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Hi guys

I took off the head of the 359 l8 found out i had a leaking exhaust valve in cil 3 a coolant leak into cil 5 and a ticking lifter( only when engine was hot )

Now iv'e had the head checked and they took 0.30 (mm) off it to clear some oxidation en marks om the surface off the head.
I've lapped the valves with the lapping paste all 16 some only for a bit others like ex for cil 3 and intake 4 and 5 need some more work. Ex valve from cil 3 did not seat good all the way and the other two had more pitting and very nasty intake runners it sucked up gunk from the brake booster hose (leaking brake booster). But after all of this ive installed a gaugetool ( lifter with no spring that has the correct hight)for checking clearance the 0.030 to 0.070 (inch). Set the piston to tdc of comp stroke check clearance but a lot of valves have more then the 0.070 how is that possible? Could it be the car was running with higher clearances and run fine? I've checked the lifter tool for correct dimmensions thats good got pistons on tdc of comp stroke the valves have been out for cleaing but all are in the spot they came out of. Lapped the valves so i thought there as to be some valves that would be under 0.030 so should be ground down a bit. But checked like 6 or 7 valves not yet all of them 2 came in just a bit more then 0.030 (good) but at least got 4 that are above 0.070 inch.

Not sure, but how are the guide tolerances doing?

That does seem to be backwards, if anything I would expect there to be less clearance. You may want to consider replacing a few valves. Maybe someone previously ground the stems and ground them too much??? How much more than .070" are they? On a positive note as the valves & seats wear your clearance will get better.

I would agree with HPH, check the valve guides for wear. I had some very worn guides on my 327. I think the valves on these engines did not always get good lubrication and are prone to wear. Also check your valve stems for wear, I had some that were worn on one side.

Did you clean and test your lifters? Replacing some?

I dont know how to check/measure but what i can feel by hand the clearance is a fair bit😄 and yes maybe drive with this a bit more and the valve clearance willcome closer to the 0.070 😅 could it be someone did work on the car in the past and maybe grind down some valves but to much or had wrong clearances in mind... i was in full ok now i have to grind down 16 valves mode did check 1 cilinder 3 times. Tdc yes comp stroke yes got the right gauges.. damn grinded valve seats but stems still to short.

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I'd consider recutting the valve seats for those cylinders which still do not seat easily after lapping.

If you're referring to valve guide clearance as being a fair bit then you should probably replace valve guides. You can get a set of small hole gauges off Amazon for not much money. You'll probably find that the valve guides have an hourglass shape, and I'll bet cylinder 4 & 5 exhaust valve guides are worse than the others.