RPM's and SHIFTING
06-05-2007, 09:27 AM
#21
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Originally Posted by OuterHeaven
Well basically if you are drag racing then I would suggest shifting pretty much at rev limit (around 6300 to 6400 RPM). Yes peak power is lower than this but the average power put to the ground will be bigger. This is how race cars setup their gear ratios. Basically you want to stay around the peak of the peak HP "hill" as much as you can (look at any stock dyno graph and you will see what I mean). This means you want to be on both sides of the peak HP "hill" so therefore you should shift after peak power is made. Now if you are just doing a little aggressive driving then do not worry about the tach but just focus on the feel and what is in front of you.
06-05-2007, 09:36 AM
#22
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Have you actually looked up our gear ratios and looked at our dyno graph?? We really do not lose all that much power after peak not until basically rev limit. The hardest part about shifting correctly usually means you are past peak torque and the butt dyno no longer feels the "same" when really you are actually accelerating faster. The truth about our cars is that shifting pretty much at redline is ideal in most gears except from 2nd to 3rd you really want to shift right before rev limit.
06-05-2007, 01:50 PM
#23
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Originally Posted by OuterHeaven
Have you actually looked up our gear ratios and looked at our dyno graph?? We really do not lose all that much power after peak not until basically rev limit. The hardest part about shifting correctly usually means you are past peak torque and the butt dyno no longer feels the "same" when really you are actually accelerating faster. The truth about our cars is that shifting pretty much at redline is ideal in most gears except from 2nd to 3rd you really want to shift right before rev limit.
why would you wana shift on the downward spiral of the hp/tq curves.. by the time your cutch catches up with the motor revs your still going to be past optimal peak power and not before it to take advantage of it... its pointless to take it to a place were power is not made and your loosing power and momentum...
06-05-2007, 06:49 PM
#24
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The point is to put down the most power (HP) to the ground. If you know anything about calculus it is all about the area under the curve... So basically when you shift right at peak power you move far down the power band. You will have X amount of average power being put down but if you shift after peak power is made you will not fall down as far in the power band after you shift and therefore make Y average power which will be higher. Like I said it is all about the area under the curve. This is a very basic principle to go fast. Also just because you past peak power does not mean you are not accelerating and you are definitely NOT losing momentum (you would only loose that if you lost speed and therefore would actually be going down the rpm's).
06-05-2007, 06:57 PM
#25
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from peak to end the rpm shift is to small to get anything out of before hitting the drop of power...if you shift so you go below peak you will have a longer degree of peak power within the rpm range..if you go to the redline all you are doing is going in and out of peak in greater intervals of time then you would be shifting a tad earlier which will alow you to hit peak and stay in peak a longer interval of time... hense putting you ahead of your competitor... race anyone or go to the track and try it out.. you will see you should get better times taking it a few rpms shorter then going all the wat to the redline..
06-05-2007, 07:56 PM
#27
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Originally Posted by OuterHeaven
Unfortunately I am boosted and it is hard not to hit the limiter in the first couple gears... Damn traction. I have no time for the actual track right now but I will try some gtech runs.
if your on boost then you do not experience that effect captain obvious.... your opinion would be now sorta irelivant(sp).. these kinds of driving situations would apply to people who are N/A.. and not on boost..
06-05-2007, 08:23 PM
#28
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i wonder if this is why my car feels kinda boggish going into 3rd gear ? ive raced a couple of people and i ussually take redline first and second and going into third it bogs and then picks up some. what can i change and what are people launching at ? i have 18s with fuzion zris annd feathering the clutch and at 3k its too high and too much wheel spin
06-05-2007, 08:47 PM
#29
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how fast are you engaging your clutch and what rpm are you shifting at and what rpm is it catching at.. you shouldnt be bogging unless your engaging kinda low in the true power band of the car (3700rpms is were it starts)
06-05-2007, 10:35 PM
#30
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engage pretty quick at 6k and it drops to above 4.5 i belive and do it again into 3rd and rpms drop lower it seems like and it takes longer to end the gear. i knmow the gear is longer an all but it seems slow in third
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