The engine is 526" will dyno it after I return from another trip in a few weeks. It has two problems, I damaged the dry sump pump from ignorance, a $1500 replacement cost will teach me. The other thing is I have a crank case leak somewhere and the vacumn pump doesn't draw a vacumn, have to find that. The headers are from the 66 Mustang, but a new set is being built now. The blue parts on the carbs are the venturi airhorns, have not looked at them closely yet, just put them on. They were built for the engine, worked great right out of the box. Linkage for the splits took about 12 hours, I had to fab some pieces myself to get it perfect with no binding. Everything on this project has fought me every step, RWJ