I purchased a set of MP cast iron heads #576 or 578 too many years ago to remember what the scoop was on them. They came w/ a 2.02 intake, pocket ported intake runner and fully ported exhaust runner. Getting ready to assemble, and I discovered that the rocker arm pedestals are taller than stock and that they were drilled and tapped for 3/8 hold down bolts. I think that these heads were cast with W-2 specs??? Does anyone know what are the dimensions for cutting down the pedestals? Are they to be cut for W-2 pedestals? Need to know what to say to the machine shop or am I missing something? Thanks

They are probably set up for the longer valves
like the long valve W-2.. if so then the pedestal
is taller and moved over... check a long valve
in them before you do any cutting on the pedestals
I dont have my books with me to tell you the valve
length on the long valve but its in the MP books..
the 3/8 hold down bolts were stock in the performance
heads

Valve is 5.29 to 5.33!!

576 is similar to a 308 head, but without the EGR hole under the intake. Make sure you check how the intake pushrod holes were drilled. I'm pretty sure they had some set up for T/A or W-2 rockers.

Any part numbers left on the boxes, if you still have the boxes?

"EGR hole under the intake" ??

I'm not following you there.

Under the exhaust ports. Fingers were typing faster than the brain was working! Was thinking about the "intake" pushrod holes.

Aaaaahhhhh....... The AIR injection holes under the exhaust

I knew it couldn't be hard to figure out even though I was getting it wrong! lol All I ever did was plug them regardless of what they were for.

Yeah those air injection holes were for emissions..
they pumped fresh air into them so it would pass
emissions

Is there any easy way to calculate how much grinding of the pedestals for aftermarket(W2)rocker stands? This is going beyond my comfort level and I would like to have some info when I call the machine shop. Thanks

I dont know if you posted a pic of your current head here, but if they have std. rocker stands, use std rockers or are your heads already cut?

Stands are taller than stock, flat surface and have been drilled and tapped for 3/8" hold down bolts.

Depending on rocker arm manufacture....some times they have specs for stand height. I know T&D have instructions with their sets that show how to measure for correct stand height. Go to their web site and look under w-2. I believe it is based off of stem height.

There is a guy on here that does rocker arm
work.. sets up the rockers for proper geometry..
his handle is something like G3.. others on here
have used him.. maybe they will chime in

Mr.P Body, your thinking of B3RE.

So is the problem that you put standard length valves and they take long valves so you are trying to modify the stands to stock. If you have not bought valves I would go long valve and save the machining.

This is a complete head package from MP. No paperwork about valve length, taller rocker stands, etc.I just bought them last of stock SB heads. Put them on the shelf w/o opening the box. Thought that I had all the parts to assemble a complete motor and this is my only stumbling block.As soon as I get my spring compressor back, I'll measure the intakes.

Whats the P/N on them... some one should be
able to tell you if its a long valve head..
I dont have my books with me so I cant help
you there... I have 2 sets of econo W-2s at
home.. one set of each.. long valve and standard
and they have different stand heights... but with
the econo heads they have the cradle cut in the
stands for the shafts.. racing version is flat..
they did build a few versions of the race heads
that had different stand heights.. one version the
stands are basically dont there.. just flat and it
uses a tall alum stand.. then some use a short stand

The casting # are really bad. Very hard to read. That's why I posted 576 or 578. I took a few pics had had one of my kids enhance the images but of no help. I'll try a strong LED light and magnifying glass. Pedestals are flat. Would some pics of the heads help or???

Not to add to the confusion but I have a set of '576' heads. Mine are 1.88 valve and the rocker stands are stock configuration with 5/16" rocker shaft hold down bolts. They are basically a 308 without the smog holes. I also have two sets of factory 308 heads from hydraulic roller motors, the pushrod holes are exactly the same as these.

Mopar was offering ported versions of these back then. They were calling them high swirl. I looked in my small bock engine book which was from the late 90s. I believe they used the 576 casting but sold them as a package under a different part number with various levels of porting, stiffer valve springs, etc.

Also looked in my 1998 MP catalog and that's even more confusing with all the different part numbers, nothing resembles exactly what you have.

Plus, I definitely don't see anything that mentions modified rocker stands.