Max Block and Head Machining Amount?

[81dmc]

After I had a disaster with a local shop ruining my rather nice 3.0 heads, I finally got the ugly replacement heads and block to Scroggins Machine while I was in Houston. They told me they work with DMCH as well, so they are at least qualified for the job.


So far, the block will need to be decked .0055 to allow for the .009 protrusion of my new liners. Heads will probably need milling too.

So I must ask, does anyone know just how much milling of the heads and block is too much? When does tensioner overextension and cam timing become a problem?

[dmcman73]

After I had a disaster with a local shop ruining my rather nice 3.0 heads, I finally got the ugly replacement heads and block to Scroggins Machine while I was in Houston. They told me they work with DMCH as well, so they are at least qualified for the job.


So far, the block will need to be decked .0055 to allow for the .009 protrusion of my new liners. Heads will probably need milling too.

So I must ask, does anyone know just how much milling of the heads and block is too much? When does tensioner overextension and cam timing become a problem?

Isn't the protrusion of the liners dependent on the thickness of the liner gaskets that goes between the bottom of the liner and block? The stripe color of those gaskets denote the thickness of each and they are different ones. I used the yellow striped one as I was informed those were the most common.

[81dmc]

When I had the 3.0 liners made, it seems they were about .0055 short. So with DPIs max thickness shims, I only get .0025 protrusion.

That is why the block has to be cut down.

[dmcman73]

When I had the 3.0 liners made, it seems they were about .0055 short. So with DPIs max thickness shims, I only get .0025 protrusion.

That is why the block has to be cut down.

Understood. I'm not sure what the max machining can be done but, you have to be careful as it will throw off the timing and also the timing chains. Do you have a Eagle Premiere service manual? It may say it in there.

[81dmc]

Understood. I'm not sure what the max machining can be done but, you have to be careful as it will throw off the timing and also the timing chains. Do you have a Eagle Premiere service manual? It may say it in there.

I do have it. It says that nothing is resurfaceable, but we know that we can resurface to a certain extent.

[David T]

You also must pay attention to the fitment of the intake manifold and the timing chain covers. You can't remove much without messing it all up. Typically you only take off enough to "clean up" things. More than that and you are in "uncharted territory".

[Ron]

I think the solution is to compensate with the head gasket...IIRC, Josh at DPI can hook you up if you have the specs.

FWIW, a "qualified" machine shop should know all of this.