gas mileage... and coil pack
#12
i agree, I have an SCT programmer and need to recalibrate the tire size and tune the car - but need to find some time, will have to get the ECU code in the footwell panel since the one on the passenger door is worn off...
anyone know a rough conversion for the mileage before I can retune?
anyone know a rough conversion for the mileage before I can retune?
#13
ugh, just filled up 161.4 miles and 12.13 gallons (13.3mpg) and he drives VERY conservatively
http://www.fuelly.com/driver/ryan96/mustang
I'm starting to wonder if the 20" wheel/tire setup is not logging as many miles as needed...
245/35-R20 tires
using a tire size calculator - the 205/65-15 (oem) vs the 245/35-20
the 20" tires will make the speedo 4.9% too slow, so when the speed reads 60mph - we're actually going 63mph
http://www.fuelly.com/driver/ryan96/mustang
I'm starting to wonder if the 20" wheel/tire setup is not logging as many miles as needed...
245/35-R20 tires
using a tire size calculator - the 205/65-15 (oem) vs the 245/35-20
the 20" tires will make the speedo 4.9% too slow, so when the speed reads 60mph - we're actually going 63mph
161.4 x 1.049 = 169.3 actual miles.
divide by 12.13 gallons and get 13.9mpg.
The 20" wheels typically weigh significantly more than stock and put most of that weight far away from the center of the wheel, which means a much larger moment of inertia. This means it takes a lot more fuel just to accelerate them up to speed. Big wheels typically translate to lower city mileage (lots of starting and stopping, when high moment of inertia hurts you), constant speed highway mileage shouldn't be affected much.
What do other people get with these convertibles? We haven't driven ours enough to know.
#14
ugh, just filled up 161.4 miles and 12.13 gallons (13.3mpg) and he drives VERY conservatively
http://www.fuelly.com/driver/ryan96/mustang
I'm starting to wonder if the 20" wheel/tire setup is not logging as many miles as needed...
245/35-R20 tires
using a tire size calculator - the 205/65-15 (oem) vs the 245/35-20
the 20" tires will make the speedo 4.9% too slow, so when the speed reads 60mph - we're actually going 63mph
http://www.fuelly.com/driver/ryan96/mustang
I'm starting to wonder if the 20" wheel/tire setup is not logging as many miles as needed...
245/35-R20 tires
using a tire size calculator - the 205/65-15 (oem) vs the 245/35-20
the 20" tires will make the speedo 4.9% too slow, so when the speed reads 60mph - we're actually going 63mph
Almost everyone notices a drop in mpg when they switch to 20" wheels, especially when stock is 15"! With stop and go driving (90% city) that extra rotational mass is like dragging around an anchor. if you still have the stock wheels, swap them for a tank and see the difference!
#15
#17
These V6's do not really get that good of mpg's anyhow, let alone much larger wheels. GT or other V8 model guys sometimes will say well you got a v6 I bet you at least get decent fuel mileage and I have to reply no, in honesty the v8's do get just as good if not better fuel mileage in many cases. I think I average between 15-17 in town/city, and about 24-25 highway. I don't drive conservative really though.
#18
so we're shopping around for some smaller/lighter wheel/tire combos
#19
I like putting newer, OEM wheels on. I bought these for our '01:
They are from an '05 GT (?). They fit pretty well with no spacers, but there is a little rubbing on sharp turns.
They changed the backspacing for the '05+ Mustangs, so you have to watch that if you get newer wheels.
They are from an '05 GT (?). They fit pretty well with no spacers, but there is a little rubbing on sharp turns.
They changed the backspacing for the '05+ Mustangs, so you have to watch that if you get newer wheels.