This is topic (PTV) piston to valve clearance in forum Tech Talk at Northern California Ford Owners  .


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Posted by 1fastmach1 (Member # 10137) on :
 
just got my new heads came with 2.110 valves so i clayed the pistons with playdoe and set my valve lash at 0 and rotated motor over and checked had .094 on the intake and .086 on the exhuast is that good or need more clearance its a sbf windsor solid roller
 
Posted by wilit (Member # 3367) on :
 
You generally want a minimum clearance of .080" on the intake and .100" on the exhaust. Some cam manufacturers say .100" on the intake and .125" on the exhaust. Either way, your exhaust side looks a little tight. You could either use a notching tool like this, or if you're running 1.7 ratio rockers, you could drop down to 1.6's.

You might be able to advance the cam to gain clearance. Advancing the cam will increase your exhaust clearance but decrease your intake clearance. Normally 1 degree will gain you .010" of clearance. So in your case you could get your intake to .084" and exhaust to .096". That'd be close, but finding a timing set that will advance or retard in 1 degree increments is going to be expensive. Most timing sets advance or retard in 2 or 4 degree increments.
 
Posted by [SHO]TIME (Member # 8962) on :
 
did you have your head torqued on with a gasket installed when you took those measurements?
 
Posted by 1fastmach1 (Member # 10137) on :
 
yes head was torqued down and already running 1.6 ratio rockers so thoose specs are to tight you think changing head gasket thickness hould work also right

[ 2016-10-18, 12:42 PM: Message edited by: 1fastmach1 ]
 
Posted by wilit (Member # 3367) on :
 
You can stack an MLS gasket to get some extra clearance, but it's not something I personally would do. The extra .020" you'd need will lower your compression ratio. Not by a lot, but for example, if you had a 9.3:1 with a .039" gasket, you'd bump down to an 8.9:1 with a .059" gasket. More importantly though, you create a greater chance of blowing out the head gasket.
 
Posted by 1fastmach1 (Member # 10137) on :
 
ok well used a .043 mls head gasket from fel pro and now have .100 on the intake and .090 on the exhuast think that will work any thoughts or still to tight have brand new valve springs and will change every off season
 




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