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Mph Vs Rwkw List


JP300

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Some guys have more power than they think and some have less. A good comparison.

I would say most people aint guessing what power they "think" they have.

They would be quoting the power figure from the dyno sheet their tuner handed them after the car was tuned.

It all comes back to the old dyno argument!

It would also depend how the car launched wouldn't it? Should the 60' time be included too?

Surely if you can make .3 of a second on the launch, it would give you an extra few mph at the end.

That would be why the auto's are quicker for the same or less rwkw figure?

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It would also depend how the car launched wouldn't it? Should the 60' time be included too?

Surely if you can make .3 of a second on the launch, it would give you an extra few mph at the end.

That would be why the auto's are quicker for the same or less rwkw figure?

Rob, in my limited drag experience I'm finding that a quicker 60' (say 0.1 better) and faster ET has marginally dropped rather than increased my mph by 1 to 2 mph in my auto.

It's a bit harder to get your head to understand it, and it seems to defy logic, so I'm going to try to work this out mathematically to see if I can prove it.

I think it's because if you have a good (or better) half track mph you'll complete the second half track more quickly, and have insifficient time to reach the mph that your accelerative capability could provide.

I have an applied maths background, so I tend to looks at numbers a bit differently.

I have a spreadsheet that where I have another rough way of comparing power, and that is by the average rate of acceleration of the car in the second half of the track, which takes into account half tack and full track speed, and the time taken to complete it. Of course gear shift times may infleunce results.

That leads to the other issue of peak power versus sustained power. Some people may have a good peak power level, but it drops off sharply (all over quickly). If you sustain the power/torque over a wider rpm you will have a good rate of acceleration. In the manual if you change to 4th in the second half track your average acceleration will be disadvantaged compered with a manual. In my 1st run in my manual F6 I believe I ran the entire 2nd half in 4th gear and picked up 47mph. My manual car is set is set up for sustained power up to around 7200 revs, so that gives you a different perspective on the matter.

I'm still new to all this, so I welcome comments from more experienced guys.

Brian

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yeh there could be a bit in that, I don't know,

my mph lifted a bit on my quickest 60ft,but it had droped to about 26 degrees by then. so I put it down to ; most times the quickest 60ft is the one that you got the best traction on. which most times you done the biggest burnout in so you got a bit more heat soak. or you let your tyres down a bit more (which does rob a bit of mph)

imo

David

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Any Dynowog tunes here.

Yes, one of mine - the 311rwkw & 115mph on MT's. That tune also ran ~315 and 116/117mph on a different day with streets.

Both Wog tune and Extreme tunes were VERY similar (identical) mph Vs dyno readout.

Tyres play a big part and should be listed along with Trans if you want true comparrisons.

Street tyres always add mph above MT's or slicks, this is common knowledge.

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Rob, in my limited drag experience I'm finding that a quicker 60' (say 0.1 better) and faster ET has marginally dropped rather than increased my mph by 1 to 2 mph in my auto.

It's a bit harder to get your head to understand it, and it seems to defy logic, so I'm going to try to work this out mathematically to see if I can prove it.

I think it's because if you have a good (or better) half track mph you'll complete the second half track more quickly, and have insifficient time to reach the mph that your accelerative capability could provide.

I have an applied maths background, so I tend to looks at numbers a bit differently.

I have a spreadsheet that where I have another rough way of comparing power, and that is by the average rate of acceleration of the car in the second half of the track, which takes into account half tack and full track speed, and the time taken to complete it. Of course gear shift times may infleunce results.

That leads to the other issue of peak power versus sustained power. Some people may have a good peak power level, but it drops off sharply (all over quickly). If you sustain the power/torque over a wider rpm you will have a good rate of acceleration. In the manual if you change to 4th in the second half track your average acceleration will be disadvantaged compered with a manual. In my 1st run in my manual F6 I believe I ran the entire 2nd half in 4th gear and picked up 47mph. My manual car is set is set up for sustained power up to around 7200 revs, so that gives you a different perspective on the matter.

I'm still new to all this, so I welcome comments from more experienced guys.

Brian

Brian, I alluded to this a couple of years ago, I summed it up as average power accross the rpm range..

It's all well and good having 300rwkw, but when it's late in the revs and drops off in 200rpm, it's not much good to you.

Every car that has posted a very good ET makes bulk power (Torque actually) early to get the weight moving and (as you say) Sustains that power to charge down the mph in the top half.

Boost = Torque. Get boost in as early as possible and your 60' & ET will benefit. Hold that power till the upper rpm limits and you have a good mph to reflect the power..

Further to this, as we discussed a while ago; your car wasn't that much quicker than mine to cover the second half of the track, even though it made nearly twice as much power..

Manuals probably suffer from ( this is my theory) time in each gear. Not shift time, not boost dropping off, not having less boost off the line, none of that!!

I managed a 1.61 60' in a manual with a stock clutch, don't give me the no boost off the line bolony arguement!

We not only have to manually shift (which isn't much slower than the A4) but we have to also shift once more (big hp guys twice) than the autos. Also time spent in the torque band is less. We move around the revs quickly and the car has less time to accelerate with each given amount of power at any particular rpm point (make sense) First gear is over in a blink, then we hit 2nd. Auto uses the available power for longer.. I drove around this issue and that's how I got good ET's from my power. Shift early, spend more time with the engine making power for the given gear. Shifting earlier also makes the engine load up, hence make boost quicker, hence make torque earlier - hence accelerate quicker.

Are we off topic enough??

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It's all good feedback and yes we have strayed a bit away from the topic but some interesting thoughts on the comparisons between similarly listed powered cars.

Some of them are pretty close to each other when you start looking at comparing the MPH, RWKW and same transmission cars.

Keep the figures coming in guys !! I will plot them all in one graph and then in separate graphs based on transmission over the weekend.

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We need more cars ... Anyone else have some figures to throw in?

BF 6 speed auto 358 rwklw and 11.2 125mph

Ba 4 speed 360 rwklw 10.8@122 mph

Ba 4 speed 284 rwklw 11.6@117mph

Ba 6 speed manual 358rwklw 11.8@122mph

CV PERFORMANCE

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