GPS timing the mile, continuation...

[BlackICE]

21 PSI pulley but because of the thin air logged boost was about only 18 lbs. At sea level with a 19 PSI pulley, but during a dyno run logged boost between 19 and 21 got 745 HP. Dyno don't mean sh*t. What counts is what happens on the road. The thin air at Mojave makes the dyno number almost meaningless. At TX the hot temps cause my tune to pull timing back to only 10 to 11 degrees during the end of my runs killing power, also dyno numbers meaningless.

I did 188.5 at Mojave and 180.2 in TX. I only know of 2 Whipple only cars (no NOS) that did a timing 200+ in the standing mile, both at TX. I believe the both ran with tailwinds. IMHO it will be damn tough for a Whipple only car to do 200+ at Mojave, unless you have cool temps and a BIG tailwind. Looking at my data I could have drove better at Mojave, in which case I think the car could have done 190-192. A far cry from 200 under those conditions.

I am planning a few more mods so that if conditions are good (tailwinds, cool temps) I might have a chance for 200+ at Mojave.

 

[Fast Freddy]

21 PSI pulley but because of the thin air logged boost was about only 18 lbs. At sea level with a 19 PSI pulley, but during a dyno run logged boost between 19 and 21 got 745 HP. Dyno don't mean sh*t. What counts is what happens on the road. The thin air at Mojave makes the dyno number almost meaningless. At TX the hot temps cause my tune to pull timing back to only 10 to 11 degrees during the end of my runs killing power, also dyno numbers meaningless.

I did 188.5 at Mojave and 180.2 in TX. I only know of 2 Whipple only cars (no NOS) that did a timing 200+ in the standing mile, both at TX. I believe the both ran with tailwinds. IMHO it will be damn tough for a Whipple only car to do 200+ at Mojave, unless you have cool temps and a BIG tailwind. Looking at my data I could have drove better at Mojave, in which case I think the car could have done 190-192. A far cry from 200 under those conditions.

i thought Godzilla didn't need traction control......

op

 

[skyrex]

Elevation is not ideal at Mojave, but I do think the weather was a factor also. It is a good bet the weather will be better in September and we will have two days to sort out our runs instead of one so I think we would have all improved regardless of our upgrades.

Plus the wind usually shifts later in the day so we should have tail winds for part of the time.

Are you guys planning on doing both days??

 

[BlackICE]

i thought Godzilla didn't need traction control......

op

TC is nice, but IMO of limited value in the mile. I think it would play more dividends on a TT where you can maintain the boost without a lost of control. That said, it did give me great peace of mind, such that I could bury the throttle without worry. The tires were slipping but under control with the 3.9 gears. Without the system on the cold condition at Mojave would have my tires lit up through 3rd with the stock GY tires.

Apollo was the fastest street car at Mojave with a 189.2. He has a Gen 3, 4L Whipple. He finally joined the 200 club by using a little more road. This is another bit of information that supports the 200 club is difficult with only a Whipple. Of couse this was done at sea level not at 2700'. Tanner Foust did 206 borrowing a ride in a Whipple with 23 PSI pulley and water injection. That car is reported to have dynoed at 850HP.


http://www.fordgtforum.com/forums/showpost.php?p=225970&postcount=37

From the link:

We saw a FGT break the standing mile record. Monica ran 192.9 in her first run and backed it up with a 190 . I was flirting with 200 in the mile but only got to 197... until they extended to a 1.25 and I officially have joined the 200+ club with a 202.5 and then a 201.? with Monica in the passenger seat.

 

[soroush]

my car ran 209 with no NOS, whipple only , BUT I do have built motor and ported head with different cams. my car makes about 860 on whipple alone!

 

[BlackICE]

my car ran 209 with no NOS, whipple only , BUT I do have built motor and ported head with different cams. my car makes about 860 on whipple alone!

...and MS109, 23 PSI pulley?

Soroush now I am depressed. If you with 860 HP and driving better than I ever will did 209 how is little old me going to get passed 200 at 2700' with just a Gen 1 Whipple?

 

[Fubar]

I'll get 200 out of a whipple and I'll do it on pump gas with no NOS. That doesn't mean I don't want the NOS.

