Porting 3b diesel head (1 Viewer)

[bj70cruzer]

Is it worth removing this ridge near the exhaust valve seat while i have the head off?

Intake side dosnt seem to bad compared to the exhaust

 

[gerg]

I removed mine in my 3B when I did some head work and it was easy and is well worth the effort.
Some of my pics are in here match porting and polishing a 12th

 

[bj70cruzer]

Thanks .

Did you notice any difference after porting it?

I removed the ridge with my die grinder and it looks much less restrictive. Rest of the port doant look to bad

 

[bj70cruzer]

Hard to tell in the picture but this is after porting

 

[gerg]

So it's a tuff thing to tell since you never do just one mod in isolation. I can't think of a reason why it wouldn't help.

 

[dare]

I've got my 3B head off now, I can't believe the ledge on the pushrod side (long turn) of the intake ports. All it's going to do is unstick all the air from the port wall and push it the wrong bloody way across the back of the valve?!

I'm smoothing out the ridges trying to leave as large of a radius as possible, knocking the dags off the ports and generally smoothing a few things out. The dags in the exhaust port are particularly nasty. I might port match the intake if I'm not sick of this by then.

Overall the 3B ports are better designed than I expected but the parts just before the valve seat are pretty WTF. Obviously I don't just happen to have a flow bench on hand but I reckon a quick tidy up is certainly going to be beneficial. You can't argue with free.

Later on I'll whack the port dimensions through pipemax. Being turbo diesel a lot of the info is irrelevant but it does give advice on port minimum cross sectional area and cam selection which is interesting.

 

[gerg]

Cool. My heads machining was pretty crude too.

 

[cruisedeisel]

Good to know. I will be doing mine when the head has to come off.

How many kms before a routine precup swap?

 

[gerg]

That is a good question....Ive never found an answer.