Which would be a better block to build? A 4v lincoln aviator motor or a 93-98 lincoln mark 8 motor? What are the differences pros and cons etc? I know the mark 8 is a teksid block and I've also heard the aviator motor is very similar to a mach motor is this true?

 

Teksid block is a little stronger than the WAP block, but unless you're planning on 1000+ hp then it really doesn't matter. Go with whichever is less expensive and/or easier to acquire. The crankshaft in either will handle 600+ hp, easily.... Rods and pistons must be addressed if you want more than about 450whp.