You have to have your expectations set correctly when modifying a slant. If you look at the formula for torque (then calculated HP) it is _directly_ proportional to displacement then the rest is almost second order. You will still have less than a 250 cu-in engine with the slant so if you are expecting drag race fast then it is way cheaper to add cubic inches with a V8. If what you are after is a nice running engine that can easily keep up with today traffic, can create enough torque that you don't think twice about gassing it to pass and know it can it, be a lot of fun in the open road high speed corners with the low end torque (that is what you optimize a slant for not for high end HP) and want something that can still pull 20 MPG so you can use it for a cruiser and not break the bank then that it what you will get buy updating you slant. I have built 225, 318 and 360 in different A bodies and for just driving around and enjoying the day I will pick slant every time.