Boys & Girls go out to play.....

Paul Thompson 'Hooligan' · 07-16-06, 05:58 PM

Hi all -

Last Friday, Club members Bjorn Arnils and Nadine Geary ventured to Santa Pod for a 'test n tune' day....

£50 entry fee - max 100 cars - as many runs as you want - no queues....!

A few pics from the day are below...

Guess who won.....

Video will follow shortly.......

Malcolm · 07-17-06, 02:49 AM

Well in theory Nadine should win but I understand she likes to burn lots of rubber which may give it to Bjorn?

Paul Thompson 'Hooligan' · 07-17-06, 04:30 AM

True Malc -

but Nads also has 700BHP + 700ftlb in what? 1800Kg??

vs

Approx 375-400HP in about 1250Kg with ATB Diff and 3.88 UN1 + Fresh Hoosier Slicks....

Still reckon on Nads?

JP · 07-17-06, 05:41 AM

The viper won it I guess.

Loads more torque and higher bhp/ton.

Nice pics!

Keith Hardy · 07-17-06, 08:13 AM

The '40. Better traction and possibly superior 60' time gave it the edge at the finish line. Viper played catch up but didn't quite make it, despite the awesome display of rubber destruction.

Just a wild guess though.....

Hiya JP, how's your 40 going?

Paul Thompson 'Hooligan' · 07-17-06, 09:07 AM

Hi James / Keith

All will be revealed when I post the video - hopefully tonight IF I can find the firewire lead..

There were some quick bikes there too.... One, ran a 6.3 at 216Mph!!

Brave? stupid? - now that must be some bike....!

Paul Thompson 'Hooligan' · 07-17-06, 07:02 PM

To watch them run - follow the link

http://www.gtd40club.co.uk/Video.htm

:p

'We need more cylinders boys!!'

Malcolm · 07-18-06, 02:53 AM

Now that should fire them both up for the Brighton Speed Trials. Santa Pod has a grippier start line but even so Bjorn's time is cracking! And Nadine must have saved £50 on tyres with that good start. Could she haave been quicker if her reaction time was better or were they not running the Xmas tree lights? A fun day out.

Paul Thompson 'Hooligan' · 07-18-06, 04:26 AM

Hi Malc -

They were running the lights, but timing starts from when wheel first moves. Reaction time given but not counted in timing.

Apparently a reaction of less than 0.5s is classed as jumping/pre-empting the lights... and a fail???? - seems odd to me but I guess they want you to go once you see the green, not guess when the green will hit?

Maybe some of our experienced friends over the pond can elaborate on how the timing system usually works.

JP · 07-18-06, 04:48 AM

Torque wins.

JP · 07-18-06, 04:50 AM

Quote:

Originally Posted by Keith1

Hiya JP, how's your 40 going?

What 40? I got out of it about 2 years ago!!

Still got a 550hp Dart engine, so who knows!! Maybe...

Tod · 07-18-06, 12:15 PM

Quote:

Originally Posted by p thompson

Hi Malc -

They were running the lights, but timing starts from when wheel first moves. Reaction time given but not counted in timing.

Apparently a reaction of less than 0.5s is classed as jumping/pre-empting the lights... and a fail???? - seems odd to me but I guess they want you to go once you see the green, not guess when the green will hit?

Maybe some of our experienced friends over the pond can elaborate on how the timing system usually works.

My knowledge is not extensive, and I may be wrong, but the .5 seconds is the amount of time it takes the last yellow light to turn green. Anyone leaving before that "Red Lights".

Keith Hardy · 07-18-06, 02:54 PM

Quote:

Originally Posted by James

What 40? I got out of it about 2 years ago!!

Still got a 550hp Dart engine, so who knows!! Maybe...

Not that one, the red one!

Bugger, this is getting confusing. JP I meant the red (40) CAR (not light)! Sorry about thread drift. Last time we saw it, it was a tad crispy, yes?

