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P400 head different than others... pics

sctrailrider said:
I agree with ferm BUT I hate electronics... yea it will never be a dmax but a dmax will not be manual pump I doubt.... but someone will do it sooner or later just not me...
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A mechanically injected DURAMAX is OLD news. Heres 2 of them, and yes, these are the same guys who did the 6.5L with twin DB's.

There was also the CUMMINS KILLER I which was mechanical injected, but they went back to electronic controls to make more HP. You might not like electronics, but they don't fail often, and they DO make MORE HP.
 
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I love that.

One time there was a guy here asking if a Ford DB2 could be run on a 6.5. Because it turns opposite of ours I told him to run it on a jack shaft. I think thats exactly what they did in the Dmax vid.
 
Burning oil said:
I love that.

One time there was a guy here asking if a Ford DB2 could be run on a 6.5. Because it turns opposite of ours I told him to run it on a jack shaft. I think thats exactly what they did in the Dmax vid.
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You should have told him he could only run it in Australia and the Southern Hemisphere because everything rotates backwards down there because of the Coriolis Effect!:hilarious:
 
A little more info..

I checked valve depth from the head surface on a new 6.5 head with the p valves and vice virsa the valves that were in the 6.5 head in the p head...

standard valve & standard head = .039" in .037" ex

p valve in p head head = .025" in .026" ex


What I found with these 2 heads was the P head valves are around .010" closer to the head surface..

While in most cases this won't make a difference but in my case where I'll be using 1.7 rockers it "could" cause trouble if not checked and accounted for...
 
I was thinking that, just wanted to make sure you got the correct spacers? They will bind if not.
 
I'll fit them as needed, I have access to several surface grinders & machine shop equipment...

Fitted my other set also, I never would have thought anyone would just bolt them down without checking them but it happens I guess...
 
Actually that "should be" one of those things that bolt on the first time correctly. Unless you put them on without valve springs I don't think you would ever know. Ive never heard of it being an issue before. If the instructions say to check it then OK, but even HS admitted fault, stood up and fixed the ones needing fixing.
 
I think they should be with in tolerance to be just bolt in and go. I get the idea of a trim and fine honing the the best possible fit, but for the average guy-a "bolt on" part.

I was wondering if anyone has put 50,000 on a set yet. If so any chattering on the roller or value tip?
 
You may right about it SHOULD be bolt & go, but sometimes things don't work that way, I did fit them without push rods first and found a little tight so I fixed it, doesn't matter as long as they don't bind is the main thing right... Personally I tend to check everything I can..

Will, I have talked to the owner of my last build, he hasn't had a reason to remove the covers but says the motor is smooth as silk and still quite & strong, didn't ask the mileage but he drives it daily.. My machinist is the one that checked the ratio after I received them and confirmed the ratio ( yes I had that checked also ) and also stated they would be much stronger than stock and thought they were well designed....
 
Alrighty then, I guess it's time for the update I promised...

First off, for those that want a for sure answer.... yes, the P400 head is a NEW engineered & molded casting...

I did cut a P400 head apart just as I did with a couple GM stock heads and as expected they are NOT the same inside, complete different casting molds used, head has been re-engineered on the inside and flaws were removed, new molds made... (very costly)

Lets refresh the differences I have confirmed and made public so far.....

Seats under both valves
Intake valve has thicker head area & under cut for swirl

And now finding....

Has a thicker deck
More metal/improved area under valve seat
Removed mold plug from between both valves
Added coolant flow between valves


The following is just my thoughts and mine only, are these heads worth the cost... not for everyone, but if you want a truly improved 6.x platform, big exhaust valves, etc this would be it... from the long list of things I have found with this motor in pieces tells me they/someone attempted to do it as right as could be done and keep the outside of the motor near the same, this info on the heads is only a few things I'm showing right now, their are more..

Can ya spot all the differences, as close to the same cut on each head, new vs GM



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