Bought boat knowing it needed work. Knew pump needed rebuild, was assured motor is like "new"  mad dash to get pump built before memorial day. Get pump back 2 days before we were about to go.never had a chance to run motor.  find # 3 cyl is dead.0% compression. Say f*ck it and run boat all weekend on 7 cyls. Figured I'd run it till it blows, get home and pull head to find dropped seat,cracked head, and bent pushrod, new heads,pushrod and gaskets,ran boat at elcap yesterday,popping thru carb... pull # 3 wire popping goes away...bad cam.. another problem is the oil psi seems funky? Guage was broken when I got it so I replaced it with another I had lying around. Psi fluctuating from 80-10 psi ? Changed sender now 60-10 under load? I'm hoping this is not an accurate reading ? Going to try new guage with sender before swapping cam. If still no good anyone have a match.....
Just trying to get it through the season while building my 496.hate to keep throwing money at a turd.

theres an old saying.... "slow down, you'll go faster in the end..."

Worse part is I sold my old boat at a loss to "upgrade".    that boat was a solid runner never any problems.

Have the block hot water pressure tested, not just the MAG powder stuff.

Just trying to nurse it through the season. Got a whole other motor I'm building for the 496.

Lake test was a bust.  Was still popping. but....The next day Swapped the distributer out for a different one. Finally success!
Runs great! Only issue is the oil psi starts at 70 then drops down to 15 under load?

Dooley 10qt pan.has about 9.5 qts in it.

A Dooley 10 qt pan does not hold ten quarts....   

To get a Dooley to hold ten quarts of oil you really need a really nice windage tray like the flat Teflon coated Moroso one or the Hamburger tray.

Your crank is whipping your oil into a frothy, hot mess, bet the pressure came right back when you backed her down...

....this, or the oil pump pickup isn't sealed to the pump and its drawing air at higher RPMs.  My white boat did Exactly this ....  Oil pressure would rise to about 70psi until 4500 and then go back the other way to about 15psi at 6200rpms.  Welded the pickup completely, problem solved

Really just trying to me through the season. Would dropping the oil level help?( don't want to pull the motor...)

In my personal opinion, try pulling about 1 1/2 quarts and running it again and see what happens...

Otherwise you will need to follow lbhsbz and take a look-see at the pick up tube, you should be able to have the motor out, pick up checked and back together in less than a day, if you hurt it, not so much...

Good luck.

GT

I know.. We have a hoist. Couple hours. Just want to be lazy....

It seems to have gotten a little better. Cold idles at 70psi,after a good warmup and take off it jumps to 80psi then slowly drops to 20psi at full throttle,when I let off she'll idle at 40psi hot. only 8qts of fresh 20/50 valvoline vr1 oil in the Dooley 10qt pan. Checked oil while running didn't seem foamy,also checked it right after a full throttle run. Is 20 psi o.k. To run?