Standing mile estimation

[db484bhpv8]

I am thinking of having a go at the standing mile soon.
There is an event coming up at Elvington and i think it will be worth taking the day off work.

I now have the gearing with the 3.08 diff and will be using a healthy shot of nitrous (maybe 150).

Does this sound plausable?
1/4 mile in 12 @ 120
1/2 mile in 19 @ 150
full mile in 30 @ 175

[RichardD]

What bhp are you running at nowadays? More than 370 ATW ?

I assume the run would be on normal tyres (not the MT rubber) ?

[db484bhpv8]

I think i would be on the RSRs hence 'only' 12 to the 1/4.
I would be happy yo try it on the MTs tho.

NA i have about 275 @ wheels, then was thinking a 150 shot to give me another say 125 so 400 @ wheels.

[ChilliWhizz]

Numpty question Derek, but is the nitrous 'on' from launch to finish?

[RichardD]

The numbers earlier should be very close.

With a 2.2 60 ft time (assuming OK on normal rubber) being 11.9 @ 125, the 1 mile vMax is do-able .

[brett84]

I saw a documentary a while ago which might help
http://www.youtube.com/watch?v=odwnpFwuwF8

[db484bhpv8]

ChilliWhizz said:

Numpty question Derek, but is the nitrous 'on' from launch to finish?

Far from a numpty question Chilli.
I wouldnt want to use it thoughout the run but may need to most of the time to achieve the goal.
A passenger carefully watching the AFR and temps may help.

[db484bhpv8]

RichardD said:

The numbers earlier should be very close.

With a 2.2 60 ft time (assuming OK on normal rubber) being 11.9 @ 125, the 1 mile vMax is do-able .

I would think 2.2 is plenty. Just down to aerodynamics and keeping the gas flowing from a cooling bottle at the top end.
Maybe i would use one system to get the speed up to the 1/2 mile then hit it with a fresh hot bottle for the last 10 seconds or so

[keith2.2]

Interested to know what you've done aero-wise?

I've had mine over about 120/130 once - I only really noted the speed because I found the front suddenly go very light and the car drifted a few feet to the right. There's no WAY I'd want to try a top speed run in it.

I don't have the "splitter" underneath the front, but having seen the design, I'd be amazed if it made that much difference.

I'd also make sure I had proper bonnet pins if I was going to regularly venture into 3-figures - I presume you probably already have done!

[QBee]

db484bhpv8 said:

ChilliWhizz said:

Numpty question Derek, but is the nitrous 'on' from launch to finish?

Far from a numpty question Chilli.
I wouldnt want to use it thoughout the run but may need to most of the time to achieve the goal.
A passenger carefully watching the AFR and temps may help.

Two Spa gauges that flashed at pre-programmed levels might weigh less than a passenger.....

[fatboychim]

keith2.2 said:

Interested to know what you've done aero-wise?

I've had mine over about 120/130 once - I only really noted the speed because I found the front suddenly go very light and the car drifted a few feet to the right. There's no WAY I'd want to try a top speed run in it.

I don't have the "splitter" underneath the front, but having seen the design, I'd be amazed if it made that much difference.

I'd also make sure I had proper bonnet pins if I was going to regularly venture into 3-figures - I presume you probably already have done!

You may be surprised by the front splitter, my bonnet used to lift 5 or 6 inches at speed until I fitted one. Try pulling your bonnet up and see the force required, I know when stationary there is no negative pressure above but the splitter stops this bonnet lift . I'm not convinced about the better cornering argument but at speed it does make a difference.
I used this method, photo courtesy of haircutmike, nice fella, I wonder what happened to him.

haircutmike said:

Several people have made theirs out of cheap PVC gutter.

Mine's been on for a least 18 months.

Exuse the shameful underneath, shot taken prior to spruce up!

[db484bhpv8]

I had 158 on the TomTom at the BNG and it felt fine.

My plans for set up would be to lower the car an inch all round, stiffen the Nitrons, and to gaffer tape the roof panel.
I am confident of 165+ but anything over that would be guessing at best

[QBee]

Yes, orange Nick has lost his roof at 130 around Snetterton.

The splitter makes a huge difference, both the handling and bonnet stability, and adjusting the bonnet catch to tighten it down also helps. FWIW, if the bonnet pops open at 135, like mine did, it only comes up about 6 inches - gives the impression you are enjoying yourself...

