3800 rpm at 70mph? is this normal?
09-21-2015
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Re: 3800 rpm at 70mph? is this normal?
yes, it's normal? Why?
09-22-2015
#5
Dr Krieger of Modification
Re: 3800 rpm at 70mph? is this normal?
If you're only at 3400 at 70mhp why would you need another gear? Power band is from 3500 up. And you still have all the way from 3400 to 6800 before you'll need another gear.
My modified em2 goes well past 100mph quite easily autoX'ing, but if you're stock and using her on the highway you probably won't go past 100mph easily anyway.
If there was a sixth gear then the fifth would be shorter and probably end around 100, then you would shift. ...but again why would you need this?
My modified em2 goes well past 100mph quite easily autoX'ing, but if you're stock and using her on the highway you probably won't go past 100mph easily anyway.
If there was a sixth gear then the fifth would be shorter and probably end around 100, then you would shift. ...but again why would you need this?
09-22-2015
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Re: 3800 rpm at 70mph? is this normal?
I just thought it seem to be rapped out like it was higher than normal.. it may just be the louder exhaust that was on there when i got it... It doesnt seem to affect the gas mileage or anything.
09-22-2015
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Rep Power: 338 Re: 3800 rpm at 70mph? is this normal?
yep, these engines are happy revvers 
09-22-2015
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Rep Power: 485 Re: 3800 rpm at 70mph? is this normal?
exhaust won't change RPM vs speed. Really, nothing will except changing gear ratios and/or overall tire diameter. Even so, the latter will change it negligibly.
I've noticed about 3000RPM at 60MPH in 5th in my ex, so it's about normal. If you swapped your transmission for one made for a dx/lx, you'd notice a lower RPM for a given speed when compared to the ex, but that's because the dx/lx models have been equipped with a transmission with longer gears. The ex was meant to be sportier, so they designed the transmission with gear ratios that will rise faster than that of its dx/lx counterparts.
If you were to take your car to full redline in 5th gear (that is, right at the rev limiter), you'd be going near or about 135mph, not that I know from personal experience or anything
Automatics are speed goverend to about 110mph
I've noticed about 3000RPM at 60MPH in 5th in my ex, so it's about normal. If you swapped your transmission for one made for a dx/lx, you'd notice a lower RPM for a given speed when compared to the ex, but that's because the dx/lx models have been equipped with a transmission with longer gears. The ex was meant to be sportier, so they designed the transmission with gear ratios that will rise faster than that of its dx/lx counterparts.
If you were to take your car to full redline in 5th gear (that is, right at the rev limiter), you'd be going near or about 135mph, not that I know from personal experience or anything
Automatics are speed goverend to about 110mph
09-22-2015
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09-22-2015
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If you think a good mechanic is expensive, try hiring a bad one
Re: 3800 rpm at 70mph? is this normal?
Speedometer needle position is strictly a function of engine RPM and gear ratios.
Speedometers used to be driven by mechanical means before they made it electronic and ran it through the ECM.
It's really only indicating how fast the ring gear in the differential is spinning (thus how fast the axles are rotating), not real vehicle speed.
The speedometer needle showing a speed number really has nothing to do with the actual speed of the car--- until the correct size tires are rolling on the ground, because the circumference of the correct size tire is part of the speedometer calibration. (5280 feet in a mile, measured tire circumference, #revolutions per mile.)
I can run a car in the air on a hoist with the speedometer showing 100+, but the actual speed is zero because it's not going anywhere..
Changing tire diameter only affects the accuracy of the speedometer (and odometer); actual road speed vs. indicated road speed.
GPS can verify that for you.
HTH
09-22-2015
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Rep Power: 485 Re: 3800 rpm at 70mph? is this normal?
You're right, I should have clarified. Changing overall tire diameter will change actual vs indicated speed
09-22-2015
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If you think a good mechanic is expensive, try hiring a bad one
09-25-2015
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Rep Power: 122 Re: 3800 rpm at 70mph? is this normal?
Right.
Speedometer needle position is strictly a function of engine RPM and gear ratios.
Speedometers used to be driven by mechanical means before they made it electronic and ran it through the ECM.
It's really only indicating how fast the ring gear in the differential is spinning (thus how fast the axles are rotating), not real vehicle speed.
The speedometer needle showing a speed number really has nothing to do with the actual speed of the car--- until the correct size tires are rolling on the ground, because the circumference of the correct size tire is part of the speedometer calibration. (5280 feet in a mile, measured tire circumference, #revolutions per mile.)
I can run a car in the air on a hoist with the speedometer showing 100+, but the actual speed is zero because it's not going anywhere..
Changing tire diameter only affects the accuracy of the speedometer (and odometer); actual road speed vs. indicated road speed.
GPS can verify that for you.
HTH
Speedometer needle position is strictly a function of engine RPM and gear ratios.
Speedometers used to be driven by mechanical means before they made it electronic and ran it through the ECM.
It's really only indicating how fast the ring gear in the differential is spinning (thus how fast the axles are rotating), not real vehicle speed.
The speedometer needle showing a speed number really has nothing to do with the actual speed of the car--- until the correct size tires are rolling on the ground, because the circumference of the correct size tire is part of the speedometer calibration. (5280 feet in a mile, measured tire circumference, #revolutions per mile.)
I can run a car in the air on a hoist with the speedometer showing 100+, but the actual speed is zero because it's not going anywhere..
Changing tire diameter only affects the accuracy of the speedometer (and odometer); actual road speed vs. indicated road speed.
GPS can verify that for you.
HTH
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