GPS Units To Measure HP

[jfawsitt]

There has been some discussion on the NE Region Forum about NASA National's adoption of GPS Units made by Trackmate to measure Horse Power next season for all regions. From what I read some real units and some dummy units will be placed in cars at the grid by the region. Does anyone know if GTS will be included in this?

 

BTW I got my car back after the July Mid-Ohio Crash Repairs. I had a great weekend at the Glen with NE Region the 1st of Oct and finished the season off with Mid Atlantic Region at VIR last weekend. Looking forward to next year.

 

Joseph Fawsitt

Porsche RS America

025 GTS3

[ianacole]

We are discussing further testing of the applicability of these types of units to monitor compliance. We are not ready to implement this as a standard practice.

[jrgordonsenior]

We are discussing further testing of the applicability of these types of units to monitor compliance. We are not ready to implement this as a standard practice.

 

Ian what was the consensus on the units used at Miller last month? I know one lived on my car every time I went out, but I never was told in absolute terms how the results measured up against my Miller dyno's. Curious.....

[ianacole]

We are discussing further testing of the applicability of these types of units to monitor compliance. We are not ready to implement this as a standard practice.

 

Ian what was the consensus on the units used at Miller last month? I know one lived on my car every time I went out, but I never was told in absolute terms how the results measured up against my Miller dyno's. Curious.....

 

Mixed bag ... we had some that were exactly as expected, others that were off. Further testing will reveal their useability and the process we need to employ to measure, if/when it comes to that.

[cwbaader]

Major problem...as the fuel burns off, the horsepower will rise due to the lighter weight. You would have to average the HP over the run, and only on level ground because my 140HP wonder makes 175 going down hill!!! CB

[Eric W.]

Major problem...as the fuel burns off, the horsepower will rise due to the lighter weight. You would have to average the HP over the run, and only on level ground because my 140HP wonder makes 175 going down hill!!! CB

 

Fuel burn shouldnt be an issue since that is supposed to be accounted for anyways. At the end of the race, with fuel burned, you still need to make weight.

 

However, being downhill does matter and I believe this is accounted for by looking at data on a flat and straight portion of the track.

[911.racer]

And areodynamic drag.

 

If I have my wing turned all the way up or all the way flat it has a dramatic effect on what the reading would be on my 140Hp car.

 

I would be happy to take part in trials and to help test units in others cars too to help further the development of this.

 

Thanks

 

Ed Baus

[jfawsitt]

I would also be interested to be involved in the testing of units next season. This can only be a good going forward if it can be perfected.

 

JF

[Eric W.]

And areodynamic drag.

 

If I have my wing turned all the way up or all the way flat it has a dramatic effect on what the reading would be on my 140Hp car.

 

Ed Baus

 

Yea, but if you did that to try to trick it, then whatever session you ran in would SUCK. I believe the goal is to put a number of these units into service along with dummy units. You wouldnt know when you had one in the car, so if you turned up your wing all the way, your qualifying and/or race times would suffer.

[911.racer]

If I would balance the front I would be the KING of the corners.

[John Graber]

I agree and support putting GPS units in Eric's and Ed's cars......

 

Is there a PayPal address where we can send $20 to fund the project?

[rabbit_diesel]

Particularly look at the HP readings while the car is going at a relatively slow speed, such as coming out of slow corners. This way, the aerodynamic drag would have a negligible effect.

 

With before and after weights of a race, and the HP vs. time data, the average lb/(hp*hr) fuel burn rate can be calculated. This figure will allow for a good estimate of the weight of the car at any time throughout the race.

 

Furthermore, each set of data recorded for a particular car and driver and track, will be rather like a fingerprint. Every subsequent race can be compared to all the previous races, and if any large discrepancies show up, then the inspectors will KNOW there is something to be looked into.

 

Will

[Sterling Doc]

John, my data from Putnam's posted on the MW & Rennlist forums - you can give the $20 directly to me.

 

We been looking into this, too. Problem is, the racetrack is not a lab, and trying to measure the difference 5 hp makes in accelerating a 2,600 lb (in our case) car, in this environment, at the moment it makes peak power, is not a very precise or repeatable measurement. Look at the data below. It's a bit messy, since it's the HP plots of all the laps in one race of 3 cars, that all made 131 +/- 1HP on the dyno at Putnam. Their respective weights were figured in. Can you tell how much HP they make based on the data below? It's hard - lots of lap to lap variability, and it's not linear as the fuel burns off. Pretty fuzzy fingerprint.

