Check
MandarinaRacing and, I think,
Import Killer. They have or are palnning to use the Holley 2-bbl baseplate, I think. It can be redrilled to suit the Weber carb base. The kit isn't common in Oz, but if you talk to the right people, you'll be sure to get some great results.
Strike a friendship, and they may share some trade secretes!
As a rule of thumb, the stock cast pistons used on most American cum Aussie I6's can cop well over half the original Hp the engine kicks out. So a 75 horse shot won't hurt at all.... :roll: but its the old story. If thats what 75 is like, how good will 100 be?
The head gasket and head bolts will need attention before you go any further. No2 will show up any weakness. The Alloy head has one if the head isn't in primo condition. Rust is the key problem, and seldom do guys use the rust inhibitor Ford state you must use. 9 out of 10 cross-flows will alloy heads I've inspected are rusted at the rear cylinder. Do something so it won't make you a slave to its own agenda.
If you've got bucks to blow, this is an opportunity to use the O ringing process, either gas filled Wills rings, or copper fire rings, with the right steel/composite gasket. Isky used to offer a kit for a few bucks, but a couple of cylinder head failures will cost you. Copper gaskets can be used if you are prepared to use a sealer. They always leak and weap, but save on teardowns. There is a long term pitting issue with these gaskets
