Drastic Tire Size Change
#1
09-08-2000, 11:51 PM
Join Date: Aug 2000
Location: Villa Rica, GA, USA
Posts: 41
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Drastic Tire Size Change
I've got a 2000 F-150 SuperCab and just ordered a set of 10 spoke, 2001 SuperCrew wheels and tires (new takeoffs, great price too). My factory wheels are 16's and the tires are 235/70/R16. The new wheel/tire combo is 265/70/R17. I didn't think at all about the gear that I am running when I made the order. Am I going to have problems with a 3.31 gear? How far off is my speedo going to be? Do I need to get the computer reprogrammed/recalibrated? I'm not going to be drag racing the truck, so I'm not that worried about loss of HP, but just curious, is my HP loss going to be significant? I'm just now getting used to the Flowmaster and Airaid FIPK mods. Am I immediately going to want to buy a SuperChip to make up for it?
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BigDawg
2000 F-150 SuperCab
Oxford White/Harvest Gold
5.4L V8
3.31 Gear
Husky Liners
Ford Duraliner
FlowMaster 40 Series
K&N FilterCharger
Airaid FIPK
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BigDawg
2000 F-150 SuperCab
Oxford White/Harvest Gold
5.4L V8
3.31 Gear
Husky Liners
Ford Duraliner
FlowMaster 40 Series
K&N FilterCharger
Airaid FIPK
#2
09-10-2000, 12:11 AM
Your systems will be about 7% off.
When the speedo shows 60mph, your actual speed will be around 64mph. As a result, your odometer will only record 93 miles for every 100 traveled.
Your "effective" gear ratio will go from 3.31 to about 3.08. You'll probably notice a decrease in take-off power and "might" see some downshifting on hills?.
It is my experience that a Superchip will help, but only new gears will give back all the "power" that you lose with larger tires.
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1997 4x4 Expedition- 4.6L, true dual exhaust w/glass-packs, K&N air filter, SuperChip, airbox mods, Edelbrock shocks, 285/75R16 BFG ATs, 2000 "XLT" wheels, 4.10 gears, Auburn LS, Clarion In-dash CD player, Smitty Bilt push bars and nerf bars.
2000 4x2 F150 XLT Reg. Cab LWB- 5.4L, Tow Pkg, 3.55LS, CD player,Remote Keyless Entry, Sliding back glass, Special Appearance Pkg., tinted windows, Line-X bedliner, K&N air filter, SuperChip, airbox mods, 285/60R16 Goodyear Eagle GT IIs and Prime #155 wheels.
http://members.visualcities.com/NoMo
When the speedo shows 60mph, your actual speed will be around 64mph. As a result, your odometer will only record 93 miles for every 100 traveled.
Your "effective" gear ratio will go from 3.31 to about 3.08. You'll probably notice a decrease in take-off power and "might" see some downshifting on hills?.
It is my experience that a Superchip will help, but only new gears will give back all the "power" that you lose with larger tires.
------------------
1997 4x4 Expedition- 4.6L, true dual exhaust w/glass-packs, K&N air filter, SuperChip, airbox mods, Edelbrock shocks, 285/75R16 BFG ATs, 2000 "XLT" wheels, 4.10 gears, Auburn LS, Clarion In-dash CD player, Smitty Bilt push bars and nerf bars.
2000 4x2 F150 XLT Reg. Cab LWB- 5.4L, Tow Pkg, 3.55LS, CD player,Remote Keyless Entry, Sliding back glass, Special Appearance Pkg., tinted windows, Line-X bedliner, K&N air filter, SuperChip, airbox mods, 285/60R16 Goodyear Eagle GT IIs and Prime #155 wheels.
http://members.visualcities.com/NoMo