What is everybody doing to check piston/valve clearance

[Fiatdude]

Was looking for my old stash of clay and finally found it all dried up and worthless...... Is there a newer, tricker way to check clearance????

If not where do I find a replacement quantity of clay, and what type of clay are you using?????

Enquiring minds want to know,,,,,, LMAO

[FJCamper]

Hi Fiatdude,

Regular modeling clay is available from Amazon Toys & Games, and AutoZone, O'Relliy's, and Advance all advertise that they sell Plastigage.

I favor plain old modeling clay for piston clearances.

FJC

[The Newf]

Plumbers mastic works well too.

[Fiatdude]

It was recommended to me to pull the springs off the valve and using a dial indicator, measure the distance between all the way closed to where it hits the piston.... thought I'd try this and see how it works

[sideshow]

Well all the hip kids are using candy, something like starburst or tootsie roll.

I don't run radical enough cams to need this but if I understand correctly one keeps it inside a pants pocket to warm it to very pliable, then crush it in the cylinder, cool it in the fridge(optional), slice and measure the low sport, eat the spoils of measurement.

[Ol'fogasaurus]

It was recommended to me to pull the springs off the valve and using a dial indicator, measure the distance between all the way closed to where it hits the piston.... thought I'd try this and see how it works

As a variation to this there are soft springs that you can use when checking high lift rocker arms to get valve clearan. Clay is the. List common thing I have seen and heard being used.

I also don't use use the aggressive so for what is worth.

[FJCamper]

Hi Fog,

Clay is for when you want to see, not calculate, the physical clearances.

We run an aggressive wedge-top piston design, not a flatop, in one of our engines, and to allow us to clearance the combustion chambers, clay was the only way we could do it.

FJC

PS: I like Sideshow's suggestion, but if I gave mt guys cookie dough or whatever for assembly help, they'd just eat it.

[Ol'fogasaurus]

Yes, I know that is the thing; but just to check things out you can still check clearance at full valve opening via the rocker arms (especially if it is a high lift and/or long duration cam) on intake and exhaust then hand push the valve down to see what is left and even a mike can be installed to check things out.

With after market spring just pushing the valve down doesn't give me a lot of confidence.

I've seen it done that way as well as the clay method. The last V-8 I built uses a split duration cam (Ford). Chevs tried the split duration cams for a while but ended up going back to straight up grinds the last I heard.

Anyway, it was just an idea to use or not.

[Piledriver]

Play-Doh. Comes with an airtight can and is long reusable.

Not as tasty as tootsie roll tho.