Does anyone have the specs for this on an engine with a new Stipe 250 cam and new valve seats? I do know that it's not the same as Ford's!
I believe the general thought with new cams and valves is .010-.012". Any more clearance than that is just wasting lift.
I like .0015" I like to knurl the valve guide and then ream it to one and a half thousandths.
You can take them in and have K-line bronze bushings installed by internal swaging. Then if the valves are good, have the stems re-sized and then ream the guides to fit the smaller valve stems.If not then purchase new valves.
Thanks, Seth. Frank, do you mean 0.015"? One and one-half thousandths seems kind of close.
The engine is all assembled and runs well; it's just that it has developed a lifter knock on one or two and I want to check and re-set them all.
Lang's catalog page info:
STIPE camshaft for Model T. Standard lift and duration, (stock grind .253). New Improved Cam, but with a lower ramp velocity and a smaller valve lash for quieter engine. Easy set-up. Uses stock lifters. No core required. Note: Set the valve lash at .010.
Valve lash and guide clearance are not the same thing. RV i think you mean Lash.
and....of course the valve lash is for new steel valves, not the old original Ford two piece, iron head, steel shaft valves, as those will expand.
For me, stainless steel Chev&)#&* racing swirl-headed valves work good with modern keepers and the Stipe cam!
R.V. You asked about valve guides and that is one and a half, I was answering your question about stems running in the guides.
I like to set valve lash at .010 for intake and .012 for exhaust.
I noticed that the Ford factory shop manual calls for a lash adjustment of 1/32" which is, if my math is correct, roughly .03125".
True, but Stipe suggests .012.
Yes; I meant 'lash'. Despite well knowing the correct terminology, I have always referred to "lash" as "clearance" and probably always will. Something about a 'trick' and an 'old dog.'
Dan, The Ford 351 Windsor valve is a tad larger and keep your Ford all Ford. The price is close and you get a larger valve. Scott
Would .012 be acceptable for stock valves with adjustable lifters as well?
Correction to my previous post...I'm using stainless valves, stock re-ground cam, & adjustable lifters. Any experience with tighter tolerances such as .012 for this set up?
+1 on the 351W valves!! No chebby parts!
I normally set the intakes at .010 - .012 and the exhaust closer to .015. Seems to just fine.
Question: it seems pretty universally accepted but why are the exhaust valves always given more lash?
Because they get hotter and expand more. I use 10 & 12, like many others here.
In a perfect world, there would be no lash. The valve would open the full amount of lift built into the cam. But, it's not a perfect world. As things heat up, they expand, and not everything expands the same amount. We adjust valves with a little clearance or "lash" between the lifter and the end of the valve stem so as the valve gets hot and expands, it has room to do so. If it has too little lash, when it heats and expands, it will not close all the way, resulting in low compression and burned valves. If it has too much lash, performance can suffer due the valve not opening as far or for as long as it is supposed to. Intake valves don't get as hot as exhaust valves, so they don't need as much lash. I can only assume that the material that today's valves are made of does not expand as much as whatever Henry used. Hence the smaller amount of lash today. I suppose in a realistic, but still perfect world, the lash would be EXACTLY equal to the amount the valve stem grows. But again, we don't live in a perfect world, so there will still be a frog hair's worth of lash left over even when it is up to temperature.