LUNATI 60403LK - 494/513

If the engine is in the car and if the valve guides have not been machined for aftermarket guide seals you may have retainer to guide clearance issues. You should check to be sure how much clearance you have before deciding on the lift. A typical max people use is 0.500 lift for stock guides. Always best to check and not rely on these general rules. If you are rebuilding the engine and heads are off then you can have the machine work done if needed.