[HRDROKN]

Hey Guys,

I'm knee deep so to speak.... this will be my first multi-cylinder port job and as such I'm keeping it pretty basic! I'm thinking that I might not take the gasket match all the way to the line.... maybe a 32nd short? Just to compensate for any error on my alignment and/or any gasket expansion?

What do you all experts think?

:beer

 

[JakeDiesel]

not an expert but is lookin good to me

 

[HRDROKN]

OK... have the intake and exhaust bowls ruffed in. Not sure about these pics, but they were the best of the bunch.

Comments and suggestions....

Looking at this pic... is it safe for me to remove more material from the 7-8 o'clock are of the exhaust bowl...???

:beer

 

[Shainer]

Why not go all the way to the line? There is only a slight possibility of a slight mis-alignment creating an edge, however not opening it up enough guarantees that edge. I’ve always gone all the way unless there were structural or sealing issues. Other than that it looks good. Try setting your camera on macro focus to get better images of your bowl area.

 

[HRDROKN]

Why not go all the way to the line? There is only a slight possibility of a slight mis-alignment creating an edge, however not opening it up enough guarantees that edge. I’ve always gone all the way unless there were structural or sealing issues. Other than that it looks good. Try setting your camera on macro focus to get better images of your bowl area.

Oops.... kinda forgot about the "macro" setting!

Yes I'm going to take those ports all the way to the line... looking at the exhaust gaskets, they are held pretty solid by the manifold bolts... so I think they will be good.

:thumbsup:

 

[HRDROKN]

I re-shot these pics.... kinda figured out how my camera works!

OK... have the intake and exhaust bowls ruffed in. Not sure about these pics, but they were the best of the bunch.

Comments and suggestions....

Exhaust...

Intake....

Looking at this pic... is it safe for me to remove more material from the 7-8 o'clock are of the exhaust bowl...???

:beer

 

[HRDROKN]

Just about all done with the exhaust ports.... I still want to work the bottom of the valve guides a bit.

Comments/suggestions?

arty018:

 

[JakeDiesel]

looks good what did u use to get inside the ports. a Dremel tool?

 

[HRDROKN]

looks good what did u use to get inside the ports. a Dremel tool?

Air die grinder.... I used different long and short burrs (no stones) to remove heavy material, then used different shape/grit abrasive rolls on an extended mandrel to clean it up. I then went over the dimensions with a snap gauge to make sure that everything was dimensionally the same. Kinda time consuming as I wanted to be cautious, but the next one I'll be able to complete much faster!

:thumbsup:

 

[mathews8pt]

How much time do you have in it?

 

[HRDROKN]

How much time do you have in it?

I lost track.... but being this is my first go on a Cummins head I have been taking my time. Now that I have a good idea of how much and where... I figure I could probablly get one done in about 12 hours or so.

:thumbsup:

 

[HRDROKN]

Finally got back at it...... ruffed in the intakes today. It seems that most of the information found on porting the Cummins 12 valve revolves around the exhaust ports... not much information about the intakes?

:confused013:

 

[HRDROKN]

OK.....

The very interesting thing that I found was that the exhaust ports measured (with a snap gauge) out pretty darn even, but the intakes were off due to a shift in the casting? From the intake valve stem guide center to the bowls outer wall (as measured across the runner opening "inline with the head") progressively got tighter as measured from cylinder 1 to cylinder 6.... so not knowing how thick that outside wall area is (water jacket on other side) I evened them best I could....

Just about ready to rap up this porting job....

:thumbsup:

 

[Philip]

Nice work, looks good.

 

[hoodstack96]

So what are you doing with the intake ports? I can see how you could blend the bowls in nicely and smoth things out a bit. But last time I saw a head off, it didnt look like you could reach the #1 and #6 intake port without machining off the intake . If you found a way, or know of another approach let me know. Im pulling mine off soon.

P.s. thats a sweet porting job you got goin there !!!

 

[HRDROKN]

Ya... not really able to do much with the intake runners without cutting off the plenum. I did get about 5 inches down the runner from the bowl side though. I'll have to wait to do the rest when I get a mill set up.

Thanks for the comps.....

:thumbsup:

 

[Philip]

Its been a few months now.

You done any dyno time with the head???

 

[HRDROKN]

Its been a few months now.

You done any dyno time with the head???

:rof

I still have a couple months of work to do.... just to get her under her own power! Working on the 4-link front at this time.

 

[honestcharlie56]

and how about now??

 

[12VALVETQ]

Anything new on this thread??