Hi,

I'm very new here and a new Suburban R2500 1989 6.2L Diesel truck owner. But I have buyed it with a part disarmed engine.

Now, I need to know if there are an over sized valves (inlet and exhaust) because one of my cylinder head have some over sized holes for the valves and no valves guides for replace.

I would be thankful for any colaboration about this.

Excuse the off topic, but I have to ask...Where are you from?

Sorry but,... is here a "come from" requirement?

The 6.2 engines have two different size valves. L.D. 10 series with EGR came with small valves. 20/30 series Large valve heads & had cracking problems so were discontinued. I reccomend you match up a set of small valve heads,recondition as necessary. Small valve heads have increased low RPM torque & throttle response . Will generally deliver better MPG per my expirence.

Sorry but,... is here a "come from" requirement?
No need to be offended, I just detected a hint of an "accent" in your typing and was just wondering where you were from. I like guessing where people are from, and my first guess is Canada!

Worn valve guides can be repaired and resized by any competent machine shop. Bronze inserts can be installed. The aftermarket even has complete guides that can be installed. Again, by a competent machine shop.

Ok,

First, my english maybe have some accent because I'm from south america and I'm not used to write in english very often.

About the topic, I'm trying to restore one engine from two 6.2L 379CI Diesel incomplete engines. One '83 and the other '89.

One cylinder head is sane, but the other three must be repair.

Now I just realice that two of my four cylinder head have different exhaust valve seat diameter (intake valve seat are the same). Is it possible?... How can I know which ones are standard?

Thanks in advance.

Measure with dial calipers or Micrometer for exact valve MM. .Do not use large valve(s)/heads GM changed production to all small valves to prevent cracking between the valves . Heads crack = Baaaaaaaad!!

Back on topic fellas!

83 head would have coarse thread injector holes

83 head would have coarse thread injector holes

82 is course, 83+ were fine thread