[Ironangel]

The cylinders have been bored .060" over stock. The pistons are a UEM Piston, although cast they are said to be a decent piston that wont frag like a regular cast piston. They're a good middle of the road piston as long as your not winding that motor up to 7K or shooting boost or nitrous to the motor. From the pics they appear to be a low dome and will work great with 781 heads. .015" in the hole is good! The heads are good BBC heads that will make 450 HP in stock form, don't let these drag racers convince you that you need to install bigger valves and port them because unless your racing that motor you don't! One thing I would do is unshroud the valves by matching the tops of each cylinder to the head gaskets, that's an instant 20 HP right there and you never touch the heads. Do some research on how its done and right nows the time while the heads are off. I'll dig up some links and post them if you want, David Vizard is the undisputed expert on these big blocks and shows how simply unshrouding the bores will net 20 HP and help factory heads flow their potential. https://www.musclecardiy.com/cylinde...rmance-part-9/ Never mind all the head work in this write up and scroll down to "Bore Unshrouding" in the pic, the red areas. I'd run the cam you have but beware of the EDM (self oiling) lifters because most are for solid lifter set ups, you have hydraulic lifters and I don't know off hand if EDM lifters are compatible with hydraulic cams. Was that cam and lifters already broke in? In other words, was the motor already broke in when you got it? Heres the important question...Did you keep track of which hole each lifter was removed from so they could go back to hole they were broke in at??? If not, then investing in a new cam and lifters would be a wise decision to insure you don't wipe the cam out and have to disassemble the whole motor for a professional jet washing of the block, heads, and crank. The .525 lift is a nominal lift allowing stock springs and the such and will still make those 781's flow to their potential. Unless your building a race motor I'd keep it hydraulic or hydraulic roller. Comp Cams makes a tool that will cut a groove in each lifter bore that will allow oil to drip directly down onto each cam lobe that does what the EDM lifters do. Another problem with EDM lifters is that laser cut hole is so tiny in many of them that some will clog so beware. I'm running Howards EDM solid lifters in my 439 (427 w/.060" overbore) mated to a Clay Smith solid cam ground for that motor. These particular lifters have .018" oil holes which are considered big holes. I'm running the same exact Melling HV oil pump with welded at the tube, bolted at the pump oil pick up tube. My motor turns 8000 rpm and is a race gas race motor. That tube should be at least "brazed" to the pump body because your motor is externally balanced and they're notorious for shaking those tubes loose. My 427 crank is an internal balanced crank, 454's are not, keep that in mind when you get a flexplate, don't get the internal balanced flexplate! Where are you located? I wish you were close so I could come over and go over some things...You can run any GM V8 distributor in that motor, a small block Chevy dizzy will drop right in and work great as long as it's not bearing down on the oil pump shaft when you lock it down. That's a pretty good set up you got and should run great on pump gas. I cant recall what the chamber volume is on 781's but they are open chamber heads so your CR should be in the 8's maybe low 9's if they've been milled and piston dome volumes fall in the 20's which is low enough for pump gas, high enough to give that big block rumble...