help with 73.5 CIS deck height

[rockreid]

I am following Wayne's book and researching other advice on this forum but am now confused. I am continuing my rebuild of a 73.5 Targa 2.4T (CIS) stock engine that the previous owner had disassembled completely and handed over to me in cardboard boxes.

The previous owner has the case bored 0.25mm but evidently did not have the outside of the case touched. I am using 0.25 oversize bearings on the crank and it seems to turn well with no problem. The heads were rebuilt with new valves but do not know if they were fly cut. The combustion area is polished so it may be a possibility. What is throwing me is that the mating surface of the heads to the cylinder still appears to have ring residue of combustion indicating they haven't been touched.

I am at the stage of trying to determine deck height and use both the vernier caliper and squish solder methods. This is where I am confused. The stock CIS pistons have a thin flat area towards the front edge area of cyl #1 under part of the Exhaust valve. This is where I am placing the measuring devices. With the Venier caliper I get a measurement of only 0.71mm deck height from the top of the piston edge to the top of the cylinder wall. Wayne's book calls for at least 1.25mm.

Using the solder method (3.2mm acid core), I get no squish on this piston edge whatsoever using the stock 0.25mm cylinder shim. And another piece of solder placed on the domed area on the opposite side halfway up the dome away from any valves gets squished to 1.95mm.

Should I continue with the build or order shims to correct the deck height to 1.25-1.50 spec? I was thinking the case bore shouldn't affect the piston height at all. And the fact that the solder at the edge of the piston wasn't touched at all indicates I have no problem with collision between piston and valve, correct?

[E Sully]

Try this article. Gives a good procedure and where to place solder.
"Competition Engineering - Easy Deck Height"