I have a 59 172, and have always liked the Cessna fastback/straight tails. I would like to have a solid IFR platform for some cross country trips, and am wanting to upgrade to 175/182, but not sure if a 175 is much better than my 172. I am weighing upgrading my 172 to 180 hp, or selling it and investing in a 175 with either the GO-300 or 180hp....will I gain much my switching airframes besides the power from the bigger engine?

The 175 will have a larger instrument panel than your 172 and higher gross weight.

Is the gross weight considerable? Also, I have been reading on this site, that with the GO-300 you do not want to let the plane push the prop, and you want to carry power ( approx1200rpm)through the landing, how does that effect your short field landings?

Rich,

It is true that you always want the prop pulling the plane. With the correct techniques short fields are not an issue. Monday evening I took off on a 1600' grass runway with full tanks and just my large body onboard and was off in pleanty of time to easily clear the trees and houses at the other end.

The 175, 175 A & B have a max gross weight of 2350, the 175C is 2450 and the P172D is 2500.

There are quite a few engine STC options currently out there and at least one more in the works.

I have been flying a 58 with the GO-300A, Micro VG's and gap seals for about 7 1/2 years now with no major issues.