I am down to the final decision of engines to put into my GP .40 size extra 300s. Either a 50 sx or 61 FX. I used the rcu engine comparing thing and it shows that both have a bore of .866" but the 50sx has a longer stroke of .85" when the 61fx has a stroke of only .77". how can that be? the 61 has more displacement, if they have the same bore, then the 61 needs to have a longer stroke, am i right or wrong?? i dont know. maybe its just a typo. anyone have any input? kinda confusing me.

sean