I think just about all of the 87-95 sbc didn't use exhaust valve seals.

FYI I have not run valve seals intake or exhaust in my marine engines for the last 15 years, my car engines do have them! It depends on what school of thought you have been trained on and more important your particular induction system. I like it when people laugh at me when I start my boat after sitting rafted for hours. (Blue Smoke) I tell everyone the engine is real tired and needs a lot of work ........they never ask again!

back in my drag race days i ran blown alcohol,never had valve seals.i also have done some blown gas engines with no seals,i did not want to post it because lately around here if someone disagrees it seems to start a chitstorm so please dont tell me about what your super builder said.I DON,T CARE.

Contrary to what some say, Mike is no rookie. Abones is another extremely knowledgeable man who has been around engines a long time. No "crap" there.

the real diff is it takes 100k plus miles to make guides wear enough to smoke all the time. we don't generally wear engines out in boats, cept for sportfish that run out to canyon and back constantly. we either break them or get water in them and break them. but i am running a set of L29 truck heads with some guide wear so i am taking a belt sander to a set of new valve seals and looks like i get 600 free travel till retainer hits seal. will give me about 060 clearance. and on that note, once a hyd roller lifter is pumped up, is there any diff between lobe lift times 1.7 and the actual distance the valve travels?

cheeper lifters can bleed down so while the 1.7 ratio does not change,the actual amount of lift can be a little less.

OEM lifters qualify as cheaper ones? about what percentage do they lose? and long as i have you on the phone, i think you have a set of mag standard pistons-rods you are willing to part with?

i don,t know the answer to the first question,yes 365 mag pistons&rods.they look good,no damage,did a build for another oso member and these are the takeouts.

Well I stand corrected... I know some run with no exhaust guides, but was of the understanding that if non were used on the intake, you would suck oil in the combustion chamber & raise the chance of detonation.
Also I am not one of the peeps that think Mike is a rookie... I like to read all his posts... not saying that I agree with all of them,LOL... But I can tell he has been around the block. (no pun intended)

The beauty is we all don't need to agree, but we all can learn something from each other.