UPDATE:
Took my heads to two different shops today and got two different methods of repair. Now I am confused and could use/appreciate some advice. Both were reco'd by CF members

Shop #1 - machine shop servicing many local repair shops
pressure test heads to look for cracks
replace all guides with new guides, not a thin sleeve
cut top of guide so a seal can be attached to it
replace all exhaust valves
Insert new exhaust valve seats - said this was needed to run unleaded (i already do)???
cut both valve and seat to match
check all spring pressures and heights - replace whats needed
NOT replacing intake valves
.010 cut across the bottom of the head to true the surface
clean & paint
price: $860
reco'd a thick fel pro that would lower compression.


Shop #2 - Guy builds race motors - full shop in his garage.
Drill guides and put in thin bronze sleeve
replace all valve, intake and exhaust
replace all springs
grind valve seats to match valves - without inserting new material/seats
no milling/cutting of the base
clean
price: $375

My confusion is the valve seats. Why is shop #1 putting a new valve seat in when shop #2 is grinding the valve seat? I was under the impression these heads didn't require leaded fuel. Is one of these guys overlooking something or wrong? Shop #1 warned me several times that when replacing the valve seat that he "could hit water and ruin the head". He said it rarely happens, but it is a possibility due to how the head was cast, that there could be a sand pocket......

casting # on heads - 3973487

Would like to know your opinions

 

I pulled a few of the lifters and they are all flat, like perfectly exact flat. Does it make a difference that this is a solid lifter motor? Or do these need to be replaced?

 

Flat tappet lifters, whether hydraulic or solid, need to spin in their bores or they would wear a groove in the face. The cam's lobes are also tilted a little to 1. keep the cam itself pushed back toward the distributor gear and 2. to facilitate the lifter spin. If your used lifters do not have that slight 'hump' in the middle of the face normally called the 'crown' then they are junk and need replaced. But you must use a thin bladed steel straight edge to do the checking as the crown is very slight.

 

Yout 1971 heads already have hardened seats originally installed and yours have 50,000 miles. No need to replace seats unless there is an obvious problem, likely no issue. Checking for cracks is mandatory and inexpensive. I would resurface them. This is usually an $80 charge. I would use a felpro 1094 gasket. Replacing all valve springs and checking install height and spring pressures is mandatory. Shop # 1 is obviously trying to rip you off on the seat replacement and reusing 40 year old solid lifter springs when you know there are issues there and "replacing what is needed" throws up red flags for me.
I would use shop #2. He is replacing all parts needed with new. The valves are likely can be ground, tips dressed and reused but with shop rates the way they are replacement is probably a wash.

 

The lifters abolutely have to go back in the same bore they were removed from. Take the lifters from each set and put them foot to foot and hold them up to a light. You should see a slight convex on each face. Do this with each set and place them back on the table in the order they were in. Again do not mix them up or swap, the lifter is "matched" to that specific lobe after original break in.. If any are different or flat the cam and lifters will have to be replaced. Do not try to replace lifters only as the odds of a sucessful break in with new lifters on an old cam are minimal.

 

I don't think either shop is a good choice - #1 is certainly out, but I'm also surprised that shop #2 is grinding valve seats. Top-notch shops cut seats vs. grinding. Those machines are too expensive for a home shop, but if you've ever seen Serdi-cut seat they're pretty amazing. Personally - I would look further.


I'm not an NCRS guy but I thought the '487 casting number were over-the-counter replacements for LT-1 heads...? I didn't look up the number, that just came out of my head...which means it's questionable

 

Billla,
I may have gotten my terminology wrong. It def could have been "cutting" on the seats versus the "grinding" I stated in my post.

I genuinely thank both yourself and mako63 for hanging in there with me on all these questions. Very much appreciated