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]

Ok, got the new tools to do this right, and the results are the same:

Here is a picture of the two "rails" that hold down the cylinders (this is yeahmag's tool with AL spacers replaced with steel pipe).

(IMG:http://www.914world.com/bbs2/uploads_offsite/i366.photobucket.com-10819-1350969386.1.jpg)

Here is a pic of the flat plate that allows you to measure the edge of the cylinder, the edge of the piston (both sides and center)

(IMG:http://www.914world.com/bbs2/uploads_offsite/i366.photobucket.com-10819-1350969386.2.jpg)

Here is a pic of zeroing the depth gauge on the cylinder edge

(IMG:http://www.914world.com/bbs2/uploads_offsite/i366.photobucket.com-10819-1350969387.3.jpg)

Pic of one side piston:

(IMG:http://www.914world.com/bbs2/uploads_offsite/i366.photobucket.com-10819-1350969387.4.jpg)

And the other side of the piston:

(IMG:http://www.914world.com/bbs2/uploads_offsite/i366.photobucket.com-10819-1350969387.5.jpg)

I then flip the AL plate and repeat.
The measurements are dead on repeatable.

One side of that piston measures 0.022 and the other side 0.030.
The other cylinder measures 0.031, & 0.032 which I guess is more normal.

Stu