i think the efi cam is the same as the carbed cam except for a wider lsa.

nope,,efi cam is 230,236 carbed cam is I think 222,228

just shows you how effiecent a carb is at making the numbers,,less cam.

HP500 Carb Camshaft. 222/230, .576/.598 110LSA

500EFI camshaft 230/236 .598/.610 114LSA

I wonder what was behind Merc's choice on the HP500 cam. They were known for reversion with the 110LSA. One of the only cams I've seen in a mercruiser/mercury racing engine with a 110LSA.

i knew you would post up the info faster than my old azz could find it,lol.

Hmm lots to think about I found a set of 088 heads with 30 hours on them for 450. I am thinking about going with the 500efi cam. I know I will need to change out springs to match the roller cam. But will I see any real gains with the 500efi vs the 420 cam

i would say that the tighter lsa had something to do with it.

not sure how much power gain but flat tappit cam is old school.the hyd roller setup is the way to go.

no way,icl of 106 and 8 degrees less.carb cam kinda sucked from the get go,,but swap it out for a 731 and the motors really responded and didn't revert at 850rpm.

Ok so who wants to sell me a 500efi cam with lifters and rockers for a very very good price as I am just a poor guy doing a low cost build