Head Gasket Trouble - Pull Engine

Just ordered my head porting kit. Also went to the auto parts store and grabbed some permatex valve lapping compound. Ready to grind me some iron!

I figure I'm not going to need dykem very often so instead of using that for scribing my gaskets i'm going to use some pvc purple. Why not eh, got that lying around already.

Made some progress this weekend despite the cold weather. Setup a propane heater and went to town with my head porting kit and piles and piles of research I sucked up over the past month.

I started on the combustion chambers. Laid down a little spray paint, installed a couple dowel pins, laid down my gasket and scribe'd the inside of gasket. The passenger side head(cylinders 5-8) had more material from the casting than the driver side head. I used a carbide bit to slowly remove the material up to my scribe marks.

Passenger side cylinder head, just scribe'd my gasket.



This is a side by side comparison of 1 done and 1 not. Can't really tell too much with the angle but you get the picture...





Intake side of head. Same thing, scribe'd inside my gaskets. I'm using Felpro intake and exhaust gaskets. On the Ford 302 stock heads you can't just grab your intake bolts and screw down the gasket to hold it in place while you scribe. I ended up putting the head gaskets on first then hooking the intake gaskets over the tabs of the head gasket just like you would do during the installation process. Worked out just fine just a little tricky making sure they simulated the position when bolted down.

Intake holes scribe'd.



Here are a few pics after running the sanding stone to remove material to my scribe.







Now we move on to the exhaust side. The exhaust ports had a lot of material to remove. Those things were horrible coming out of the cast mold from factory. I should get a lot better flow out of these.

Here is my scribe on the factory opening. Picture doesn't show it justice, trust me there was a ton of material on the inside, more on that later.




Here is a good shot of the scribe line and also a better look at the inside of the port opening. Notice the 2 humps inside. The first one closest to the top is a hole, not sure what it's function is but it goes nowhere, just dead ends into the head. The second hump lower in the hole is of course the valve guide. Notice how ugly the walls are inside and also notice how much the airflow is restricted due to the opening size?




Here is how much that can be improved!




This shot sux but it shows the difference in the outside port size opening.




Here is a close up of before and after, notice the upper material that I was able to remove.

Before:



After:





I still haven't gotten to sanding and polish yet, only stone removal. The intake ports are pretty well done, they need to stay rough to the touch to help promote good fuel atomization. The port kit I bought however polish bits/pads are too large, they don't fit in the dam holes even after all the material I removed. They seem tiny compared to whatever the kit was modeled after... I will figure something out though.


Another process I did was clean up my water jacket ports. They were pretty bad. I also found some huge casting material left over after they were cast from factory. I didn't spend too much time on them but should get better cooling now with less blockage in those port openings.

Here is a pic of water jacket/port opening. You can see that massive mound of cast iron on the bottom of the port just inside the opening. I actually had half of it gone before I thought about taking a picture but you get the idea.




Sorry, I was pretty cold and tired after I was done and didn't take pics after I finished the water port. I spent about 8 hours on these things so far and I'm still not done... Very close though. I just took my time so I didn't screw up...

I still have to finish polishing the heads up in the exhaust ports and sand and polish in the exhaust side combustion chambers. Then I will port match my lower intake manifold as well. I will post back when its all done.

Whew...

I was reading this book by David Vizard. Starts on page 155, just read the part on "Supercharger Heads". Only a couple paragraphs.

How to Build and Modify Chevrolet Small-Block V-8 Cylinder Heads - David Vizard - Google Books


I'm running about 6psi with my vortech and this is what led me to deshrouding my combustion chamber. Is this wrong? Let me know if you can't see the online book.

I'm starting to worry now. After reading a few articles on his site I fear the worst... I may be in the market for new heads after this...

That makes me feel a lot better tmoss, thanks for taking the time to look at my situation. Very much appreciated. I will take your advise and proceed.

On the exhaust ports, what is that big bulge on the top with the extra hole going nowhere? I read somewhere it was to inject air into the mold during casting but they didn't mention there was a hole in it after they were done?? Is it ok to just grind that down over the hole? Fill the hole after grind? I will read your articles and look for this in them.

Sweet, that's what I needed guys thanks! Now tonight I will be reading tmoss articles till my eyes cross.

What about cc volume consistency? With the material I removed I'm sure I didn't get them all the same as I didn't have one of those handy dandy volume cc kits.