was the improvement you noticed with the head done also?

 

yes i didnt put it all back together until it was done so i dont know what individual improvements there would be

 

Oakme2, velocity is not the primary source for the turbo to spool-"HEAT" grasshopper is what makes it go.!

 

Porting increases flow, will lower EGT's and will reduce boost PSI. The reduction of boost PSI is offset by flow and EGT reduction. Its volume vs. PSI.

 

i feel there is a good improvement to be had port matching the exhaust manifold. ive done several, factory casting is poor.

 

For the reasons stated above, it's not always a good idea. Gasket matching should not be confused with port matching. Gasket matching just puts a wide spot in the flow path and causes the gases to slow down at that point, it's not generally helpful. ? Gasket matching gives one a basic start. To continue into the "PORT" farther than the gasket inside. To port a head/intake/exhaust manifold requires deeper grinding. We must remember here. Hot exhaust gases expand. Cold/cool intake does not. Its all about speed on the intake side. One has to keep the incoming air velocity up. To a point with an engine that is blown OR turbo charged. There has been very little gains come from porting the intake side of a diesel head. Unless one chops the intake off of the head and install's an aftermarket. Now int/ext bowl porting is a differant story. There are gains to be had across the boards on that...One has to take into account of the engine being FORCED inducted.
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Maybe I should have qualified/clarified that before assuming everyone would understand the concept:

That looks more like what I would call "gasket-matching." May be a good idea to mate them up if the ports don't match up nicely like they rarely do before assembling these poor-quality mass-produced castings. A smooth, even wall through the port is aways better than the sharp edge of a gasket blocking the passageway.

And of course, don't remove any more material than necessary to even up the passageway, certainly not enough to change the shape of the port or compromise the integrity of the piece.

 

Like oakme2, my experience is in porting heads/manifolds, and for too many years to even think about. Unless there was a severe mismatch issue between the head and the manifold I can promise you didn't add a single CFM to the head. So, your positive results were either from correcting the mismatch or the manifold work. Maybe the area of the manifold you reworked is the known choke to the piece. If it was congrats. But, I've never seen a meaningful increase in cylinder head flow that didn't address the valve seat area and valve shape first. The remainder of the work supports the increased "appetite" of the improved seat area geometry. I'm glad you got good results. I'm always glad when a 1st gen gets stronger. I just want to restate oakeme2 and Wannadiesel's words of caution to others contemplating it. Unless you're addressing an obvious mismatch, or you're working in the known bottleneck of the system, the potential for a performance loss greatly outnumbers the likelihood for gains.

 

He is doing the exhaust side. The more flow you get on the exhaust side of a turbo diesel, you will lower EGT and boost. The lowering of the boost will also lower the drive pressure. Its all gains. Thats why I addressed the valve bowl issue. Once again, the intake side is a set variable that unless the intake is modified on a 12 valve engine via chopped off and an aftermarket added. Your not going to do any porting other than the bowls. Like you Ron, I've been doing this for way too long. Late 70's early 80's. I had to re educate myself on turbo charged diesels. After dealing with gassers for so long. good luck to the OP, and have fun....... Good luck...

 

well guys 1 thing is for sure that i had some serious gasket issues so at least i fixed them right i have no idea what im talking about when it comes to how my truck performs now right!!!!! so i dont really care what anyone says the thing spools quicker and thats all there is to it no if ands or buts so if it worked for me good for me maybe it wont work for the other guy who goes to far and now cant get a seal or whatever it may be. im not debating flow but i am definitly excited about what i did

 

On the topic of ported heads, I was going to post a link to PDR's instructions for doing it. But they seem to have moved and/or deleted it.

Anybody have the pics saved?

I recently had the chance to see a seriously ported head with milled off intake. Those things have to make a heck of a difference. It looked like a rectangle port big block chevy head.

 

yeah i have heard of that to i would like to see some pics of that it would be sweet to have!!!!!!!!!!

 

your learning....Good luck grasshopper................LOL