# Valve clearance



## mjc707 (May 28, 2015)

I have 6x heads that are shaved .030 to put on my stock 389. I bought lunati voodoo cam 256/262 lift. What is the best way to figure out clearance and what is too close. Any help appreciated. Thanks


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## bigD (Jul 21, 2016)

Yeah, you definitely need to check it. 389 pistons have the valve reliefs in a slightly different location, than the 400 engines 6X heads came on. 

Some of the 6x-4 heads came on 350 engines in which the pistons had no valve reliefs at all. But some of those engines had very small cams, with less than .400 lift.

I suppose to do it right, you need to put some clay on a piston top, then rotate the engine, and measure. 

But, a simple way might be to install very light valve springs on one cylinder, and 2 solid lifters on that cylinder. Then torque the head on, with the same thickness head gasket you'll be running(or just remember to add the thickness of the gasket to your clearance). . Adjust the rockers to zero lash. Then check the valve to piston clearance, at several intervals as he piston gets close to TDC, and all the way thru TDC, as the piston starts back down, on both the compression & exhaust strokes. If at any point the clearance seems really close, you may need a dial indicator to measure it, accurately. 

There's a lot of online info about checking valve to piston clearance. 

https://www.google.com/webhp?source...-8#q=how+to+check+piston+to+valve+clearance&*


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## mjc707 (May 28, 2015)

Thanks Big D. I was trying to search but I guess the wording was wrong on my search. I had another post about cam and you recommended the voodoo. Thats what I went with. Thanks


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## mjc707 (May 28, 2015)

Got it figured out. Thanks


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