how do u use a PLASTIGAUGE

 

you tear off a little piece of it, put it in the area (more than likely bearings...either main or rod) and torque the bolts down to spec. After doing that, you loosen it back up, take out the plastigauge and measure it with the indicator on the side of the original packaging....it will tell you your clearances

 

its not an actual tool.... Its a strip of what looks like dental floss and is crushable....

you put the bearings in the motor...put a small strip of plastigauge on the top of the crank journal....tighten down the crank or rod cap to the required torque....then remove the cap

you tell the bearing clearence by the amount that the strip is crushed going by a chart on the package that you compare it to ...its very simple

 

just did this yesterday, the pics are a little blurry but that should give an idea

 

http://www.c-speedracing.com/h...s.php

 

gotta love c-speedracing.com... will be doing this in a few days on a oem rebuild LS block

 

that page says torque the caps to 45 ft lbs ...which is incorrect. Ls blocks are 56 ft lbs on all of them.

Gsr will be 56 on the outside 2 caps and 49 on the 3 caps with the girdle...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by D@nnY &raquo;</TD></TR><TR><TD CLASS="quote">that page says torque the caps to 45 ft lbs ...which is incorrect. Ls blocks are 56 ft lbs on all of them.

Gsr will be 56 on the outside 2 caps and 49 on the 3 caps with the girdle...</TD></TR></TABLE>
true!

 

I know it sounds silly but DO NOT TURN THE CRANK while the plastigauge is in there.

 

You use it as dental floss before going to the local machine tool supply store to buy a set of Starrett micrometers.

 

I was talking to my buddy who builds engines for one of our race boats about me building a motor in my garage and using plastigauge. First words out of his mouth "Don't use that crap, get the right tools" I used it anyways and the motor ran hard until i decided to build it with aftermarket parts. It's not the best way but if done correctly it will get the job done.

 

haha yeah. The stuff does work, its just a halfass approach. If you don't trust the people who machined your crank and bearrings, then at least use the proper tools to verify they did their jobs properly.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Phase Change Racing &raquo;</TD></TR><TR><TD CLASS="quote">The stuff does work, its just a halfass approach. If you don't trust the people who machined your crank and bearrings, then at least use the proper tools to verify they did their jobs properly.</TD></TR></TABLE>

not really
my best friend owns a CNC machine shop and i have access to all needed tools, and presice micrometers and what not
i checked my crank down to 0.0001 of an inch

even a fresh machine part can have variation due to tool wear and error %
i checked my crank and there was about 0.0001" change between the middle and the sides of the surface
and i still used PlastiGage to check my clearances even after me measuring the inner crank girdle diameter, the crank size, and the bearings thickness
theres a reason why honda stamped the block and crank
most likely on a healthy motor, u get almost 90% of the time the right bearings by mating the codes and getting the right colors

i will always use plastigage to make sure my clearances are good
DO IT RIGHT THE FIRST TIME and the second time to make sure the first time is right

 

If a fresh part has variation due to machine wear and error %, then the machinist didn't do his job properly. I don't pay people to machine things close, I pay them to machine them exactly how I tell them to.

But you are right, $hit does happen and thats why we double check everything. But when checking to see if the $10k machine was out of spec we don't use swizzle sticks and latte straws to measure tolerances... we use the same tools used to calibrate that $10k machine.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Phase Change Racing &raquo;</TD></TR><TR><TD CLASS="quote">You use it as dental floss before going to the local machine tool supply store to buy a set of Starrett micrometers. </TD></TR></TABLE>

Plasigauge has been used for years and for 99% of the applications it works fine. Having someone who may never build but a couple of motors to go and buy a $200 mic set is not really needed.

 

Yea its not to say that plastigauge doesnt work, its just not the best method. I am sure most people are content with checking it with plastigauge... hell.... at least they are checking things in the first place. That puts them ahead of the majority of the crowd right there.

 

True