Gear ratios...
#167
Nordschleife Master
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It's better than stock, but still far from optimized.
#168
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I really like the idea of using a 2.7 transmission....you would still upgrade 3-5/6 and LSD. In case you have a failure you have your OEM GT4 transmission stock which still has warranty.
#171
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#172
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This all fits the subjective perception many of us have that 2nd and 3rd are too long (arguably, 1st also).
Last edited by Manifold; 12-08-2016 at 10:05 PM.
#173
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Bill, Great chart. I had seen one of these (yours?) on a different board. It would really be helpful to the discussion if you could play back the difference between GT4 stock and GT4 with 2.7 transmission. The ratios are in post #123, left column.
Also, I assume the sheet plots v(t) as well. That would be interesting, too!
Thanks so much!
Also, I assume the sheet plots v(t) as well. That would be interesting, too!
Thanks so much!
#174
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Hi Bill, been reading your posts on Pelican for probably 15 years. What would be nice is another chart that shows the difference vs. speed and third chart showing the integral of that difference chart vs. speed.
#175
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Cool! Acceleration vs speed is enlightening but I think power vs speed is easier to see the overlap differences. The intersections of the acceleration vs speed and power vs speed curves are of course the same (if you take into account aero power consumption).
#176
#178
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Looking at the excellent graph, I would have thought a lower final drive would be a good move for the GT4. It's a lot simpler to replace the crown and pinion than strip down a gearbox and should be a lot cheaper in labour though obviously the gears will be expensive. Hopefully someone will make some parts in the next year or two.
My 996.1 GT3 (never sold in the US) has a cup car FD in it and it's a rocket ship and you have a good time changing gears a bit. It's like adding 30-40 BHP. BTW that car also runs an aluminium flywheel and small diameter twin plate race clutch which enables the engine to accelerate RPM quicker.....and I raised the rev limiter to 8500 (which is just an on/off software switch 7800/8500 on that model).
My 996.1 GT3 (never sold in the US) has a cup car FD in it and it's a rocket ship and you have a good time changing gears a bit. It's like adding 30-40 BHP. BTW that car also runs an aluminium flywheel and small diameter twin plate race clutch which enables the engine to accelerate RPM quicker.....and I raised the rev limiter to 8500 (which is just an on/off software switch 7800/8500 on that model).
#179
Nordschleife Master
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Looking at the excellent graph, I would have thought a lower final drive would be a good move for the GT4. It's a lot simpler to replace the crown and pinion than strip down a gearbox and should be a lot cheaper in labour though obviously the gears will be expensive. Hopefully someone will make some parts in the next year or two.
My 996.1 GT3 (never sold in the US) has a cup car FD in it and it's a rocket ship and you have a good time changing gears a bit. It's like adding 30-40 BHP. BTW that car also runs an aluminium flywheel and small diameter twin plate race clutch which enables the engine to accelerate RPM quicker.....and I raised the rev limiter to 8500 (which is just an on/off software switch 7800/8500 on that model).
My 996.1 GT3 (never sold in the US) has a cup car FD in it and it's a rocket ship and you have a good time changing gears a bit. It's like adding 30-40 BHP. BTW that car also runs an aluminium flywheel and small diameter twin plate race clutch which enables the engine to accelerate RPM quicker.....and I raised the rev limiter to 8500 (which is just an on/off software switch 7800/8500 on that model).
#180
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Hello all,
Matt was kind enough to send this my way for review, and it is great info. I wonder if the max rpm should not be lifted to 7800 rpm (I know they're street cars, but I do extend to redline from time to time, and it is instructive to see the true max speed in gears).
But, herewith for further discussion:
Matt was kind enough to send this my way for review, and it is great info. I wonder if the max rpm should not be lifted to 7800 rpm (I know they're street cars, but I do extend to redline from time to time, and it is instructive to see the true max speed in gears).
But, herewith for further discussion:
Last edited by stout; 12-09-2016 at 05:49 PM.