How much can comfortably be milled off the deck of our cylinder heads without causing any issues? I'm replacing all the gaskets on my 5.9 and figured it would be a prime time to shave them down a little bit. The engine has 168,000 on it so it won't hurt anyways. I'm not doing a cam swap, although I would like to but it's just not in the budget. Ideally I would like to give a slight bump in compression.

I'm thinking if I could get away with 0.020-0.030" I would do that. Also if I mill that off the deck I have to mill it off the intake mounting surface as well right?

 

In all reality, you can't get away with milling them at all. The deck castings were already far to thin when they were brand new.... If you are pulling the heads, instead of wasting money on them, you should simply replace them with better heads. Odessa/Clearwater cylinder heads off of Ebay are NEW castings, with thicker decks. Much better than stock.

 

I had a feeling you'd say that lol. I am aware of the new heads but would prefer not to spend the money on them. The engine ran great before so I suppose I could always just put it back together with new gaskets and run it.

 

I would recommend that before I would suggest milling the heads. If you wanna bump compression, go with a thinner head gasket.

 

Any chance you have a part number for a thinner gasket? I was otherwise just going to purchase a felpro head gasket set from advance auto since it includes all the intake gaskets I need as well. Worst case senario I just check the heads for flatness, clean them up and bolt them back on. I plan on putting a tuner on the truck once it's finished so that should help open it up some anyways.

 

Personally I would go with a better head. PIE has a fully assembled set of iron rams with 2.02" int valves for $1500. http://bhpconcepts.com/newPIE/prodde...nstealthlevel1

 

You can get regular EQ heads cheaper.

 

No, I don't have part numbers, but, I bet Fel Pro would be able to help you out. Might give em a call, or email, and see what they have to say.

 

Yes you can. But take it from someone who put a set of standard EQ's on and regretted not getting the 2.02" int with porting and regretted it later.

Not trying to be pessimistic here but I had a set of heads checked out by the local machine shop and he had yet to see a set of factory heads that at least one was cracked and/or had a repaired crack. He also said that because of where they crack you usually don't see any issues.

 

So at how many miles do the heads crack ? I just scored a 01 5.9 from work that has blown head gaskets but has only 171,000 miles on it !