I tried putting at DTC using a dial indicator in the center of piston and then using a feeler gauge under the edge of a small strait edge but I get different readings all over due to piston rock in the bore. Whats the best accurate way? I am trying to figure compression height.
Thanks

 

Anyone???

 

With the crank set at TDC, lay the straight edge on the block surface 90* to the wrist pin and manually rock the piston to make both sides of the piston have equal height under the straight edge. Then, without moving the piston, move the straight edge directly above and parallel to the wrist pin. Check the gap without moving the piston.

To measure the actual compression "height", use a dial caliper between a straight edge layed on the top of the block and the center of the piston. Run the piston thru one cycle to get the reading.