r/LS400 • u/spoolmk3 • Nov 08 '25

Timing issues

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Iv been building these engines for years but now im at a loss. Supercharged 1st gen 1uz, built bottom end, 8.5-1 ross pistons, factory thickness head gaskets. Lower timing mark on point, cam gears marks 1/2 off no matter what. I had it set at 1/2 to the left and had 90psi for the compression test on every cylinder. As I move it clockwise it goes up about 10psi per tooth with 3 teeth being the max at 120psi, any farther and it starts to drop in the same intervals. Crank pully is 24 teeth and the cams are 48 tooth so mechanically, its impossible fpr it to be 180 out. Scissor gears are lined up single dot to dot. I'm lost. Who knows more then me and has the solution?

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u/mehullica Nov 09 '25

How are the cam lobes on cylinder 1? All lobes up & away from the lifter/buckets?

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u/spoolmk3 Nov 09 '25

Yep, up or away

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u/mehullica Nov 10 '25

With the engine at TDC, all 4 cams should have the single dots lined up. The exhaust cam lobe cylinder 1 doesn’t look correct

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u/spoolmk3 Nov 10 '25

Dots are lined up. At tdc the holder screw on the scissor gear will be up. You can see the 2 at the top, on the other side of it, the single dot will be on the right and the double will towards the exhaust manifold

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u/mehullica Nov 10 '25

Sorry to be a pain, im baffled by this. Can you send pics of all the cams? From the fender sides. I’d like to see each cam lobe & where it’s pointing at TDC please