Trans- Am motor

[9dodge]

Quick question,
What motor did Mopar use in Trans Am racing of the 1960? It was a 305 CI rule right? How did they achieve that?
I was just thinking about it and thought I would ask.

Thanks

Michael

[sanborn]

I think they ran in the late 60s. They used an "M" block (heavy wall 340), with 4.040" bore and 2.96" stroke to give 305". The heads were like the "X" but with offset pushrod holes. The intake rockers were offset also, chilled iron like the 273s. The rockers were bushed. Valves were 2.020"/1.600". They standard camshaft was a Racer Brown ST-19. The intake manifold was a 2-4 offset like the staggered Max Wedge intake. Two Holley 600s were used. Compression was 11 to 1 (I think) and I remember the pistons were forged with "Alcoa" forged on the bottomside of the piston. The piston was a flat top but came out of the block about .060". The rods were a forging but not like a stock rod, they were 6.22" in length with standard sizes on both ends. I think I still have 4 or 5 rods in the plunder pile. Horsepower was 410-420, pretty good for that day.