Seems like this is what the "Half Breed" engine is, A GT5 lower with the same dimension rod as the zaf50 rod and then a Type A piston and jug, only difference is the ZAE50 cranks have wider counter weights.
I'm assuming the the Half Breed is easily made into a GT5 by simply using the type b piston and the Type B jug or just milling the deck down on a Type A jug.
Fred told me that the Type A PK-80 jug works great on the GT5 lower after about .100" is taken off the deck, he said the port timing works out very good an this combination.
I was thinking by him telling me this that the difference in deck height was the main difference in the GT5 jug and the Pk-80 jug.
I have the GT5 lower I purchased from YesImLDS sitting out in the shop still, I have a GT5 jug and several pk-80 jugs so I'm gonna put a Type B piston on the rod and do some visuals between the two different jugs when sitting on the GT5 lower, I want to see if both uncover the ports the same amount at TDC and BDC.
I'm wondering if Fred told me this because the pk-80 jug places the ports a tad bit higher when on the GT5 lower than they are when the GT5 jug is on the GT5 lower...hmmm
If I have time tomorrow I'm gonna have to see for myself what the deal is here.
