85 MPH / 140 KMH on 645ci
04-19-2009, 01:36 AM
#1
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Hi members, I need your help.
I need to know how many rpm your clock shows at 140 kmh of speedometer. Or 145 or 150, it is the same.
Or, if you prefer, which speed the needle shows at 3500 and 4000 rpm in 6th gear.
Obviously in 6th gear.
Important: 645ci SMG or manual. Maybe also 650i can be good, if gearbox and final ratio are the same of 645ci.
Thanks!
I need to know how many rpm your clock shows at 140 kmh of speedometer. Or 145 or 150, it is the same.
Or, if you prefer, which speed the needle shows at 3500 and 4000 rpm in 6th gear.
Obviously in 6th gear.
Important: 645ci SMG or manual. Maybe also 650i can be good, if gearbox and final ratio are the same of 645ci.
Thanks!
04-20-2009, 12:39 PM
#3
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My Ride: 2004 645 Ci, Individual Stratusgrey Metallic with individual grey leather
Individual Stratos metallic, Shadow line, Black Individual leather, 19'' ellisoid, Panorama sunroof, PDC, Dynamic drive, Adaptive steering, Adaptive headlights, Voice control, Logic 7, Prof sat nav, BT phone, TV, Heated Sport seats, Ski sac, light pakket, CD-changer.
Mods (so far): iPod interface, K&N Airfilter.
Why you wanna know....????
Calibrating a M6 tacho?
BTW: I have a step also
Calibrating a M6 tacho?
BTW: I have a step also
04-22-2009, 11:25 AM
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My Ride: (USA) 645Ci, Silver Gray, Chateau, Cold Weather PKG, Premium Sound PKG, Sport PKG, Step, NAV [Std Equip in 645], HUD, Satellite (SIRIUS) Radio, Aux Input, Bluetooth enabled using iPhone 3GS w/ adapter cradle - Build date - 01/05, Baby delivered 2/24/05
I thought we already did this, no?
Anyway, here is my chart for all three cases. I am in a STEP and can verify the theoretical numbers are so close to my actual that I can see no difference. Obviously if you change tire diameter from OEM that would have an impact but otherwise this chart is valid.
If you cannot interpolate to the MPH you want then use these formulas:
mph to kph = 1:1.61
kph to mph = 1:0.6214
so 140 kph = 87 mph
plug 87 mph into formula gets 3077 rpm for 140 kph for manual/smg
MPH = RPM/(Overall ratio[Final*Gear])/336*Tire Diameter
RPM = MPH x overall gear ratio (tranny x final) x 336 / tire diameter
Note: Tire diameter used is 26.7 inch from Bridgestone data sheets for OEM Sport package tire.
Anyway, here is my chart for all three cases. I am in a STEP and can verify the theoretical numbers are so close to my actual that I can see no difference. Obviously if you change tire diameter from OEM that would have an impact but otherwise this chart is valid.
If you cannot interpolate to the MPH you want then use these formulas:
mph to kph = 1:1.61
kph to mph = 1:0.6214
so 140 kph = 87 mph
plug 87 mph into formula gets 3077 rpm for 140 kph for manual/smg
MPH = RPM/(Overall ratio[Final*Gear])/336*Tire Diameter
RPM = MPH x overall gear ratio (tranny x final) x 336 / tire diameter
Note: Tire diameter used is 26.7 inch from Bridgestone data sheets for OEM Sport package tire.
04-22-2009, 11:33 AM
#5
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Originally Posted by cobradav' post='855448' date='Apr 22 2009, 03:25 PM
I thought we already did this, no?
Anyway, here is my chart for all three cases. I am in a STEP and can verify the theoretical numbers are so close to my actual that I can see no difference. Obviously if you change tire diameter from OEM that would have an impact but otherwise this chart is valid.
If you cannot interpolate to the MPH you want then use these formulas:
mph to kph = 1:1.61
kph to mph = 1:0.6214
so 140 kph = 87 mph
plug 87 mph into formula gets 3074 rpm for 140 kph for manual/smg
MPH = RPM/(Overall ratio[Final*Gear])/336*Tire Diameter
RPM = MPH x overall gear ratio (tranny x final) x 336 / tire diameter
Note: Tire diameter used is 26.7 inch from Bridgestone data sheets for OEM Sport package tire.
[attachment=99868:645_545_RPMvsMPH.jpg]
Anyway, here is my chart for all three cases. I am in a STEP and can verify the theoretical numbers are so close to my actual that I can see no difference. Obviously if you change tire diameter from OEM that would have an impact but otherwise this chart is valid.
If you cannot interpolate to the MPH you want then use these formulas:
mph to kph = 1:1.61
kph to mph = 1:0.6214
so 140 kph = 87 mph
plug 87 mph into formula gets 3074 rpm for 140 kph for manual/smg
MPH = RPM/(Overall ratio[Final*Gear])/336*Tire Diameter
RPM = MPH x overall gear ratio (tranny x final) x 336 / tire diameter
Note: Tire diameter used is 26.7 inch from Bridgestone data sheets for OEM Sport package tire.
[attachment=99868:645_545_RPMvsMPH.jpg]
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