 

[Fast Freddy]

I'll get 200 out of a whipple and I'll do it on pump gas with no NOS. That doesn't mean I don't want the NOS.

now that is what i am talking about :cheers

 

[Yukonranger]

Freddy is right but the problem applies whenever timing is used to measure speed (not just GPS). When time is used to measure speed the result is always the *average speed* over the distance measured. There is no way to know the exact speed at any point using timing though the error gets smaller as the distance get smaller. At over 200mps the vehicle travels close to 30 feet between updates at 10Hz, obviously 6" between timing lights would be more accurate.

GPS adds another variable in that the position is subject to greater error than measuring directly. If the GPS position accuracy is + or - one foot then the distance traveled between updates is + or - two feet. Unfortunatly this becomes a bigger problem as the distance interval you are measuring goes down.

The only way to measure speed with perfect accuracy is to bounce a particle off the vehicle and measure the change in energy of the particle. Even then, as Werner Heisenberg pointed out long ago, just bouncing the particle off the vehicle changes the speed of the vehicle. In reality, the error can be reduced to very small levels with any timing scheme (including gps) with software but the result remains an approximation.

YOU FAIL

go back to physics class and then go talk to the Chief tech of timing and scoring at Bonneville and mail your check to me overnight :lol

 

[centerpunch]

Why are vBox's considered such a good device for measuring 60-130 and track lap times?

I researched this very thoroughly when I developed the G-Timer products for Escort several years ago.

The VBOX does NOT use the GPS location data to calculate speed, it works in a totally different way that makes it VERY VERY VERY accurate. Formula One teams would not use it if it didn't work!

The VBOX calculates doppler shift from the signals from the geostationary GPS satellites and calculates velocity from that.

Bottom line, the VBOX is amazingly accurate, at any speed and any acceleration.

http://www.racelogic.co.uk/?show=VBOX-Accuracy

http://www.racelogic.co.uk/?show=VBOX-Misc-Customers

 

[jaxgt]

Centerpunch - which of their products use this technology: driftbox, performance box or vbox or all?
Thanks

 

[soroush]

...and MS109, 23 PSI pulley?

Soroush now I am depressed. If you with 860 HP and driving better than I ever will did 209 how is little old me going to get passed 200 at 2700' with just a Gen 1 Whipple?

on pump gas, with the 21 lb pulley car is seeing 20lb of boost. we never dyno'd my car or tuned it for race gas, everytime I want to run NOS I just put in 5 gallons of 109 other wise Im good to go

 

[centerpunch]

Centerpunch - which of their products use this technology: driftbox, performance box or vbox or all?
Thanks

They all do.

Car and Driver confirms that the Driftbox results matched their multi-thousand dollar VBOX.

http://www.caranddriver.com/features/06q3/the_racelogic_driftbox-tech_stuff

 

[jaxgt]

Seems like for those who don't specifically do drifting (ie me) that the Performance Box is a nice addition to the car for mile or track events. Thanks

 

[BlackICE]

Thanks Centerpunch. That explains why my Driftbox data match VERY closely to the timeslip giving to me at the TX mile. The real numbers matched better than the 2nd decimal place, or 5 significant digits! I didn't really believe that match would be that close! Of course that assumes you have a good lock on enough satellites to get those results. I think that close of a match is a fluke since the guy setting up the timing lights spaced 100' apart would have to get them within 0.12". More chance of errors there than in a Driftbox. :biggrin

 

[BlackICE]

Seems like for those who don't specifically do drifting (ie me) that the Performance Box is a nice addition to the car or mile or track events. Thanks

That is correct, but check around, Hennessey sold me a Driftbox for only a little more that a Performance Box. :thumbsup

Never know when you may take up drifting your FGT. You can let Tanner Foust do it for you. :lol

 

[ivanrho]

Gentlemen,

The oldest and most experienced entity conducting this type of event is the Texas Mile. Their method of timing which calculates an average speed at the end of the mile over a fairly long last segment of the course, results in a lower final speed for high-powered cars that are still accelerating hard at the end of the mile. The timing equipment used at the Miami Mile, assuming it is properly set up and calibrated, would issue a higher speed calculation than the equipment used at the Texas Mile for two high-powered cars running identical actual velocities.

Chip Beck
Moderator
Ford GT Forum

Chip,

I disagree with your statement here. Before the Texas Mile ever existed, there was and still is the ECTA. They've been around for over 15 years, and follow stringent rules for Land Speed Racing, just like those of Bonneville and are regarded as the ones to model after.

