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ovanay elinquentday
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Discussion Starter #1
Ok, so I was curious as to what my piston deck height actually is, as I rebuild my engine following the crank bearing failure.

One of the pro's with a shop will have a more precise way to do this, but I just wanted to know things were within the norms.

Here is what I did. First I bolted on the cylinders with the pistons installed. I used some plastic pipe spacers to let me tighten down the jugs. They are not to factory spec, but they are bottomed out pretty well.


1 - Cylinder

Then using the depth gauge on the end of my caliper, I measured the height difference at 4 places around the piston perimeter.


2 - Vernier Caliper

The pic of the caliper shows it opened up quite a bit, but when I measured the deck height, I found it to be .001 or less. As close as I can measure it, it's essentially 0.0". Works for me.

Just in case anyone's interested, these are CP 10.5 pistons for a 98 build. The raised floor takes up about 7.5 cc's. The alternative would have been to deck my heads to get the CR back up where it needed to be for my new cam.


3 - Raised floor pistons
 

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Perfect, throw a .0030" head gasket and your good to go. Dont forget to check piston to valve clearances. Make sure your at TDC when checking deck height!!!!!
 

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ovanay elinquentday
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Discussion Starter #4
DEW2112 said:
Perfect, throw a .0030" head gasket and your good to go. Dont forget to check piston to valve clearances. Make sure your at TDC when checking deck height!!!!!
I was on a roll. I've got another set of pics from checking the valve clearances that I'll post later...
 

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Sounds great GPO03FatBoy. Glad to see that you're gettin'er back together, better'n ever!

VicW.
 

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Passin' through
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Pvc???

GPO03FatBoy said:
I used some plastic pipe spacers to let me tighten down the jugs. They are not to factory spec, but they are bottomed out pretty well.
I'm getting ready to follow suite. Does anybody object to using this method, simply using crappy pvc spacers to snug down the jugs? I was thinking the spec torqs should be applied to get a good reading on the deck height....
I'm all for short cuts - if they produce.
 

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Measuring Method

How you did that with verniers, is fine.
We use a depth micrometer here.
Scott
 

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Free is Good
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My 2 Cents. I have flat top pistons. I clamped the cylinders as you did. I set the piston to TDC. I used a machinist rule on its' side and used feeler gauge to measure the gap. On my front I couldn't get a gauge under it so I presume zero height. on the rear I got .00025 so effectively zero.

Lou
 

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Flashkev said:
I'm getting ready to follow suite. Does anybody object to using this method, simply using crappy pvc spacers to snug down the jugs? I was thinking the spec torqs should be applied to get a good reading on the deck height....
I'm all for short cuts - if they produce.
PVC spacers work great. You don't need to torque them down to spec to get a proper deck height measurement.

A machinist ruler and feeler gauges work as well on making the measurements.
 

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BikerLou said:
My 2 Cents. I have flat top pistons. I clamped the cylinders as you did. I set the piston to TDC. I used a machinist rule on its' side and used feeler gauge to measure the gap. On my front I couldn't get a gauge under it so I presume zero height. on the rear I got .00025 so effectively zero.

Lou
Of course, if you cannot get the feeler guages between the piston and the machinist's rule, you would want to see if you can get a feeler guage between the rule and the top of the cylinder. Just in case the piston is actually sticking up above the cylinder...negative deck height.
 

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bigbluff said:
Of course, if you cannot get the feeler guages between the piston and the machinist's rule, you would want to see if you can get a feeler guage between the rule and the top of the cylinder. Just in case the piston is actually sticking up above the cylinder...negative deck height.
You can see how it is done here ... http://www.bigboyzheadporting.com/showthread.php?t=92
 

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bigbluff said:
Of course, if you cannot get the feeler guages between the piston and the machinist's rule, you would want to see if you can get a feeler guage between the rule and the top of the cylinder. Just in case the piston is actually sticking up above the cylinder...negative deck height.
10-4 err a 1010 0100. @gree:
 

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ovanay elinquentday
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Discussion Starter #15
BikerLou said:
10-4 err a 1010 0100. @gree:
LOL!

I can just see a 21st century trucker chimin in on his CB:
And a big 1010 0100 to you too good buddy!
 

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"Honest officer! We were only riding 101011 miles an hour..."
 

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BikerLou said:
10-4 err a 1010 0100. @gree:
Just reading some older posts this morning & came across this one.

Isn't a 10-100 CB talk for taking a leak?:corn:
 

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jerry34208 said:
Just reading some older posts this morning & came across this one.

Isn't a 10-100 CB talk for taking a leak?:corn:
I believe that would be 1010/1100100 for taking a leak.
 
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