btw,,those red heads made 1200hp and went into the 47' wellcraft.and there still running.also refreshed the owners 1075 heads that go into his 46' outerlimits.we figure we have run the length of the east coast at 5500 +rpm.:D

Cant argue with results.

What do you run for guide clearances on your marine engines ?

.0015 intake and ,0022-.0025 exhaust depending on hp level.

What do you mean ...He runs em out of the box.. :D

So putting them on out of the box ready to run custom ordered is not advised...???

I check everything and make sure it's what I ordered
And yes I have found things wrong with every aftermarket head
So it pays to check them out

Really? I live in NASCAR country and have been in many of the shops. Quite a few Serdis around those shops. NASCAR might turn right only once a year, but they are still high level engines.

Next time I will just order bare a build them, then I know what they are.... Lesson learned... No reason to buy assembled heads if you have to take them apart and make them what you wanted...

I remember you saying they were tight. What did your valve stem and guide diameters measure out to? Stem issue or guide issue?

Valve stems can vary from one manufacturer to another so it's really never a stem issue unless of course you have one odd ball...which is why it's always good to check them all. Typically you just size the guide to the stem, whatever it is. If the valves are used, then of course they need to be measured for wear.