Marine 273 build

BillGrissom said
Those cams don't sound big. I put a 0.422/0.444 hydraulic cam in my 1965 273, and it is termed "RV/Torquer", i.e. good for low-end torque. You can tame a big cam with Rhoads leak-down lifters, but they are "all in" by 3000 rpm, so probably not needed in a boat. The 273 excels on the high end, like 7500 rpm, but should give good power at your lower limit.

The cam specs look tiny to me too... but my eyes are not calibrated to small block Mopars. I have a bit more experience building small block Fords and big block Chevies. It seems that both small block Chevies and small block Chryslers can make some big power at higher RPM even with small "looking" cams. Like the 5200rpm 235hp Commando with a .425 cam. As I said, the .429/.444 is the stock HO 340 cam. Of course, this is all neither here nor there, as those are the options we have- and thats it!

BillGrissom said
Pistons are the killer price, especially if forged, which your friend likely found when buying the Egge's. You won't find a set for $90 like a Chevy SB. Your engines likely had the HiPo Commando pistons, since came with a 4 bbl. When installing them, note that most sets have a "left" and "right" bank. Some racers would swap the banks for better performance. You can read some posts here. Either way, keep the same bank set together.

My buddy is doing a real rebuild and didnt have a problem justifying the cost of the Egges... I, on the other hand, am not planning any real engine work on this boat and am on a shoestring budget! If I can do heads and an intake cheap, then I will consider it.

Regarding the Commando pistons, Im afraid the marine engines were not so equipped. All of the manuals I can find from that period show lower compression, lower flowing, low RPM engines being the norm. Peak power was rated at or near 4000rpm, and even the mighty 340's got lowly 318 heads and dismal (250hp) power ratings. That is consistent with the rest of the marine industry at the time- 240hp Ford 351w's (8.5:1 CR and 4400rpm peak power) were the gold standard as far as small blocks go, into the early 90's.