thoughts on a 27" tall tire

bdubb

bdubb

I am teh kingpin!
anybody have any helpful hints on running a larger rolling diameter. been looking at tire choices, and the tire i want to run is 27" tall. how bad would it effect gearing?
 
S

smeagol

Active member
If you can find one that fits well, the gearing issue will help, as it will load the motor more.

Problem is that it will probably be more rotating mass.
 
Don W.

Don W.

Stab it and steer it
Some thoughts on taller tires:

If you go to taller tires and don’t do ANYthing else you reduce your overall gear ratio. This has the same effect as going to a higher (lower numerical) gear ratio in the rear, and front, diff. This will, in general, give you less “launch”, and proly slower ET’s.

Speedometer will be different by the percentage of change either up or down. Something usually not considered. If it was correct at 60mph, taller tires will give you a faster truck and maybe an unexpected ticket. Or, like some certain other drivers, tiny tires giving them outrageous indicated speeds when their actual speed is slow. Is this why they’re always pokey in the slow lane? :)

With taller tires you’ll have a lower RPM at speed which -may- equate to slightly better highway mileage.

Don
 
ghettosled

ghettosled

SYTY SUPERSTORE
Don W. said:
Some thoughts on taller tires:

If you go to taller tires and don’t do ANYthing else you reduce your overall gear ratio. This has the same effect as going to a higher (lower numerical) gear ratio in the rear, and front, diff. This will, in general, give you less “launch”, and proly slower ET’s.

Speedometer will be different by the percentage of change either up or down. Something usually not considered. If it was correct at 60mph, taller tires will give you a faster truck and maybe an unexpected ticket. Or, like some certain other drivers, tiny tires giving them outrageous indicated speeds when their actual speed is slow. Is this why they’re always pokey in the slow lane? :)

With taller tires you’ll have a lower RPM at speed which -may- equate to slightly better highway mileage.

Don
Click to expand...

actually you would (in some cases) want a taller gear so it doesnt hit the tire so hard out of the hole (less wheelspin), and also allow you to run less then 5000rpm through the traps with a stock motor which is well past its peak hp curve. For those guys trying to go 130s its pretty hard on a small tire without reving the piss out of the motor.
 
G

GM TURBO

Sell Out
The only problem with Dubb's 27" tire is it is a 25-series. Not gonna be much sidewall flex in those.

Too many factors really to determine good or bad.

Since BW doesn't race his truck it is gonna look sweet rolling dubbs.
 
Don W.

Don W.

Stab it and steer it
ghettosled said:
actually you would (in some cases) want a taller gear so it doesnt hit the tire so hard out of the hole (less wheelspin), and also allow you to run less then 5000rpm through the traps with a stock motor which is well past its peak hp curve. For those guys trying to go 130s its pretty hard on a small tire without reving the piss out of the motor.
Click to expand...

Exactomundo, compromise, why do we always have to compromise?? :)
 
You must log in or register to reply here.
Top