Lucy,
I don't think the smaller tires would have any effect on track recorded speed. It may not match your speedo but it would be accurate. Smaller tires would, however, be the same as changing your 4.10's to something like a 4.30. When you change the diameter (which changes the circumference) of the tire it changes the overall ratio of the drive train. And no, I don't mean that it makes a physical change, it changes the mechanical advantage. Smaller tires increase the mechanical advantage and larger ones decrease it.

 

Technically the size of the tire matters, Lets say your riding on 20 inch rims The wheel is gunna be much greater, and you loose HRp and Tourque, WIth a 16 inch rime tire is smaller allowes the engin to beable to turn the tire much more easly, But too small and youll just spin them and get no traction, So its all up to you wetther or not what size, Id stay with a light weight 16 inch rip with Low profile tire

 

I like the FRPP. I just walked in and bought them over the counter. To the poster ---My 80mph is at 2900ish rpm. & 70 mph is 2500ish. No big deal to me with 75% highway driving. I lost 1 mpg with the switch. No problems with the FRPP 4.10's ,I'm happy.


praztek--- I agree that it is not your gears but the clutch paks. Mine did the same thing until I had Ford replace them.

 

mabye sea level has somthing to do with it. Im in San Antonio(700ft above sea level)I ran a 13.49 last week on just a tune/CAI(stock tires). Mabye you should move closer to the coast???

 

Hey guys...im a NOOB with all of this...but i just got a 2006 Mustang with 4.10 gears, borla exhaust, eibach lowering springs and some other mods...i just had a few things to ask ya'll........i dont know if its the changing of the gears to 4.10, but my speedometer is showing faster than im going and my mileage has increased.....a trip that usually takes me 195 miles in my old care now takes me 220 miles......this is going to run up miles on my car pretty fast if i dont get it changed....the guy at the ford dealership told me that the 4.10gears arent covered under factory warranty(obviously) he said it would cost him $90 to even go back and look at the comp......i was hoping you guys could let me know what the deal is.

 

You need a tuner to make the gear ratio change, either SCT or Predator.

https://mustangforums.com/m_800831/mpage_1/key_/tm.htm

 

hey thanks praztech.....how much do you think those run?

 

Im between 3.73s and 4.10s. How big of a difference, and what would you guys recommend?
Thanks!

~Eric~

 

Maybe you should also just look into 3:73. Its just a thought.

 

I just read this entire thread and found it enlightening especially that top end part where you may actually do better against the drag however he said not a stock mustang with gears but a modified one. Anyway my car is a hot rod and I wanted to prove that this morning when a Z-28 was behind me but damn traffic on the interstate was crawling because some damn ******* caused an accident.