Ron Earp · 07-18-06, 03:45 PM

On a full tree the delay between the yellow and green is 0.5s. On a Pro tree it is 0.4s. You'll cut a perfect light if your reaction time matches these, and you'll red light if you cut the beam shorter than this time. Here is a primer:

http://www.staginglight.com/guide/react.html

On that race I sort of thought it'd end badly for our GT40 hero. I think Vipers weigh in much less than the predicted 3960lbs in the eariler post. I think around 3400lbs is more in line, so around 1500 Kg? So the real weight difference might be around 550 lbs or so, but the difference in torque is probably what - 300 ft/lbs throughout the entire rev range, not to mention the difference in hp......

TMM · 07-18-06, 03:49 PM

Paul and all,

My friend with a Roaring 40's GT asked me to help answer some of the questions re: drag strip timing. My name is Dave McClelland and I have been announcing races for some 50 years....NHRA National Events since 1961. Have watched lots of runs!!!

First the track...1320 feet from starting line to finish line. Timing is controlled by infrared beams across the track at the starting line, 60', 330', 660' or 1/8 mph; both elapsed time and speed, 1000' e.t., and quarter mile e.t. and speed.

The clock is not controlled by the starting line system, or christmas tree. That device is used to actually motivate the drivers into leaving the line. The clocks begin operating the moment the front tire leaves the starting line beam.

The question regarding reaction time is answered by noting the tree has nothing to do with the timing of the cars. The yellow light is either 3 bulb or single...depending upon the category of competition, at least here in the states. In the full or 3 bulb mode, each yellow light is on for .5 of a second before the tree goes green. That is used in sportsman competition, except T/AD, TA/FC, Super Comp, Super Pro and Super Street. It is designed to allow the driver to anticipate the actual green light...as opposed to the single bulb, or Pro Tree used by T/F, F/C, Pro Stock and P/SMcycle/ That is generally referred to as a reaction starting device. Currently, stateside the duration is .4 seconds...as opposed to the .5 that was used up until a few years ago.

In the case of the full tree...you are not responding to the green light, but launching on the second or last yellow light...depending on how your car leaves the line. Reacting to the yellow is also possible in the Pro start mode, if both car and driver are quicker in reaction that the length of time
(either .4 or .5) of the yellow light. Pro Stock Motorcycles immediately come to mind...and that also explains the number of red lights in that category.

Bear in mind, the reaction time readout is in reality, a combination of both the driver's R.T. and the way the car responds to the launch. That's why so much emphasis is made on getting the car to work better.

There have been changes in recent times, made to the way reaction time is displayed on the screen. If the screen or printout shows a .510...that indicates the driver had a light of .010 before red lighting...anything .499 and under is a red light. If the screen showed a .010...that would be representative of the later type of display...but revealing the same reaction time. That would mean anything reading .999 or less is a red light in that mode.

As the car makes its way down track, the breaking of the infrared beams triggers actions in the timers, giving the readout for the distances mentioned above. This allows the driver/tuner/crew chief to determine the consistency of the car...the place where work is needed to improve performance...or in some cases, tear their hair out because nothing seems to work!!!! The latter is more frequent that you would imagine.

One major point to remember...each individual lane is timed separately...thus leading to the situation where the quicker car can lose the race to a slower one because of better reaction time. That's why driver and crew work so hard to improve on reaction times. Bear in mind, if one car leaves first, the other could sit there for an hour and the clock would not start until it leaves the line.

Hope I haven't bored you with all of this but it's about as concise as I could make it and still try to explain how it all works. When you are announcing in the tower, you get the sight of the progressive times coming up on the screen, so thus you can sound like you really know what you're talking about!!!

My best to all and stay safe.

Dave McClelland

Malcolm · 07-18-06, 05:49 PM

Bjorn clearly took this badly but I will let Paul or Bjorn explain.....

Paul Thompson 'Hooligan' · 07-18-06, 06:50 PM

Thanks Dave for the most excellent explanation.... All is now clear!

Quote:

Originally Posted by Malcolm

Bjorn clearly took this badly but I will let Paul or Bjorn explain.....

Actually Bjorn did'nt, but after Nadine let both Bjorn and I have a drive of her Viper on Friday, (and believe me it's SAVAGE!!

) we were both smitten!

Bjorn especially so, to the point that he collected a superb GTS today to add to his collection and both he and Nads are off to Silverstone tomorrow to 'play'.....

Have Fun!!!!