International 250 road speed

[ap7610]

a friend has a 250 McCormick international which he intends to use for road runs but in comparison to his 275 he finds her top road speed quite slow, is there anything that can be done apart from changing the wheels to make her faster?
He wants to try to keep the tractor looking as original as possible, Ive heard of tractors having gears changed etc to increase speed in more modern tractors. Tia

 

[REStracTORATION]

The 250s don't have hi/lo box
So diff alterations possibly
Gear swapping might be more an arse for little gain
How easy it would be to put a hi in then remove lever etc

I'm just guessing on the above there could be simple way I'm sure someone will know

 

[startinghandle]

what condition are the brakes and steering on your friend's 250?

 

[ap7610]

what condition are the brakes and steering on your friend's 250?

The brakes are as new as he refurbished them, I actually never saw brakes as good for that era of tractor in comparison to my 135 anyway. Steering will also be in good shape as he plans to do it up aswell.