Impulsive 3.8 swap.

When I get back into this project I'll check the exhaust valve retainers and anything else that may lead to the early failure.
Almost ready to tear back down and find out what happened. When I do put it back together I'm sticking with the Lunati flat tappet cam I picked out. I have a theory that I destroyed the cam/lifters with my dumb actions about adding engine oil through the lifter valley on the cam and my choice of break in EP lube. " I added oil over #5 & #6 lobes essentially washing the EP lube off the cam" this time I'll already have the crank case filled before the new cam goes in and I'll use the really sticky EP paste on the cam and lifters that won't fling off with rotation or wash off with oil.
I don't know what's going on. The intake is off and I pulled the rockers/push rods out, I can't find anything wrong. The lobes in question look new, the lifters were spinning and look almost new. The camshaft as a whole looks good (still in engine) I pulled off #2 exhaust spring and retainer and the valve guide looks stock uncut and with no contact. The retainer also looks like no contact, I did not pull an intake spring off yet. I expected the worst and can't find anything.
With .472 intake and .496 on the exhaust I can guarantee that the retainers are hitting the guides. You won't see any damage to either, but I would bet money on it that they were hitting causing the noise. I would pull the rest of the lifters to inspect, then roll the push rods on a flat surface to be sure they are straight. Pull the heads and cut the guides for Viton seals. TA Performance has .500 and .531 Viton seals. You need to know the size of the cutter before ordering the seals. Various cam company's list cutters. They are sometimes hard to find. Hopefully the cam and lifters are all ok.
My guess for the play in the rockers is that the retainers that hit the guides caused the lifters to bottom out and possibly stick the plunger down. Check the lifters carefully to see if any have a stuck plunger. They are probably ok if you can push the plunger up and down. They should pump up when you start it back up.
I pulled all 12 lifters for inspection, only took pic of two. They all look the same/good so I believe the cam and lifters are good to go still.
If I pull heads off for guide shortening I'll get to play with head gaskets at least.
It sure seems possible to clean and anneal the copper head gaskets and put them right back on without the composite on top.
Not sure why it has both copper and composite gaskets except to lower compression. The owner of the shop I worked at in the 70's ran copper head gaskets on his Top Alky dragster with KB Hemi's in both his dragster and his funny car. He used to heat the gaskets and re use them with out quenching them. My understanding of the annealing process is that you have to quench the gaskets in water and then they become soft again. I did that quenching process with the head gaskets on my race bike back then and it worked great. I'm glad the cam is OK.
I'll pull the heads tonight and hope there are no o rings in the deck or heads. I'll get out of this issue cheaply if I only need a valve guide cutter. Worse case scenario: not reusing copper gaskets will make me get another RJC bullet proof head gasket kit and the valve guide cutter.
TA Performance has valve guide cutters in .500 and .531 for 85.00 and of course, the seals. If you reuse the copper gaskets coat them with some Hi Tack or similar sealer after you anneal them. If you find O rings you may have to use the copper gaskets.
Looks like it has bigger intake valves. Be sure to check the heads for flatness. The two head gaskets were either to make up for warped heads or probably to lower compression. The pistons look like they have some compression built in.
Both the valves are stock with the tulip they say GM they have to be stock size.
Definitely very odd pistons certainly they stacked gaskets to lower static compression.
I ordered a 11/32 × .531 guide cutter and new seals in that size, I'll cut the exhaust guides but will not use seals because I'll still run the stock exhaust valves. Just going to cut guides until I get to the spring seat on both In & Ex.
I tried not running seals on the exhaust valves after cutting the guides. Smoked really bad at idle. I also tried using stock valves with seals. Tore up the seals. Exhaust valves are not too expensive from NAPA. Now would be the time to do it if you can swing the added expense since the valves have to come out anyway. Sealed Power SEP V4168 15.99 each X 6 would be 95.94 from NAPA On Line. They are in stock here in Miami at the DC, surprisingly. I cut my guides about .125 from the spring seat.
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Pulled the odd bank head off tonight and took a much closer look at everything. #1 & #5 the exhaust valves have hit the pistons lightly which I might have done on the very last start when I lengthened these adjustable push rods to get the play out.
No other valve has hit so I think that ones on me.
The heads have completely smooth chambers and I see the intake valves are unshrouded. I'll see what else has been done when they are apart.
This should be in the post above but I missed the 10min edit mark which is dumb.

I look at the even bank and it sure appears that exhaust valves of #6 & #4 have just touched the pistons, I can see it even in my photo's now.
I know what pistons are in this engine now, research was easy. They are Speedpro Hyper H522CP 30. They have a 1.855 compression height, Supposed to be 9.5-9.7 CR with 48cc head chamber.
I've got the guide cutter/seals and I'm working on the heads tonight.
I'll have to see about fly cutting these pistons once I get the head work done.
You will probably be ok on piston to valve clearance since the pistons have valve reliefs. If you measure the piston to valve clearance with clay, be sure to use a head gasket. It makes a difference due to the angle of the valves. I thought I did not have enough piston to valve clearance, then did it again with gaskets and it made a big difference. I used an old hydraulic lifter modified as a solid so the lifter would not collapse when the valve hit the clay.
The exhaust valves are bent so they hit the pistons that much. Perhaps that was the noise I was hearing all along with this camshaft.
The heads end up being the nicest set I have too bad they're not an 8445 casting. They have been ported, new exhaust seats, new guides the chambers are smoothed out. So someone did all this work and put stock valves back in the stock height guides.
I'll get some pics up of them tomorrow
So my research says the Felpro 8723 SP is a shim spacer copper gasket that goes under a 8723 PT composite gasket. Why would someone do that in the first place when thicker gaskets are out there?
Definitely have to check piston to valve clearance and none of the adjustable push rods are bent just the valve.
What timing gears are you using? If they have multiple key ways is there a possibility that the cam is retarded a bunch causing the exhaust valves to hit the pistons? The notches in the pistons look pretty deep and the pistons don't appear to be above the deck judging from the ring travel in the cylinders. I saw some photos of those hyper pistons on the Summit web site.
This has a Kenne Bell double roller with the long chain and uses a damper, I don't believe it had extra key positions but I do know I put the cam in straight up. The old 1XB cam was in the same position