Thread: 355 build HP and Torque?

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Thanks for the input Pat. Regarding the head and block surface, I was thinking the same thing, especially if I end up using a shim gasket and need the smoother surfaces for a better seal.

Today I mocked up a piston and rod and measured the gap between the top of piston and block deck on each corner. Using a straight edge and feeler gauge I took measurements on both sides of the piston inline with the wrist pin. I was able to rock the piston a little in the bore in line with the pin, so I took both minimum and maximum readings at each point. The averages are:
#1 - 0.023
#7 - 0.025
#2 - 0.024
#8 - 0.027
I guess my next step is to determine how much decking I need to do if any and coordinate that with various gasket thicknesses to obtain an ideal quench of 0.040. I'm guessing by looking at these measurements, I won't be able to use a 0.015 shim and still have room to clean up the surfaces, as I would need to be 0.025 in the hole to do that and some corners are already less then that. On the other hand, maybe these measurements are already close enough to work with. We will see.

I'm thinking of taking this information back to the shop and consulting with them as what combination of decking and gasket they suggest. I was thinking I wanted to cut as little material off as I could and he already has some good ideas on what gaskets he would use.

Here's a pic showing how I did the measurements:


I also mocked up the cam and a lifter to see how it fit a dogbone and to determine how much if any machining I need to do to the dogbone seating surface. The dogbone almost sits square except it is held up a bit on the back edge. My plan is to use my own milling machine, buy a bit long enough to reach and to touch up the surface a little and remove enough material on the back edge to get the dogbones to sit square and flat.

Here's a few pics which show it in the lower and upper cam limit positions: