More high speed power needed

[viceroy]

After some friendly racing against some very strong machines, it seems that my 172 is very strong in 1st and 2nd (which implies that I have a nice strong motor), but once I get to 3rd I just dont seem to have the same sort of grunt and slowly start losing ground.

what could I do to the engine to keep up at higher speeds?

 

[Nick Read]

Tape over all your shut-lines, remove the mirrors and aerial, slam it right down to the ground and stick a big front splitter on, plus experiment with larger or smaller wheels, depending on whether your engines got enough grunt to push a higher final drive, or it needs a helping hand but attains less outright top speed by having a lower final drive.

 

[viceroy]

You think the 205/45 16" wheels could be the cause of my highspeed slowness?