When TOP GUN RUN in Miami put together their timing methods, it was based on the way Maxton Mile is run. The Mile is surveyed and at the end of the mile, you measure back 132 feet. It is at that point that you place your 1st beam, and at the end of the mile, the 2nd beam. Keith Turk and Joe Timiny are friends and have assisted in the setting up of the timing equipment in Miami for TOP GUN RUN.

The MPH is calculated using a formula that is based on the time it takes you to cross the 1st beam, and then the 2nd beam. The machine, after each run spits out a receipt that shows the seconds to the 10,000th and then a MPH.

As I may have mentioned before, TOP GUN RUN uses the latest in Tag Hauer timing equipment provided by the same people that provide it to Texas. In fact, Texas is still using the same equipment since 2003. TGR is using a newer model that is more accurate and reliable. (PM me if you wish to have the supplier name and number)

That being said, TOP GUN RUN has close ties with the ECTA and is currently is discussion to holding joint Mile Events this fall and winter and as well having them run ALL the timing at each event so there is absolutely NO QUESTION or loss of faith; times will be ironclad. (All ECTA Members were invited to participate in our past March Event through Keith Turk)

 

[ChipBeck]

A few questions.

Chip,

I disagree with your statement here. Before the Texas Mile ever existed, there was and still is the ECTA. They've been around for over 15 years, and follow stringent rules for Land Speed Racing, just like those of Bonneville and are regarded as the ones to model after.

When TOP GUN RUN in Miami put together their timing methods, it was based on the way Maxton Mile is run. The Mile is surveyed and at the end of the mile, you measure back 132 feet. It is at that point that you place your 1st beam, and at the end of the mile, the 2nd beam. Keith Turk and Joe Timiny are friends and have assisted in the setting up of the timing equipment in Miami for TOP GUN RUN.

The MPH is calculated using a formula that is based on the time it takes you to cross the 1st beam, and then the 2nd beam. The machine, after each run spits out a receipt that shows the seconds to the 10,000th and then a MPH.

As I may have mentioned before, TOP GUN RUN uses the latest in Tag Hauer timing equipment provided by the same people that provide it to Texas. In fact, Texas is still using the same equipment since 2003. TGR is using a newer model that is more accurate and reliable. (PM me if you wish to have the supplier name and number)

That being said, TOP GUN RUN has close ties with the ECTA and is currently is discussion to holding joint Mile Events this fall and winter and as well having them run ALL the timing at each event so there is absolutely NO QUESTION or loss of faith; times will be ironclad. (All ECTA Members were invited to participate in our past March Event through Keith Turk)

Ivanrho,

Until you mentioned it here, I had never even heard of the ECTA (East Coast Timing Association). But then again, I live in Arizona. I looked at their website and their events look a lot like the Texas Mile but with fewer exotics and a lot more highly modified coupes, sedans, and trucks. I understood that the beams at the Texas Mile were spaced farther apart than the beams at TGR. Are you telling they are both 132 feet? If that's the case, why makes the new Tag Hauer equipment more accurate? What is different? Thanks!

Chip

 

[ivanrho]

Ivanrho,

Until you mentioned it here, I had never even heard of the ECTA (East Coast Timing Association). But then again, I live in Arizona. I looked at their website and their events look a lot like the Texas Mile but with fewer exotics and a lot more highly modified coupes, sedans, and trucks. I understood that the beams at the Texas Mile were spaced farther apart than the beams at TGR. Are you telling they are both 132 feet? If that's the case, why makes the new Tag Hauer equipment more accurate? What is different? Thanks!

Chip

Hey Chip,

ECTA is really about the true sport of Land Speed Racing, where they have many different classes and you race against other people in your class to earn points. When I was there last year, the participants' cars were nothing like the ones we're used to seeing here in Miami or even Texas, but they were every bit motivated, maybe even more. It's not only passion that I witnessed, it was almost cult-like.

Most exotics would never be able to run at Maxton, because of their rules and regulations; unfortunately I don't think our friends here are willing to chop up their cars for those rules, but safety is paramount and should be considered carefully, yet we think nothing can go wrong because it hasn't yet.

I don't know what distance Texas uses for their timing, but TOP GUN RUN does it exactly the way Maxton Mile does.(ECTA) As far as the equipment goes, it's just newer technology; more accurate and more reliable, according to the supplier.

BTW, our friend Bill from Tampa just put down a 272 MPH in a Turbo Hayabusa at Maxton. A new record for that class. He told me he will be at the next TOP GUN RUN event in Miami in hopes of going even faster.

 

[jaxgt]

ivanrho - when is the next topgun run event?