third gear on 951's
#1
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third gear on 951's
Something today got me kind of worried about my car. I was merging onto the interstate and decided i would rip it through third to red line. Ive only had the car for about three weeks now and i think this is the first time i took it all the way through third and the thing that got me worried is that the speedo reads right under 100 when ive maxed out third. Correct me if im wrong but i thought third gear in 951's went up to 110. I know speedometers are pretty inaccurate at high speed but i dont think there should be that large of an error margin at that speed. I did it two more times and it read roughly the same speed right under 100 both times. Any insight into this is appreciated.
#3
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With the stock tire diameter (24.7 inches), the speedometer is calibrated to read just about 100 mph in third gear at 6400 rpm. However, in practice, real tire diameters do not match the theoretical stock value. I'm running the original stock tire size (245/45/16) in S-03's, but the measured diameter is 24.0 inches on the stock rims and my speedometer reads high by about 3% because of that (i.e. it's really 97 mph when it reads 100).
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#9
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Every time I hit 100 in 3rd, always reminds me of the late 80's movie Dream Machine with Corey Haim? The one where the rich lady gives him her husbands 911 turbo. He gets pulled over and tells himself " I can't believe it....100 in 3rd gear!!"
So when my little 951 does it, makes me realize our cars can hang with the same late 80's 911 Turbos
So when my little 951 does it, makes me realize our cars can hang with the same late 80's 911 Turbos
#11
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It is my understanding that our cars will do an actual speed of 98mph in 3rd gear. However the models that use the ABS sensors to drive the speedo will be quite accurate while the earlier models that have a speedo sender on the transaxle show almost 112 at the top of 3rd.
Ahmet
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#12
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Does any one have the MPH for all gears 1st - 5th ????
My speedo does not work so it would be nice to know what speeds I am hitting in each gear...... also please include RPM at the stated speed.
Thanks,
Paul
My speedo does not work so it would be nice to know what speeds I am hitting in each gear...... also please include RPM at the stated speed.
Thanks,
Paul
#13
There is a graph in the back of the owners manual... Mine doesn't work either! Checked it after a spirited drive and found I was going somewhat faster than I thought I was!!
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1st 40.4
2nd 68.7
3rd 101.0
4th 136.8
5th 170.6
That is with a 951 3.375 gearbox at 6500 rpm with the calculated diameter of 245/45-16 rear tires.
Paul, your username suggests you have a 968, but you are asking about 1st through 5th???
2nd 68.7
3rd 101.0
4th 136.8
5th 170.6
That is with a 951 3.375 gearbox at 6500 rpm with the calculated diameter of 245/45-16 rear tires.
Paul, your username suggests you have a 968, but you are asking about 1st through 5th???
#15
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So we do hit 101 in 3rd... What was all that talk about only doing 98ish in 3rd a few months ago? I ought to get an owners manual. BTW, thanks for the info.
Ahmet
Ahmet