Datsun Roadster Parts from Rallye Enterprises, Ltd.

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CAMSHAFT SHIM INFORMATION. There is more detailed information on the various problems that can occur with the U20 head in the 1988 catalog tech insert. When an overhead cam head is surfaced on the bottom to remove warpage, and/or the top is surfaced to remove warpage so the cam doesn't have a bind on it, you end up with the camshaft closer to the crankshaft, which makes the chain loose. This also causes the valve timing to be retarded. When you have a problem on a 2000 with valves hitting pistons, it usually isn't because the valves are closer to the pistons (although that doesn't help!), it mainly is from the valves opening when they shouldn't due to the slack chain. Always check the top of the head for flatness, the camshaft should turn with two fingers without the rockers in place. Original head thickness gasket to gasket was 4.528. Measure on each side of the front cam tower to get the critical spot's figures. Raising the towers with shims, can reduce the affect of milling. Availability of different sizes changes, sometimes you have to use two sets to get what you want. These are aircraft quality parts. Price on list is for a set of 5.

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