ChefJ

So I have never used plastigage before. I am going to pick some up from autozone and measure the cam journal clearance. My question is once I take the plastigage reading what do I compare it to? the other journals, or is there a value that it needs to be within?

RacerXI

Camshaft to holder oil clearance is 0.002-0.004in
Service limit is 0.006in

That's directly from the helms manual.
You should get plastigauge (looks like dental floss) as well as a strip of paper with measurements on it. When you torque it, you can use your measuring paper to determine the width. Then you can compare it to the value above.

ChefJ

so when you torque down the plastigae what we are basically measuring is the thickness? thats an awfully small amount to measure with just your eyes.

ChefJ

alright after doing some searching. You pretty much have a set amount of the plastigage, then you put it somewhere near the middle of the journal, torque the caps to spec, and then measure the squeezed plastigage to the specified chart that they give you. Should be fairly easy I guess.

Artisan7471

Its pretty easy to do, however its a little more difficult to opticaly compare it to the refrence strip and get a exact value.

ChefJ

I'll probably do the same journal 2 or 3 times to make sure that there is a decent average. Just want to rule it out or in as a problem for my oil pressure.

RacerXI

Once you do it, it makes a lot more sense than the explanation.

SpitfireS

What are you going to do when it's out of spec?

ChefJ

when or if? I'll replace what needs to be replaced. Follow the helms, could be the top or bottom cap or the cams themselves.

wadzii

if you have a decent machine shop they can line hone the cam caps to get them back in spec.

do you have OE cams?