Deck height measurements driving me crazy, Need advice Options

[stugray]

Ok, so I bought the deck height measurement tools from the group buy.
But I cannot figure out exactly how the OP intended to use the middle plate.

I have been trying to measure my deck height accurately for weeks now and I either am not doing it right, or I have a problem.

I have the EMW AA cylinders & KB Hypereutectic pistons - brand new.
I am measuring with no shims under the cyls.
I bolt the holddown tool on two cyls with pistons installed and torque to spec (24 ft-lbs)

I set TDC on the cyl I am about to measure with a mag base & dial indicator using the middle of the piston as reference.

I then set a VERY straight edge across both cylinders and clamp it down.
I then measure the top of the cylinder mating surface down to the very edge of the piston using a dial indicator/depth gauge.
I repeat the measurement at least 5 times and average the results.

I am getting measurements that vary from .022 to .032 and they can vary by up to .0067 across a single piston (front to rear). (IMG:style_emoticons/default/WTF.gif)
(measurements at the same spot are repeateable within less than .001)

When we are trying to get these deck heights to match to within a few thousandths, I cannot see how that can be done when the piston can be off by more than 5 thousandths front to rear.

Does this mean I have bent rods or misaligned wrist pin bushings?

I had the entire rotating assembly balanced, so I would hope they would have caught something bent.


I guess my next steps will be to shuffle the pistons around and see if the measurements follow the pistons.
If they dont, I might need to move rods.
Can all 4 rods be removed & replaced without splitting the case again?

Stu

[stugray]

I will go over all of the suggestions above but here are a few comments:

Bearings are all new and stock size.
All journals looked to be in great shape. (measured and inspected).
Entire rotating assy. was already balanced by local machine shop.
Top of cyls measure flat to within .001 with full head torque.
Brand new EMW cyls & flat top pistons.

This is screaming mis-matched rods or bad crank.
I hear that the high perf. crowd have their cranks "indexed" to make sure the stroke is perfectly matched.
With yeahmag's tool I might be able to remove the rods, retorque the cyls and measure to the top of the rod journals at TDC & BTC, but I would be wary of trusting that measurement unless way off....

I have another set of rods, but not sure if they are 1.8L or 2.0L (I have two engines, so spare parts could go with either after years of storage).

I think I will give EMW a call too.

Stu