Join Date: Dec 2012
Location: Gastonia, NC - Born & raised in Connecticut - 31 years
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CCing Heads - How To
Finally getting around to doing this. It is important to know, or have a good idea, of how many CC's your particular head's combustion chamber is. This is important when trying to figure out the big question of Compression Ratio. Pontiac advertised the combustion chamber CC's and websites will also give you that number, but those numbers are typically off and less than accurate. Then if your heads have ever been modified or cut, you could have a greater unknown as to the actual CC's of your heads. So here is a simple & inexpensive way to check and at least get pretty darn close.
Pic#1 shows the tools needed. Small Level, Food Coloring, Flat Plastic Panel, & Vaseline. The Plastic Panel is what you will place over the combustion chamber to seal it so you can fill it with a measured amount of liquid - water with food coloring added. I used an acrylic photo stand that was on sale for a couple bucks, but a piece of plexiglass would probably do the job - just don't get it too thin and flimsy. You can see it is 5" wide, so it was probably for a 5"x7" photo. The acrylic panel is pretty sturdy. I used my die grinder and cut-off wheel to cut off the base and then cut it off at the top where your photo would normally slip in. Then grind the edges smooth so it lays flat. No doubt you could use a jig saw to cut it as well.
You will need to drill 2 holes in it - I believe I used a 1/4" drill bit, but the hole size has to be a little larger than the end of the syringe you will be using. Where? I placed my panel over the combustion chamber and simply marked where I wanted the 2 holes which need to be within the combustion chamber area. I want one near a chamber edge which I will call the "top" and the lower hole to be about 3/8"-1/2" away from the chamber wall. You will be adding your water/food coloring at the hole at the "top." The other hole acts as a vent.
The Vaseline will act to seal the plate to the head surface. I suppose you could use some Vicks Vapor Rub, light axle grease, or even tooth paste (maybe?), but I use the vaseline.
The Syringe come from my local pharmacy. You will see articles that use a graduated glass burette & stand which we all used in out science classes, but why? I'm cheap and I'll never have a use for a glass burette -even when measuring the exact ingredients for an experimental alcoholic concoction. Now it may take a little convincing to get your pharmacist to give you one of these for free (because they are thinking "drug user" when they see me and my tattoos), but tell them you need it to measure the CC's of the combustion chamber on a Pontiac head so that you can calculate the needed compression ratio for pump gasoline with the ethanol in it. They won't have a clue what you just said, but it sounds scientific and not "druggy." Mine is a 12 Milliliter syringe which is the most common among drug users like me of course. 1 milliliter is equal to 1 CC for our purposes.
Pic #2 are the stands I use to hold up the head. Got these at Harbor Freight for real cheap - made in China. They are called "V-Shape Hang All" by StorHouse. Should be able to find these at a number of places as I have seen them in other stores. I drilled a hole at the top arch which a short 9/16" bolt/washer/lock washer will go through. This bolt will be used to attach them to the side of the head to act as legs. I suppose you could also use two flat pieces of bar stock, drilling matching holes at one end, which would then create a set of legs by passing your bolt through the holes and bolting to the head. The "Hang All" just seemed convenient & cheap.
Pic #3 is the combustion chamber on a 4X head I just picked up. I only cleaned one chamber. Used brake cleaner, green scuff pad, and wire brush to get it fairy clean. Make sure the head surface is nice and smooth as this is where you will lay the plastic panel. Also, do not forget to insert a spark plug to seal off the spark plug hole and it is needed to get an accurate CC reading.
Pic #4 is what the head looks like with the attached "Hang All" legs. Don't get carried away with tightening the bolts & crush the tubing. Tighten just enough to keep the head from rotating on you.