on those years 03-04.5 I was told there was a very small difference in the head, from the 04.5-07 years.

anyone know of this?

I have both heads in front of me, and the only thing that I can see differently is the EGR in the intake, does not look like a a casting difference.

 

EGR? I didn't think any of the common 47-state 5.9L Cummins had an EGR, and I'm not even sure the Cali-version would have had one???

I want to remember the biggest change was something to do with the valve guides, to better retain them at some point (there was a rash of failures due to the valve guide dropping and holding the valve open).

 

Thanks Steved, I am going to look into that.

 

PTC, is going to make an aftermarket head for the 03-07

we have looked at the valve guides and have noticed a that on the rockwell tester, the valve guides are stronger, I have also have been told that no one likes the seats, if we were to make the heads without seats, would that be something you all would be interested in.

give me some feed back on this, we are going to start the first casting in 6 months.

this is the time to really give me good ideas about what the high performance people want.

 

I was "told" by a guy that races his sponsored truck, that the 04.5+ heads flow much better. Don't know if its true or not.

 

The pistons and injectors are different, but I believe the head is structurally the same. Everyone I've talked with from Cummins has told me the common rail engines have no lack of exhaust movement, the marine engines are 330 and 480 HP from the factory with the same head, the intake side I'm not so sure. That doesn't mean some grinding and polishing won't help some

Cummins_guy a compressed graphite head would be awesome and/or any way to put that thing on a diet. Send me an email sboll77@yahoo.com

 

305 325 = 20

 

the heads will be in next week.

 

Anything ever come of this? Did you make a head that will flow better and have better valve seats/guides??