543

Yes u need bigger heads for a 540. The 6s will be the choke point even if they are max wedge ported. I have Indy SRs and they still are not big enough to support 540 cubes. I know a guy that used ported stock port Victors. He says it dynoe’d over 800 hp. He has a 69 Charger that ran 9.69 last weekend. Kim