Safe Speed Forums

Redline all the way!! (and its a gpz5 so it just begs for more! )

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Science won over religion when they started installing lightning rods on churches.

4 cylinder
1100cc
8900 rpm max
100 bhp @ 7500 rpm
77.3 lb/ft torque
0-60 3.1 seconds
Max speed 147 mph
Electro-hydraulic servo-assisted abs.
BMW.

256 KW @ 7900 rpm
365 Nm @ 4900 rpm
1542 kg (fat b*stard... needs to go on a diet)
max speed (unlimited) 280+km/h
0 - 160km/h 11.6s

Can we have an English translation, please?

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"Show me someone who says that they have never exceeded a speed limit, and I'll show you a liar, or a menace." (Austin Williams - Director, Transport Research Group)

Any views expressed in this post are personal opinions and may not represent the views of Safe Speed

sure

256 KW @ 7900 rpm = way more than anyone could possibly need
365 Nm @ 4900 rpm = way more than anyone could possibly need
1542 kg = far too much
max speed (unlimited) 280+km/h = you must be joking, who would want to travel that fast?
0 - 160km/h 11.6s = I think I wet myself.

A small point, but why would anyone think that limiting cars to 101 mph will reduce CO2 emmisions. I would draw everyones attention to the Hummer H3 which has the smaller 3.5 litre engine, max speed 100mph mpg 16 (yeah right probably nearer 10). Then there's the Fiat Panda, oh can't count that, it maxes out at 105mph.

If you want to reduce CO2 then reduce CO2! This idea is just barking mad!

Actually he has deliberately confused matters by using Nm instead of lb/ft. Car A is a N/A Mondeo sized petrol (147lb/ft). Car B is a small diesel with rather a low power output (236lb/ft).

Since power is a function of torque and revs (torque * RPM * 1/5250 = hp) car B would have a very narrow torque band (exactly the opposite of what Mpaton says he wants). Some kind of CVT transmission would be required to keep it within it's power band, either that or a HGV style gearbox in which case you couldn't perform the 18 or so gearchanges required to get to 60 within 6 seconds.
Anyway, acceleration requires a good power to weight ratio as well as gearing which car B just doesn't have. In fact both have the same power to weight ratio at about 72bhp/tonne. Car A has the wider torque band as demonstrated by it's higher power output car B is reminiscent of an 80's turbo diesel, blink and you miss it blip of power.

This page may help mpaton understand the physics behind it little more.

18 gearchanges at a nice quick 0.3 seconds each would take 5.4 seconds.

So we would have 0.6 seconds of drive left for the 0-60 acceleration.

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Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety

I'm trying to imagine the sounds....

My C3 has an alleged top speed of 110mph. I think I had it up to 103 once. Can't have that then. Anyone know of a car which can't do >101mph?

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Andrew.

my old Alfasud. The short ratio box limited it to 100mph.
Likewise the old mkII escort topped out at about the same speed due to its 4 speed gearbox.
Both got to 100 easily though so I'm sure they could have gone faster with different gearing.

Almost right, but car B will accelerate quicker. How do I know? We used to own both

Car A was a Vauxhall Vectra
Car B was a very heavily modified VW Lupo Sport TDi, that went like shit off a shovel.

Obviously there's vast difference in the practicality of the two, but I believe Skoda make the Fabia Estate using the VAG 1.4 PD TDi which returns 60+ on the combined, is already in emissions band B, and is a Very Useful Vehicle which you can buy today for next to nothing.

We need more cars like that and less tat like Humvees or Range Rover Sports.

"Very useful vehicle" - you sound like my Dad.

You may have a different perception to me as to what constitutes a fast car.

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Malcolm W.
The views expressed in this post are personal opinions and do not represent the views of Safespeed.

what sort of Vauxhall Vectra weighs 1800kg????

Acceleration wise, it saw off most hot hatches, most sporty exec types from 0-60 in a cloud of diesel particulates. Obviously the top speed was hopeless, but who gives a shit?

Someone is talking out of their backside........

62mph = 27.7m/s
80bhp = 80 * 746 = 59.7kW

Ekinetic = 1/2*M*V*V = 0.5 * 1100 * 27.7 * 27.7 = 422kJ

Einput = WT = 59.6k * 6 = 358kJ

So somehow your car B is 118% efficient - and that that excludes: the time for gear changes, negative effects of drag, the necessary clutch slip and transmission loss

Methinks your figures are the only heavily modified thing about your car B


edit, your car A works out to be 75%, which is probably about right.

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Views expressed are personal opinions and are not necessarily shared by the Safe Speed campaign

Sorry, I posted the standard power output of the 1.4 VAG motor. We got ours done by a company called JabbaSport who specialise in VAG tuning.

I've got a video which I'll post up so you can see what I mean

I guess you also quoted the standard MPG, speed and weight huh?

Mine - with me in it!

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Pecunia Prius Equitas et Salus

What's that in real money? As in mph?

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Pecunia Prius Equitas et Salus