[locoteen16]

hey there every one, i just got a quick question about my 351w, i was wondering if anyone knows about how much lift i can use before my valves would collide with my pistons , i have stock dish notched pistons.

if thats too vague of a question, let me know and i'll be more specific

[The Greek]

This depends on the size of the valves, combustion chamber size, the amount that the valve springs can compress before they coil bind and the amount of travel that the valve stems see before the spring retainer contacts the valve seals and the thickness of the head gaskets.

You are getting close to the limit when valve lift starts going over .500". My estimation would be .530" of lift on the larger of the two valves, the intake. This would be with the stock, large combustion chamber heads that are usually about 69cc. Always do a mock up and check for valve clearance using the modeling clay method regardless of the advice given. Use an old head gasket that has already been compressed when doing the mock up.

Give a call to Ford Racing's "Tech Hot Line" (586)468-1356 and see what they have to say.