202 MPH!!!! in the DMS tuned Gt2

[R1_JON]

Simply awesome

[m12_nathan]

I was in your car for a 193 run - was savage, the needle flys to 7k rpm so quickly, very impressive conversion and congrats on the 200 club!

[CraigBruce]

Well done! Presume the DMS work was more cost effective than what I expect the soon to be owner of that 9ff must be paying!!!

[dazren]

Outstanding.

[Guyr]

Daz,

I see in the results thread you have posted that the timing beam read much higher than your GPS - is my interpretation of your posting correct?

Guy

[CraigBruce]

Don't know about Daz, but my PerformanceBox matched the timing beams in the morning session, where I was repeatedly hitting 183/4. In the afternoon session with the extra distance I was finding that the beams were reading 3/4mph higher than the GPS PerformanceBox (my 191 was indicated by the beams, with 187 ish...need to check...on the GPS). At higher speeds I suspect the GPS may be less accurate as it is only sampling every 10th of a second and will be dependant upon the numer of satellites in view and the processor speed of the unit.

...or perhaps I'm just happier with the higher speed on the beams :-)

[Weltmeister]

Craig
I checked back to the previous V-Max. Your car ran 187 then. I also checked on a few other cars for "Benchmarking".

1]Derestrictor M6 186 MPH last time vs 187 MPH this time
2] R1_Jon 996 GT2 186 last time vs 183 this time
3] Craig Bruce 187 last time vs 191 this time

Looks like the car is just faster.

Allan

[ThatPhilBrettGuy]

CraigBruce said:

At higher speeds I suspect the GPS may be less accurate as it is only sampling every 10th of a second and will be dependant upon the numer of satellites in view and the processor speed of the unit.

Sorry to say this, but I know the hardware of those VBOX's (which the Performance Box is) very well. It'll be spot on assuming you're looking at the log data after the fact. Remember a 10th of a second sampling is 10 times the rate satnav and pocket GPS's calculate their speed, and they are usually within 1 mph of the laser trap.

If everyone's speed jumped in the afternoon and the wind didn't start blowing like mad, even moving the beams 1/4 mile or more wouldn't account for the increase.

Edited by ThatPhilBrettGuy on Sunday 19th August 23:07

[LuckyP]

Have the same concern about the timing in the afternoon session.

I set my own speedo to GPS and it's spot on. In the morning my speedo concurred with the readings on the board, in the afternoon, I was getting the car to just over 180.....but not the 188 seen on the timing board.

I hope I'm wrong, and if I'm not, I hope it was only the LHLane....otherwise, Leon still holds the record!!

Lucks

[neil_bolton]

LuckyP said:

Have the same concern about the timing in the afternoon session.

I set my own speedo to GPS and it's spot on. In the morning my speedo concurred with the readings on the board, in the afternoon, I was getting the car to just over 180.....but not the 188 seen on the timing board.

I hope I'm wrong, and if I'm not, I hope it was only the LHLane....otherwise, Leon still holds the record!!

Lucks

That may explain the 4 mph extra I managed on my very last run in the dry - I was in the left lane; I'd been in the right up until then...

However, it said 140mph and for me that'll do

[Guyr]

Sorry if I sounded like I wanted to add a doubting voice to the debate, it's just that some of the speeds quoted look a little high and it seems that others have also found that out from their own devices.......

I see from the other threads that both LuckyP and Blue Satin experienced about a 6mph incresae in speed in the left lane vs the right lane at the end, this does suggest something is amiss.

In future, would it worth getting the timing calibrated by an accurate GPS (ie Racelogic or VBox with a 5Hz or 10Hz sample rate). I know in the the past I have calibrated the timing with my Racelogic and it's been within 1mph to true, so it seems like an error has crept in this time.

Edited by Guyr on Sunday 19th August 23:08

[goodlife]

It does appear that there was an error on the left lane timing gear after the beams were moved further back after lunch. However the afternoon speeds were definately higher anyway, as the weather gave very favourable Vmax conditions with a gusting tailwind and low air temperatures. IIRC the 9ff used the RIGHT lane for both it's roof down and roof up runs.

[Dangly]

The 211mph speed was in the right lane depending on how you look at it.

See pic

hmm that didnt work....MS Paint then



Got the skills!

Edited by Dangly on Monday 20th August 00:01

[markbe]

LuckyP said:

Have the same concern about the timing in the afternoon session.

I set my own speedo to GPS and it's spot on. In the morning my speedo concurred with the readings on the board, in the afternoon, I was getting the car to just over 180.....but not the 188 seen on the timing board.

I hope I'm wrong, and if I'm not, I hope it was only the LHLane....otherwise, Leon still holds the record!!

Lucks

At the last Vmax I spoke to the timing chap he was telling me the timing beams have to be 29' 4" apart to be accurate. Maybe when they were moved
they were less than that giving the higher readings.

Mark.

[R1_JON]

I think the left lane was definitely over reading a little. All my afternoon runs were in the right lane at the normal speeds and pretty consistent with Daz and Bluesatin's normal speeds, yet their left hand lane runs were quicker.

[NoelWatson]

I was hitting the limiter in 5th (geared for 160 in NSX) just after lunch in the left hand lane and the timing beams showed 160 and 159 - so it didn't appear to inaccurate at my admittedly slower speeds - I hit 156 before lunch and was some way short of the limiter, so I didn't see anything unexpected when comparing the before and after lunch measurements.

[trackdemon]

NoelWatson said:

I was hitting the limiter in 5th (geared for 160 in NSX) just after lunch in the left hand lane and the timing beams showed 160 and 159 - so it didn't appear to inaccurate at my admittedly slower speeds - I hit 156 before lunch and was some way short of the limiter, so I didn't see anything unexpected when comparing the before and after lunch measurements.

Thats consistant with the 160mph my '95 3.0 got a couple of years ago........ bl00dy gorgeous car BTW, I meant to have a chat with you but never got around to it. That colour just looks so damned good.

[neil_bolton]

trackdemon said:

NoelWatson said:

I was hitting the limiter in 5th (geared for 160 in NSX) just after lunch in the left hand lane and the timing beams showed 160 and 159 - so it didn't appear to inaccurate at my admittedly slower speeds - I hit 156 before lunch and was some way short of the limiter, so I didn't see anything unexpected when comparing the before and after lunch measurements.

Thats consistant with the 160mph my '95 3.0 got a couple of years ago........ bl00dy gorgeous car BTW, I meant to have a chat with you but never got around to it. That colour just looks so damned good.

I have a cracking picture of the NSX wheelspinning (with smoke) at the start of the run - I'll post it once I've processed it

[CraigW]

I checked both lanes post lunch, both concurred with my gps readings

[outnumbered]

Lots of conflicting evidence then.

I was also getting slightly higher speeds in the left hand lane in the afternoon, but put it down to:

- drier track
- stronger tailwind
- cooler conditions for fastest run
- left lane giving the most consistent opportunity to use all the runway coming out of the bottom bend (exit speed from this corner makes a big difference for me)

I guess we'll never know now... But at least the 9ff's 211 seems pretty uncontestable, in the right lane ?

Perhaps an argument for doing a calibration run using a known-accurate GPS in future ?