 

[John Graber]

I meant Wong

[Eric W.]

I meant Wong

 

My AIM doesnt show HP, and Im not savvy enough to figure it out. I did do this once when I drove Jim Khoury's car though. Suprisingly his slower laptime yielded a higher HP plot.

 

[rabbit_diesel]

We been looking into this, too. Problem is, the racetrack is not a lab, and trying to measure the difference 5 hp makes in accelerating a 2,600 lb (in our case) car, in this environment, at the moment it makes peak power, is not a very precise or repeatable measurement. Look at the data below. It's a bit messy, since it's the HP plots of all the laps in one race of 3 cars, that all made 131 +/- 1HP on the dyno at Putnam. Their respective weights were figured in. Can you tell how much HP they make based on the data below? It's hard - lots of lap to lap variability, and it's not linear as the fuel burns off. Pretty fuzzy fingerprint.

Interesting set of graphs. Having looked at them and thought about it for a little while, I suspect that plotting HP vs. distance is not going to produce a useful result.

 

What I would be interested to see is: a plot of HP vs. MPH, of all laps of a single car, for the section of track immediately after a slow turn where one exits and generally goes full throttle (such as turn 7 at Road Atlanta), on up to about 100 MPH or so; and the same plots for the other two cars. (It may turn out that one does have to apply a correction for the decreasing weight of the car, in order to improve the accuracy of the data. Even without the correction, I imagine the plots will be interesting.)

 

Will

[Eliminator]

To eliminate aerodynamics, the proper WHP readings would be taken at sub 85mph speeds.

[pokey100]

I am thinking that no matter how inaccurate the GPS system is, it can probably determine that Ed and John's cars are running between 25-40hp more than 140hp on the track.

 

Pokey

[Sterling Doc]

Wow, care to back this up, Pokey? Having raced on the same track/time as those guys with my 131 RWHP 944, their accelleration is suprisingly similar.

[pokey100]

I have been on the track with them as well. I guess I should have included Eric in my list of cars easily measured with GPS with greater hp than claimed.

[ernie j]

I AM IN FOR $20.

[pokey100]

Not sure why you need a GPS measurement when there are random dyno's??? Why can't we play by the rules? Who can we trust these days? Lets bring back Charlie!!!

[Michael G.]

It all depends on where you are. In your Region it may be available for random test - in our (NE) - it is hardly ever available! So, in order to enforce the rules (or how you put it - "play by ones") - GPS units may give us that chance, hopefully.

Michael G.

(NE GTS Director)

[911.racer]

Wow, care to back this up, Pokey? Having raced on the same track/time as those guys with my 131 RWHP 944, their accelleration is suprisingly similar.

 

Thanks for having our back Eric, but if my guess about who Pokey100 is, he is just fooling and I have the video to prove it.

 

 

Eric W's comment about 85mph will not work so well for me though. I am making significant downforce at 85mph. Heck my cars terminal velocity is 118 down the mid o back straight. My car with the splitter and wing is going show much less than dyno hp as directly compared to Eric K's stock bodied car. (I am guessing) More than willing to send on my chasecommander data to someone who can compare and contrast that and maybe try to turn the data into Hp.

 

Just as a quick check though, I assume Eric's motor makes roughly 140 hp compared to my 143. I assume that he has a stock transmission with all stock gears and short 5th like he is allowed to do as compared to my ... expensive transmission. My suspension costs a bunch more giving me a bit of a solid run out of the corner. My highest speed at the end of the back straight and Mid O is 118mph, Eric K, what is yours.

 

 

Coming out of the corners is not so good either because I would not be in the rpm band range to be at peak.

 

This is a great idea for cars making 500 hp where 7hp does not do much, so you are looking for something more like a 5% change or 25hp , but with a whopping 143hp/tq on the windshield the device needs to have almost no noise or outside interference to work well. And, car to car comparison is very difficult with different downforce.

[John Graber]

Are you talking US Horse Power or Canadian Horse Power?

 

You can see the effect of drag in this video. Clearly my large rear wing has slowed down my top speed a little against a car with a small rear spoiler.......