Technical 0-60

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Technical 0-60

The_D

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So here I am wanting to know how to drag the best 0-60 time out of my little W-reg, bog standard Seicento Sporting. But here's the catch -- I want to do it by technique alone ;)

So when exactly do I change up? I don't want to be red-lining it all the time, because I know that's not the optimum. Anyway, I've been looking into power and torque and I'm a bit confused >.<

Do I just change up where the engine hits the revs that give peak torque, before it falls off? (That'd be 3250 rpm)

If this is the case, why do they quote the max power (54bhp at 5500 rpm)?

Any help much appreciated :)
 
depends on the engine.. I've not got a stock 1108 to test but you want to change up when acceleration in the gear you are in is the same as the gear you're chaining into or you run out of rpm. For my 75 engine with peek power at 6200rpm and the limiter at 6500 I run out of rpm first, on the D5 change point is about 4600rpm (5000rpm red line) as torque and power is dropping like a stone by then.
 
The_D said:
So here I am wanting to know how to drag the best 0-60 time out of my little W-reg, bog standard Seicento Sporting. But here's the catch -- I want to do it by technique alone ;)

So when exactly do I change up? I don't want to be red-lining it all the time, because I know that's not the optimum. Anyway, I've been looking into power and torque and I'm a bit confused >.<

Do I just change up where the engine hits the revs that give peak torque, before it falls off? (That'd be 3250 rpm)

If this is the case, why do they quote the max power (54bhp at 5500 rpm)?

Any help much appreciated :)

Change at 5500 is best.... ish. Why Because. Well is like this. If you have a large gap between gears then there may not be enough power and torque to continue the acceleration in the higher gear, whereas if you had hung onto the lower gear for another 500 rpm then the higher gear may be better then.

Experimentation time.

Cheers

D
 
Surly there's still useful power being developed, thus acceleration, beyond 5500rpm? How much further would be the question.
 
StoneNewt said:
Surly there's still useful power being developed, thus acceleration, beyond 5500rpm? How much further would be the question.

Yes, but no, the reducing torque curve at this point means that the amount of acceleration is reducing. Yes the engine is turning faster therefore the car must be going faster, but if changing gear and getting more torque from the lower revs the acceleration will be better.

If, however the gap between the gears is too big, then changing may drop the engine out of the power band, so it may be worth hanging onto the lower gear for a bit longer.

Cheers

D
 
I've been playing with this, and in the lower gears up to 3rd 5k is he best change, then for 4th and 5th 5.5K seems to bring you around the peek torque better than 5K
 
rallycinq said:
Yes, but no, the reducing torque curve at this point means that the amount of acceleration is reducing. Yes the engine is turning faster therefore the car must be going faster, but if changing gear and getting more torque from the lower revs the acceleration will be better.
Wouldn't the ideal solution be plot a thrust v's road speed graph from each gear and see where the thrust overlaps? I've always found that to be somewhere beyond peek power.
 
k sounds like a bloody good plan i gotta start learning the technique for launchin my bog standard cinq... Torque and horsepower are 2 completely seperate things... torque is a measure of turning force. this, when refered to on engines, is what you will feel as acceleration. now horsepower is a measure of "power" usually ull see it as BHP brake horse power this is measured on a dyno the car is run to its peak speed and a brake is applied to the rollers whatever braking force is needed to drop the revs is the engines BHP figure *i understand thats the way it works:confused: * u wanna be launching it just below the point where the most torque is produced so it doesnt spin up lowering your tyre pressures will aid this and keep it floored till 500-1000 over that point then change the revs should end up around the point u initially launched it from keep going thru the gears keep it floored to about 2000 over in 4th cos 5th is a very long gear well it is on the cinqs any way hope this helps...


Stain
 
Launching is a complete art TBH, it takes a bit of control on the clutch and accelerator to prevent spinning up on bogging down under power, but when you get that feel for it it's easy.
 
doing a hand brake start will knock some some time off
and if done right is better for your car as all the slack
in the drive train is taken up gently. So have the hand-brake
on bring clutch up so the car moves slightly bring the revs
up to 4k then simultaneously drop hand-brake, lift off the
clutch sharply and floor the accelerator. it takes a bit
of practise but is quite easy(y)
 
The limiting factor after that becomes wheelspin. The point at which the tyres are giving their most grip is immediately before they start to spin. You can loose more time on the overall 0-60 time with excessive wheel spin, than taking a more measured approach and get the car rolling a bit before giving it the full moo.

Cheers

D
 
sei tan said:
doing a hand brake start will knock some some time off
and if done right is better for your car as all the slack
in the drive train is taken up gently. So have the hand-brake
on bring clutch up so the car moves slightly bring the revs
up to 4k then simultaneously drop hand-brake, lift off the
clutch sharply and floor the accelerator. it takes a bit
of practise but is quite easy(y)


This technique is for turbo engines.
It's to get the boost up to avoid turbo lag.
 
sei tan said:
doing a hand brake start will knock some some time off
and if done right is better for your car as all the slack
in the drive train is taken up gently. So have the hand-brake
on bring clutch up so the car moves slightly bring the revs
up to 4k then simultaneously drop hand-brake, lift off the
clutch sharply and floor the accelerator. it takes a bit
of practise but is quite easy(y)

Doesn't sound to different from what you are supposed to do, other than the 4K revs.

Cheers

D
 
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