I'll forgive you this time. Don't let it happen again.

The valves hit and the lifters really don’t give when it’s running. The one that gave up was probably the closest (hardest hit) due to variances in deck height, but they all made contact and should all be considered a liability. If the valves seal, you’re going to get some RPM out of it and that will increase the chances for failure and even more damage.

Have you seen an engine come apart at speed from dropping a valve head? The damage is usually catastrophic (you got lucky on this).

Personally, I wouldn’t take a chance with it. A couple hundred bucks for valves isn’t a lot of money when compared to replacing pistons and rods, cranks, blocks, heads, etc.

Correct. When running Lifters pretty much hydrolock, except on base circle, when it's check valve opens, and that's where the lash is set. If they didn't, we wouldn't be able to run 180-200 seat pressure and 400-450lbs open spring psi on healthy BBC's. That does not include rocker arm multiplication and the forces while running. The valve will bend with piston contact. Lifter will not help.

I’d also look for bent push rods too.

can you get better pics of the deck?hope its the lighting thats making it look pitted.

Yes. It's the lighting and oil I sprayed on the deck to keep it from rusting. No pitting...
While I was just degreeing the cam I was thinking about the valves. You guys are obviously right about the lifters not having any give. Hydrolocking was a good analogy. I have ones that I already prepped from the original set of heads which are the same size. I'll put the ones that are in the heads now on the valve grinding machine and that will tell the real story. In the mean time I won't have to worry about it. Push rods are an easy check before I install them. I would have done that either way.

Cam degree #s:
Exhaust Opens 47.5*
Intake Opens 3*
Exhaust lift .4828"
Intake lift .483"
​​​​​​Exhaust closes 2*
Intake closes 49*
​​​Exhaust duration 47.5+2+180=229.5*
Intake duration 3+49+180=232*
Exhaust c/l (161+65.5)/2=113.25*
Intake c/l (69+165)/2=117*
(113.25+117)/2=115.125* lsa



​​​​

Not sure it’s just the picture, but what I can see of the bore of number 8 doesn’t look happy either.

Sorry if it seems like we’re nitpicking. Just trying to get you set in the right direction.

That cam is in 2* degrees retarded.
Neutral woukd be 115 icl and 115 ecl
4* advanced woukd be 111icl and 119ecl

Here quote of myself long ago

I keep stressing - use the factory timing set. You’re asking for trouble using what you have. It’s never been right.

Take the timing set off one of the cores you brought back. I’ll bet it works just fine.

I'm not sensitive. If you see something is up, I appreciate you letting me know. The bore in this case is good to go. It's just oil and lights. I put a good coat of oil on everything and it makes it look like hell. Damn VA humidity would turn it into rust in an hour otherwise.

Hmmm... Possible it's just another grind? There's no question about it being in right this time. I know, famous last words. I have pics lol Let's say it is 2* retarded. How do you think that would affect performance? In theory I'd just have slightly more top end and a little less in the lower rpms right?
https://cimg9.ibsrv.net/gimg/www.off...fbf797f7d9.jpg
https://cimg3.ibsrv.net/gimg/www.off...5faa4bd07a.jpg

You bought a multi keyway timing set and cam degree tools for ?

Merc also install their bbc ‘blue motor’ Crane cams 5* advance.

More midrange, less overap after top dead center, to name a few reasons, I’m sure.

edit: calcs were off. I just realized I didn't subtract for ATDC.
I advanced my cam this morning. Here is what I came up with moving the crank sprocket 2 degrees advanced.
Looks like all is right with the cam world now.

Duration @ .050" (2* crank advance)
Exhaust 49-5+180=224*
Int -2+47+180=225*
Valve opens
Exh 49*
Int -2*
Valve Closing @ .050"
Exh -5*
Int 47*
Valve lift
Exh (.284")
Int (.284")
Max Lift. 482.8
CL
exh (167+63)/2=115
int (63+167)/2=115
LSA 115*

https://cimg3.ibsrv.net/gimg/www.off...3862676e6e.jpg

I checked the real ptv clearance and squish tonight. I threw a light spring on the intake and a once torqued down head gasket that's the same as the ones I'm running. .102" int PTV and .066" squish.

https://cimg5.ibsrv.net/gimg/www.off...a1a9a5bded.jpg
https://cimg2.ibsrv.net/gimg/www.off...2bbb8b9d30.jpg
https://cimg5.ibsrv.net/gimg/www.off...fb6a44b5db.jpg

Can you explain how you calculated the 109* ICL? This is what I calculated. I was calculating lobe c/l I thought. I calculated it by coming down .050" off the max lobe lift (.284").

CL
exh (167+63)/2=115
int (63+167)/2=115


Also, why did I need to advance 2*? A stock timing chain doesn't add 2* so does that mean they're all running retarded?

Finally found the time to finish her up. Went out tonight and she's running like a champ. Brought her up to 35, but I didn't want to push her too hard yet.
I started her on the hose and broke her in then changed the oil and filter. Set the timing to 8°. I have a short list of things I want to dial in on the boat, but I can finally enjoy her at least.
Thanks again to all you guys that helped out.

https://cimg7.ibsrv.net/gimg/www.off...2e61dad9c2.jpg
https://cimg3.ibsrv.net/gimg/www.off...704d90613c.jpg
https://cimg4.ibsrv.net/gimg/www.off...c861c12b7e.jpg

Sweet

why is the head gasket out of round?

It's just the way they're manufactured. Good question though. I'm not sure why they do it.

^^^^^^ thats how they are,its the hiperf. set up for when you bore notch the block.it allows the valves to be unshrouded and flow more air and exhaust.

^^^That^^^
Some OE high performance blocks/engines had them.

The 454 mags we’ve built had them (88-90) but my 502s did not.

The smaller bore blocks have more shrouding. 4..47” (502) and up don’t have significant shrouding.

Exactly.

Interesting… the gaskets still have the notch though not as pronounced (I just went and looked).

i've bore notched 502's,not sure if it helped,,but it was quick and easy upgrade.

Put about 100 miles on her today down the York River. I parked my truck and trailer next to someone with an Active Thunder. His blue F250 and trailer were pretty nice. Too bad I never saw the boat.
She didn't miss a beat. Pretty psyched right now. About a dozen or more dolphins even came by to give their blessing. She's not fast, but she gets up on plane quick for a big boat. 4,200 rpms and 35 seems to be wot. I held her at 3,800 and 30 mph most of the ride.

https://cimg3.ibsrv.net/gimg/www.off...30afc821b3.jpg
https://cimg8.ibsrv.net/gimg/www.off...7e39e930b7.jpg
https://cimg2.ibsrv.net/gimg/www.off...7e4db6eae4.jpg

Glad she’s running good for ya!

Thanks Tom!
I noticed she's running a little rich when I was flushing on the muffs last night so it's time to start dialing the carb in a little better. The good thing is I burned through most of the old gas. I thought I was at a 1/4 tank when I got back last night, but it only took 54 gal. I put in 36 gal to top it off before we left. Can't really complain about that after a full day of boating. I'll have to look at my Autometer gauge set up, but I'd rather think I have less fuel than the other way around I guess.
Now to get rid of the greasy hand prints. Dawn didn't cut it. I'll try Simple Green next and then the purple stuff. Once I do that I need to get a good coat of wax on everything. I think it's been a couple years. I'm sure that's why I'm having a ***** of a time with the oil stains.