I have heard of the clay process but I have never seen it done or even know where to get the clay. My situation is as follows. I have a 6.0 LQ9 with flat tops fully torn apart. I am wanting to put it together in a few weeks but I am concerned about my piston to valve clearance. The cam I am installing is a 230/236 .591/.601 @110lsa. The heads are Patriot stage 2 LS6 64cc chamber heads with 2.02/1.575 valves. I will be using the OEM 6.0 head gaskets. My questions are how do I check the piston to valve clearance with the clay? Where do I get the clay? Do I use old bolts and gaskets as not to ruin a new set? How is the clay measured? What is considered safe? If I have to have valve relief’s cut how much does it cost on average? Or does anyone know where I can buy forged 4" bore stock stroke flat top pistons with valve reliefs in them. Sorry for all the questions I just want to make sure its done right.

 

Go To Walmart And Get Reg. Clay Put It On Top Piston Do 2 Diff. Cyc. U Can Use Old Gasket R No Gasket.if U Check It With Out A Gasket And Get A Close Reading U Know It Will Work With Gasket.set Up Motor And Then Rota Motor Onceand Pull Apart.check The Caly In The Thinest Place.u Need A Dail Indercator To Read The Clay After If I Were To Guess U Will Be Around .0060 Piston To Valve Clearance.i Have .0110 Ths. With My Set Up.i Don't Of Anyone That Cut Releif In Piston But Thunder Sell Piston.

 

It's just plain old clay you find in the toy department like children play with. Just form a patch on top of one piston in the area of the valves about .100" thick and fill the valve reliefs. Rotate the engine two turns with the head on and the valves adjusted. Remove the head, slice the clay in half where the valves touched and meassure the cross section. This will be your clearance. If your cam is hyd. you will need two solid lifters for checking this. You can make some by taking two old lifters and shim them inside.

 

what is considered safe on the clearance?

 

I like at least .100" clearance with the head gasket on. I think that is what litreddevil is saying, he just got his decimal in the wrong place.

 

YES U R RIGHT BUT WITH HYD. LIFTERS U CAN GO AS LOW AS 60 THS JUST DON'T FREE REV IT PASS 5K.AND DON'T GO OVER 5500 IN THE BOX.YOU WILL BE FINE.I HAVE SEEN SOME MOTORS WITH JUST 40 THS AND THEY HAVE 500 PASSES ON THEM

 

I am planing on pushing my motor to 65-6800 range. Will I be able to do this if I only have .060 Piston To Valve Clearance

 

Yes We R Turnning Them 8200 With .040 Of P2v Clearance.u Just Don't Want To Free Wheel The Motor To High.that Is All.

 

I see, I will try the clay trick. I also may consinder just changing pistons.

 

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