The splitter can be obtained here if you don't fancy making one

[db484bhpv8]

to add.. i have Aerocatches fitted to my bonnet so thats not an issue.

The splitter is something worth considering

[QBee]

Please help me understand the gearing of your car versus mine.
Mine has the standard diff, and would hit the 6200 electronic rev limiter in fifth at 166 mph, I calculate (assuming my balls didn't go inboard before that)

I am doing almost spot on 80 mph at 3000 rpm in fifth gear

[db484bhpv8]

With a 3.08:1 diff and 265/35/18 tyres mine runs a shade over 30 mph/1000 revs in 5th. Atr 3000 rpm i see 91 on the Tomtom. So 175 should be had if i am near to 5800 rpm in 5th.

Before anyone questions the acceleration being affected.
I ran a 10.8/129 1/4 mile last weekend. I was at 102.7 mph at the 1/8th in 7 seconds flat.

[Sardonicus]

db484bhpv8 said:

With a 3.08:1 diff and 265/35/18 tyres mine runs a shade over 30 mph/1000 revs in 5th. Atr 3000 rpm i see 91 on the Tomtom. So 175 should be had if i am near to 5800 rpm in 5th.

Before anyone questions the acceleration being affected.
I ran a 10.8/129 1/4 mile last weekend. I was at 102.7 mph at the 1/8th in 7 seconds flat.

Too many people get hung up on low diff ratio's IMO its always been the same, you are proof Derek especially seeing you do 1/4 mile sprints regular back in the day times you heard cars screaming their tits off over the finish line because they run out of gearing more so with slush boxes

[fatboychim]

db484bhpv8 said:

to add.. i have Aerocatches fitted to my bonnet so thats not an issue.

The splitter is something worth considering

For what I costs if you use the guttering method shown in Peters photo its probably worth doing, although if you were happy at 158 I doubt another 10/15mph will make much difference.
My understanding is that it's actually a spoiler in that it disrupts the air following up the curved surface behind the radiator.
A splitter, I believe, protrudes in front of the car and divides the air above and below with the aim of creating downforce, unless it's on a Corsa in which case none of this matters as long as it's big.

[QBee]

Sorry, off thread, but that Corsa spoiler description has me giggling.
Cadwell Park, yesterday, slowest car on track (but could not fault his track manners) was a Ford Puma. The owner clearly had a great sense of humour. Absolute shed of a car, covered in mouse-coloured fur, bits missing here and there, "m&m" in black on the bonnet, and a seriously large spoiler on the rear, touring car sized!!
I doubt he broke 70 mph all day, but made us laugh.


Back to business. Yes, it's a spoiler, or gurney, not a splitter, but it works. It disturbs the airflow underneath the car, thus creating a little bit of a vacuum. Not as much as between a Tory politician's ears, but enough to pull more air through the radiator, pull the car down onto the track a little, and suck the bonnet down.

I agree with you about Federal RSRs. Amazing grip when cold, and a surprsingly good track tyre. Takes less than a mile on track to be up to operating temperature.

[SILICONEKID345HP]

db484bhpv8 said:

With a 3.08:1 diff and 265/35/18 tyres mine runs a shade over 30 mph/1000 revs in 5th. Atr 3000 rpm i see 91 on the Tomtom. So 175 should be had if i am near to 5800 rpm in 5th.

Before anyone questions the acceleration being affected.
I ran a 10.8/129 1/4 mile last weekend. I was at 102.7 mph at the 1/8th in 7 seconds flat.

What about 0 to 60 times and does it effect the rapid pick up ?

Been trying to find the correct crown wheel and pinion but it is a minefield . CTS want over 1k to supply and fit one then there is the cost of removing refitting and postage .

Where can i get one cheaper? even if i buy one from Australia its going to cost a small fortune with import duties ..

Anyone understand this

"TVR chimaera are not used in australia but from what i recall from previous customers is that you have a 0578 (7.75") gearset so on the side of the crown wheel of your gearset starts with 0578.
The Gear sets advertised here are 0575 7.5" gears they will fit the 0578 geared diff but with the use of a 0.075" spacer used in conjuction with the original pinion depth shim to space it out.
We do not have any good used 0578 3.08 gears.
we do keep new 0578 3.08 gears listed in our ebay store under item eBay item number:151384173836
The part number for the used gears was a GMH part number which probably means little to you 92140213"

http://www.ebay.co.uk/itm/151384173836?ru=http%3A%...

Edited by SILICONEKID345HP on Tuesday 2nd September 19:31