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Published 2021

Stroker Crank Options

There has been much discussion regarding what crank to use for a stroker build. Several options come to mind.

  • Option 1 A 2 liter crank with the nose cut off and re-keyed for the 1600 pulley. This makes the crank useless as a 2 liter crank as there is no going back.
  • Option 2 A 2 liter crank with the nose left alone and using a spacer to fill the extra space that you would have removed with option 1. The spacer can either be a machined piece or a machined old 1600 crank pulley. The crank will need to be machined for a new key-way to accept the 1600 pulley. This method allows one to reuse the crank as a 2 liter crank should the need arise.
  • Option 3 An H20 crank is pretty much a direct drop-in with no machining required.
  • Option 4 A 1500 crank with 1600 rods and Std Toyota 5R 89 mm pistons and rings. Pistons need machined to correct deck height. G15 cranks are very hard to come by these days. Options 1-3 are your best bet.

From a discussion on the forum by JT68

To clarify:

The first strokers were built in the 80’s at least, maybe earlier, so the “verdict” has been in for decades on this tech and methodology.

The U20 crank modification is a simple operation, but it requires precision. Anyone building a stroker needs to understand that before starting on it. Like I said, you get one shot at it, there are no do-overs on this particular machine work (once you cut the crank, you can’t undo it). That is simply good advice.

The crankshaft key-way has to be relocated to drive the 1600 sprocket exactly like the 1600 crank- you simply copy the 1600 nose by moving the wood-ruff key or by using metric key-stock.

And then you correct the U20 crank nose-length issue using either method.

Conceptually it is simple but it requires exactly the same accuracy as any other critical crankshaft or camshaft machine work. I can tell you how replace a valve seat too, but that doesn't mean the average roadster owner should attempt that in their garage either. Again that is good advice.

The crank operation is a few hours of setup and fixturing, measuring and 5 minutes of (very careful) cutting. The nose issue is more time and machine work after that, so it takes time.