Puff The Magic Wagon!

iTrader: (2)

Bajie

Electronic Rev Counter may not be accurate either!!

Just for interest, those lovely slicks we get from Stef with a lower rolling radius to standard mean that we actually go slower for the same revs than usual! So when we say in 2 weeks time "I was doing 120 coming into paddock" - we probably weren't by a factor of slick + speedo inaccuracy.

Anyone got a speed trap? or Laser eh? Stuart H?

Bajie

Now I'm really upset!
I think this is going to be one of those "unanswereable" questions.
But ok.
Lets say the rev counter is inaccurate.
Why then, can I get to the redline in every gear but fifth.
I have a friend who's Supra gets to 175 very, very quickly but then, to get to 185 takes a millenium [and a lot of autobahn].
To overcome this will mean more tuning to give it the power to break through.
But the other scoobies are making it past 6000rpm and also to the limiter.
I know some of the Supra guys take their spoilers off to make high speed gains but don't think this is the issue with mine yet.
Though its not something I would do given the choice.

Bajie

Does anyone out there know if our cars have a 155mph speed limiter?
6000rpm [redlined at 7k] doing 155mph [clock speed], lots of room to go before the pedal hits the floor. But it aint going any faster!
Is this the aerodynamic wall being hit?
I'm running with a PPP.
I know the speedo is not the most accurate thing in the world, but I do believe my rev counter.
Has anyone out there managed to get 160?
Or even 157.
I know a WRX which hits 150, but then he has hit the rev limiter.
Any ideas?

ex-webby

This thread has been moved to general on request from Bajie.

Julian Rowland

I have got 159 mph on a UK car my99

Try harder!

Bajie

Julian

What rpm?

Stuart H

Julian,

That best not have been on the public road!

Bajie,

The European Union passed legislation in the early part of 1997 which allows them to limit the top speed of cars. Many new cars are already fitted with limiters, but the limiters are set to something like 160mph. The system is basically the same as cruise control (if you have that chances are you've got a limiter as the technology is the same). As soon as the law is passed requiring cars to be limited, you will just have to take the car into your dealer for him to twiddle the limiter, and there you go. Your car is restricted to the set speed.

And what speed do the wonderful EU want these things set at? <B>62mph</B>.

Marvellous ain't it.

NITO

You beat me julian,

I had 158mph at approx 6,300rpm when my scoob was standard before a lorry pulled out in front up ahead, I was overtaking a Porsche in Italy at the time (should have seen his face when he was overtaken by a Subaru Estate! I don't think he'd ever even heard of Subaru)I think he would have been on his limiter as he was certainly going for it.

I remember thinking at the time, if the Subaru according to magazines pulls around 24mph per thousand rpm in top gear, and I still had 700rpm left at nearly 160, then theoretically the gearing of a uk scoob should allow it to get to around 180mph provided the car was powerful enough to acheive this (400bhp+at least I would have thought).

To answer your question, no the scoob isn't limited to 155mph, except standard jap imports which are limited to 112!

HTH
Nito

SCOOP

According to my Blitz multi turbo timer, which is certainly calibrated correctly (ie kmh to mph )the car has managed 269 kilometers per hour and is off the speedo. This converts to over 160mph, seems unlikely to me, because I would'nt think the gearing would allow it, but it looks good.

Done a few things to it (MY 97 5door)
No cat, Magnex backbox, Induction, Flywheel lightened to 8 1/2 Kg, plus a few other minor mods.

Will regularily produce 0-60 in 4.9 secs, but seems to destroy clutches pretty quickly.

Does anyone know how accurate multi turbo timers are when it comes to recording top speeds.... and is the gearing capable of producing in excess of 160mph, seems doubtful to me ???

SCOOP

Puff The Magic Wagon!

iTrader: (2)

Speedo Accuracy gents?

PTMW! @ Revs shootout did true 134mph @ indicated 145mph

(Stuart H - on an MOD airfield )

[This message has been edited by Puff The Magic Wagon! (edited 16 October 2000).]

Bajie

Puff.
I did say it was an indicated speed and I believe my rev counter more readily.
I have heard many times the speedo can be +/- 12mph accurate.
Also the car did not exceed 1.1 bar.
My problem being my car has never gone over 6000rpm in fifth.
Maybe I should have asked for the highest rpm in fifth gear.

NITO

Of course you're absolutely right puff which is why it's better to do it looking at revs. Any idea what the revs were at the the indicated 145mph. My car has a slightly bigger rolling radius 616mm as opposed to 612mm which should make the speedo under read if anything making it slightly more accurate at the top end than stock. So ner nernernerner Julian, perhaps I beat you after all!!

It would be interesting to rig up the proper equipment and do some high speed runs comparing revs (not the magazine!) to true speeds! Perhaps an idea for a forthcoming sidc/true grip feature........

Nito

Julian Rowland

My speed was achieved at Bruntingthorpe, not the public roads (Iam not that brave with my licence). I am not sure of the RPM but it was way below the max. The car was still pulling but the corner was looming. If someone wants to donate Ap's I will be able to brake later and hit 160mph!

Diablo

Bajie,

The answer to your question is simple.

Its air resistance.

To get over 6000 in 5th you'll need more power or less drag (basically)

Thats why a Macca F1 (the road car) was faster over 150 than a Macca F1 race car.

Hope this answers your question!

Cheers
D

NickM

Bajie,

You say the car accelerates up to 155mph quite quickly and then refuses to go any faster. This sounds like something other than aerodynamics although at these speeds it's going to be a *major* contributor. The weight of the car will play a big part as well, if you took out all those reggae CD's you'd be looking at at least another 7mph

Stuart H - Speed limited to 62mph? The *******s will have to catch me first.

spence

You could always refuse to drive with me as well... that would save a fair bit on weight...

Bajie

Well the car has the Prodrive Exterior Package which should make it a bit more slippery than the standard cars which are getting over 6k.
So weight could be the problem.
I'll take some of the more bass heavy tunes out and try again tonight.

Bajie

Spence
I'd save on weight, but lose on street cred.

Moss

I have at best achieved 146mph, recorded on GPS in MY99. Speedo is 10-12% out and this equates to 162mph. Even the GPS isn't dead on, but it seems better than speedo.

Moss

AlexM

Hi,

Actually, weight doesn't have anything to do with top speed (assuming your tyres are correctly inflated for the load).

Aerodynamic drag is the limiting factor for top speed. If your car is full of subwoofers, reggae CD's, or fat blokes it will be faster because the ride height will be LOWER, hence less drag and higher top speed . Not so good for acceleration though.

Cheers,

Alex

edit - actually loads of ICE will make the car slower due to increased load on the alternator. Close the windows, turn off all electrical gizmos including A/C for top speed!.

[This message has been edited by AlexM (edited 16 October 2000).]

Bajie

Stereo was off, just got a new downpipe and centre section.
Fan was on 1 but not using AC.