Matt75
Here is a thread on TurboSport about longer rods with shorter pistons.
Cheers,
Matt
You will note what he says in relation to port size and rod ratio, and also note that a Pinto has an oversized inlet port to begin with. You will also note that the 5.7" rod he refers to is being used with alloy heads to get big power with a specially desgined port and cam to suit the longer rod, neither of which is relavant to your conversion. He would also appear to be just reading what other people are writing, and not doing his own developement work.
What works with one engine may not work on another. It's about getting the right COMBINATION of parts to make it work correctly as I stated previously. Any one thing out of your combination thats not right will cost you power.
Woz