Porting Magnum Heads

[JGC403]

I have a set of Mag heads I wanted to port, and put them on the 360 for as cheap as possible. Just to see how I did.

From what I have read I don't want to open up the valve throat and I want to leave a rough surface in the intake runner to help fuel stay in suspension.

Thoughts? This is my first porting attempt, so I'm looking for some help.

Is it a good idea to polish the combustion chamber and exhaust port? I figured it will help reduce carbon build up.


This is what I started with:




Next 2 I started to blend the valve throat with the as cast port. Should I blend more?





I started to slim down the metal around the valve guide.




Polishing combustion chamber

 

[femtnmax]

look at the 318 head porting post at the top of this forum "small block tech". Also, there is an article from one of the mopar magazines about magnum head porting.
Blending the intake bowl....for street use they say the bowl diameter should be around 85-88% of intake valve diameter based on maximum valve lift. So grind down an old valve to the diameter you need, or buy a set of calipers, or make a cardboard shape of the correct diameter and maybe with an end that fits into the valve guide hole to center the cardboard.
I would say you could blend the bowl shape some more. There are alot of details...do some more internet research and many questions will be answered.

 

[Abodybomber]

A really good valve job,with a correct bowl cutter,could make this so much easier. Are you going to run the stock valve job, or get it done?

 

[dustoff440]

magnum porting templates from mopar are no longer available, maybe someone here would be willing to loan your theirs

 

[Abodybomber]

some pictures,of a beginners port attempt .Not close ,to happy. I was working it hard,and too much....

 

[femtnmax]

here is one article to study, there are many more.
http://www.moparmusclemagazine.com/techarticles/engine/mopp_0001_360_engine_head_porting/

 

[JGC403]

For now I'm just going to use stock valve job. I'm going to lap the valves and put new valve seals on( just cause I have a extra set). I'm trying to put as little money in them as possible. For now.