My micrometer only measures to .0005 so that's how I rounded the numbers in my chart. I could not use any algebraic forumulas to create this chart because my micrometer readings were not accurate enough.

Even so, I was able to create a chart that's more than accurate enough to give .0001 readings. Keep in mind, this is for green plastigauge which is the color you will need for a honda motor.

BEARING CLEARANCE.............PLASTIGAUGE CRUSH WIDTH

.0010------------------------------------------.1685
.0011------------------------------------------.161
.0012------------------------------------------.153
.0013------------------------------------------.1455
.0014------------------------------------------.1375
.0015------------------------------------------.130
.0016------------------------------------------.1235
.0017------------------------------------------.117
.0018------------------------------------------.111
.0019------------------------------------------.1045
.0020------------------------------------------.098
.0021------------------------------------------.095
.0022------------------------------------------.0915
.0023------------------------------------------.0885
.0024------------------------------------------.085
.0025------------------------------------------.082
.0026------------------------------------------.0785
.0027------------------------------------------.0755
.0028------------------------------------------.072
.0029------------------------------------------.069
.0030------------------------------------------.0655


I am confident in these numbers. There isn't too much thinking involved - I just took the difference between each pair of measurements and found an average crush-width change per graduation.

Please chime in if you feel that I made a mistake somewhere. The last thing I want is someone ruining an engine because I made a typo. Keep in mind, if any of you have made your own micrometer readings off of the plastigauge ruler, it doesn't matter is they are not the same as mine; seemingly large differences in the plastigauge ruler measurements equate to almost zero change when the bearing clearance is calculated.

 

Isn't this the same info that's supplied on a plastigauge package?

 

If it was, would I really have wasted my time making that chart?

 

Enzo, your a life saver. My only question is how do you accurately measure the width of the crushed plastigauge? Ive been using my caliper and its almost as hard as eyeballing it in the first place.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Muckman &raquo;</TD></TR><TR><TD CLASS="quote">Enzo, your a life saver. My only question is how do you accurately measure the width of the crushed plastigauge? Ive been using my caliper and its almost as hard as eyeballing it in the first place.</TD></TR></TABLE>

you are supposed to use the plastigauge strip to measure the thickness of the crushed plastiguage......i don't know why you would want to use a mic to measure it......that would be extremely difficult.

plus the plastigauge is not meant to be THAT accurate...it can never replace proper mic's and dial bore gauges.

 

If you have mikes that accurate, just measure the crank, rod or block housing, and the bearing thickness and do it right.

 

Wow, I didn't realize that people had dug up this thread and crapped on it

For the record, I spent at least 12 hours gathering the data in the first post. The only tool I used was a digital caliper, but I took hundreds of measurements and took dozens of variables into account before coming up with the averages I posted.

And for any of the critics - I used these specs to order bearings and build my current motor, which has been enduring 25psi and 8500 rpms for two years now. Furthermore, I had a full Mitutoyo mic set when I made this post, but I chose to use the plastigage instead.

Anyone who sees the word "plastigauge" and instantly starts spewing bullshit about mics and bore gauges can go jump off a cliff. If I had a justifiable use for my mics/gauges, I wouldn't have dumped them on ebay . Plastigauge is all I use now.

 

measure the inside of the engine and you get the right measurment??????

 

the post you answered is over 3 years old