To run the 20r head on a lazer block yo have to shave the deck of the head to match the deck of a 22r head. The only problem with this mod is that you will lose some compression form the open chamber on the 20r head. Try checking out
http://www.lcengineering.com .They have everything you can ever need for a 20r/22r engine.
Tech Notes: From LC Engineering
Using a 20R Head on an 85-95 22RE Block
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It is possible to run a 20R Head on an 85-95 laser block. In order to keep the cam and crank centerline consistent with an 85-95 head, you must mill the 20R head to a measurement of 3.130 (measured from the bottom of the front cam journal to the deck of the head). Remember to re-machine the oil passage back into the deck surface of the 20R head after milling to retain oil passage to the top of the motor. LC Engineering can perform this service if you prefer. Call us, then send us your head (you'll need an RGA number) or we will supply you with one built to your specifications.
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