If you have the gear ratio exactly matched to the peak power vs aerodynamic drag equilibrium point, then you will be able to get to the maximum speed of the given car. This is rarely the case because you have to calculate it and then change things to make it happen. Plus making this happen is not useful for a road car as all of the ratios needed to get it to the top speed will make it a pig to drive normally.

So if your peak power is at 6500 rpm then you work out from that what the equivalent speed is to have equilibrium from aerodynamic drag (yes plus rolling friction etc, but we'll keep it simple because the aero drag is the limiting case eh?). In other words the work being done by the engine is exactly the same as the work required to push through the air at that speed.

Now we make the overall gear ratio in the top have the engine running at exactly 6500 rpm. Drive the car to find out the top speed. Use something other than the speedo to measure it, because the speedo will be wrong.

Obviously for a given torque, more revs equals more power, equals higher top speed. But (echo from Matt ) HORSES FOR COURSES. Shifting the torque band up the rev range by changing cams, heads etc will also increase peak power and for a given Cd and frontal area, will thus increase the top speed.

Someone go and do the experiment and report back on your results.

cheers
michael

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the world is a book, and those who do not travel read only a page
66 Mini Minor sponsored by http://www.lifeonthehedge.com.au/ The Dog Harness Specialists
It was a pleasure ausmini. I'll miss all you misfits and reprobates

Thought Farina was 'fine flour' in Italian - what has that got to do with a car?

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David L


My greatest fear in life is that when I die my wife will sell my Mini and tools for the price I told her I paid for them!

it's the guys name...

Farina (as in Pininfarina) is an Italian design house, they have designed (and sometimes made the bodies of) countless makes over the years including some Fiat, Lancia, Maserati, Ferrari, Alfa Romeo, and various UK cars including said A40 Farina (which is mostly a Morris Minor 1000 mechanically).
It was one of the world's first `hatchbacks'.
see also http://en.wikipedia.org/wiki/Pininfarina

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

I am having a seniors moment here. There were a few Italian design houses at that time and later. I know Bertone and Ghia but who were the others ????

Mike

Bertone. Pininfarina, Vignale, Ghia, Zagato, Frua, Carrozzeria Touring etc

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Lucy - 64 cooper s replica
Lulu - 66 deluxe

How about Italdesign - you know the one run by the master Giorgetto Giugiaro - responsible for the likes of the Iso Grifo




funny how no-one wants to associate the Italdesign company with this gem

_________________
the world is a book, and those who do not travel read only a page
66 Mini Minor sponsored by http://www.lifeonthehedge.com.au/ The Dog Harness Specialists
It was a pleasure ausmini. I'll miss all you misfits and reprobates

The reason is that while Italdesign was hired to do a facelift on the Marina their design was knocked back and the facelift was done by one of the Leyland in-house stylists. The marketing department knew of the association of Italdesign in the facelift process and changed the name of the car from Morris Marina to Morris Ital even though there was no Ital in the design.

The Marina was actually a huge success. It was a fairly simple car to make with a high profit margin and they made thousands of them.

That's not relevant. If we're talking indicated 60mph, then we're talking implied 104mph. If he had my current speedo, indicating 60mph, he'd have sirens and lights after him... We can't be held responsible for the quality of the information we're given - if the input data's wrong, then it's not our fault the output's wrong. Same deal as computers get!

But this is Hanra - he's probably spent $2k on his tacho, calibrated it to 0.00001Hz, and there's probably 48207 photos of it on here.
No offense intended Hanra.