Cylinder head modifications

[mobile_bob]

Doug:

frankly there has been volumes written on the subject of port design and redesign.

the long and short of it, is more damage to flow can be done by getting in there and grinding out without knowing specifically what and where to grind.

if there is flashing, go ahead and grind it out, if it looks like a purposely placed part of the casting i wiould hesitate removing it.

if you have port to manifold mismatch, go ahead and match em up. i would grind on the intake more though. you never know when you are going to hit water in the head port.

got any pictures of the port and this particular detail?

bob g

[Doug]

Can do Bob, some time today

Doug

[Doug]

Here Bob:

http://www.putfile.com/dougwp

[Doug]

I made a file all about the Petter project and moved everything to the new file along with a few other picture of some of the more gruesome details....

http://www.putfile.com/dougwp/images/31565

Doug

[mobile_bob]

Doug:

while that seemingly looks like an obstruction, it may well be there purposely to help swirl the intake charge of air to help scavenge the cylinder.

i would not remove it until i could document whether the original used this feature.

even so, if you figure the actual cross section under the open valve based on lift and area, you may find that this "obstruction" really does not hamper flow in either event.

bob g

[listerdiesel]

Bob:

I'd like your take on the turbulance area in the intake port of the Petteroid....

Basicaly its a ridge counter sunk under the valve seat just above the top of the runner. I've seen something like this on other DI engines but I have to wonder if this realy makes a difference or would it be better to simple grind most of it out. Does the difference in turbulance make up for the loss in VE?

Doug

For what is basically a relatively low-speed diesel, with low BMEP etc., this sort of thing in the inlet tract is not going to make a big difference with the (relatively) slow air-flow going through it.

As diesels normally work with unthrottled intakes the inlet side of things is usually fairly unsophisticated on idustrial stuff, compared with a diesel like the VW or BMW auto diesels (for example)

Peter

[Doug]

It looked to me like this was intentional and part of the design but I had to ask the experst if they thought a little smoothign and cleaning might help.
Thank you guys....

This still leaves me with a spare head that has a minor offset intake runner castign defect....

I'm kind of tempted to remove these obstructions and use this head with a modified intake as a producer gas head of I can figure out how to squeeze a spark plug into that injector port....

Doug