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Discussion Starter #1
This is my how to on removing the casting mark edges on the intake and exhaust ports. It'll help the flow some but a good valve job will help you feel the real benifits from this. N/E how this is how I do it. If n/e one has some additional info to add feel free to.

Here's what you'll need to do this:

Intake Manifold Gasket
Magic Marker (any color that stands out)
Dremel or similar tool for grinding
Carbide Bit ( I just use the coarse sanding drums)


Step 1: Clean off the intake and exhaust flange surface on the cylinder head.



Step 2: Install gasket onto studs



Step 3: Once the gasket is secured in place take the marker and trace where there is still metal showing within the ports.



Step 4: Once you have marked the ports, it should look something like this.



Step 5: Take your Dremel or whatever tool you are using and start removing the material inside the port until you have ground away the material that was marked.






Here is what it should look like once you are done. I only had enough sanding drums for 3 ports so I'll post up the completed intake side once I am done. After my friend drops off the intake plenum I'll also add how to port match the IM to the head and the TB to the IM. It's basically the same as this but there are a few differences.

I hope this helps. If ya'll have any questions or comments feel free to chime in. This covers most of it but to see the full gains, I recommend getting a valve job and oversized valves. You also should not go too crazy w/ the porting otherwise the intake charge will lose velocity. :)
 

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Discussion Starter #4
^^^^^ Nice work. I would have done a little bit more on mine as well but I didn't feel like taking the valves out and don't like chancing the loss of intake velocity. I suppose it wouldn't matter too much anyway though. I am boosting it.
 

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Discussion Starter #6
MustardCat said:
Heres from me doing mine:




I would do it on the manifold too.
BTW, what kind of bit were you using? I like the roughness it made since if the intake ports are too smooth, you'll lose atomization of the fuel/air mixture.
 

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Memento Mori
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I would highly recommend anyone doing this or thinking of doing this understand several things... #1 being if you do this to the head at all it is VERY important to have the head disassembled and hottanked... When shaving get into the valve guides problems often occur.. Sometimes immedietely and others down the road... Its just a smart idea to get the motor cleaned up after doing something that would destroy a motor in a heartbeat if those shavings entered the head or bent the valves or even wedged them... Food for thought....

Also, for a self porting job... I liek what your doing... For best gains it is crucial to knife edge where the two ports come together and try to make the size of the port consistent and as ROUND as possible... Air flows better in round tubes than oval... It also flow better when velocity and instantaneous area are most consistent...
 
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