question, but it will handle a day's worth of autocross runs. The analysis software is very good (even includes a video sync feature), and get's you experience with it before upgrading to the GPS version.

wtknght1

Oh I'm not talking about altering the air/fuel mix or anything like that; but I know there's a long list of options you can get for those things.

I'd like to get one that measures steering input (so I can see oversteer vs. understeer), braking input and pretty much everything associated with the track as well (multiple sector splits, extremely accurate distance measurements, etc). I'd like it to come with an in-car display for lap times, etc. I'd also like it to come with a removable card so I could just take that to the computer instead of the other way around. What's the price for a full system like that (he said as he cringes)?

AUTO_X_AL

That looks pretty tempting. Now is there a way on that logger to see throttle position or engine RPM's? I noticed that one really Dosen't have a direct link to anything on the car. That will make the decision a bit harder. You guys with the GTECH is the engine rpm's a the only thing to tell throttle input or is there like 0-100% bar on either system? Im sorry if I sound stupid I have no prior dealings with any data logger whatsoever. Thanks again guys.

Al

Sidney004

The GTech is strictly RPM, it does not monitor throttle angle. It determines the RPM through the electrical input or interference thru the cig lighter. Theoretically, this should be very accurate, but requires a calibration with your car. That being said, the shift lights on my GTech are not terribly accurate. I like the toy and find it valuable in gauging the Max G levels during a session.

Solofast

The really interesting thing is that everything that you need or could want to measure, except GPS position is all in your C5 already, it's on the CAN data bus. Steering wheel position, throttle position, distance, acceleration (both fore and aft and lateral), speed, rpm, and even yaw angle are all on the data bus and could be read out if you had a system to do that. Then all you would need is a GPS system and you would have the whole migilla, and GPS receivers are pretty cheap now too...

I would think that somebody who was a computer wiz could get it all together and could sell a pretty amazing system for not much money at all. If somebody did that I'm sure that everybody dialed into this forum would have one in a heartbeat... You just need a data bus reader and a way to store the data on a palmtop, heck I bet some palmtops already have GPS in them...