2ZR-FE camshaft swap

so I've decided to go for this mod. After reading the 1nz-fe Cam Swap | PriusChat thread, the mod seemed to work without any hiccups, even after 20k miles, according to @ToyotaJesus.

With the gen 3, I see no major changes that would cause any issues. They once again took one of their standard otto cycle engines, and modified the camshafts, pistons, etc, to create an Atkinson cycle engine. The only difference is they started with a larger displacement engine. Both will have a static compression ratio of 13:1, which is high, but there are a lot more factors that determine the actual dynamic compression ratio. The gen 2's with the swap seemed to have no issues with knocking.

I am still looking into the steps, but I believe I need to pull both the intake and exhaust cam out of a 2zr-fe engine, take off the valve cover, and replace the camshafts. It appears I won't even need to remove the timing chain cover. Of course, this will require premium fuel.

I have been getting some data from my car scanner app. I've got, temps, motor torque, 0-60 times, etc. Should be able to compare before and after and see what it actually changed.

Thoughts?

 

I have been looking at the Toyota parts catalog, and listed all parts identical to the 2zr FE (corolla) engine in blue, all parts that are different in red:

• Crankshaft: 1340137021
• Intake cam: 1350137030
• Exhaust cam: 1350237040
• VVT intake Cam gear: 130500T050 or 1305037040
• Piston rings: 1301137110
• Pistons: 1310137120
• Short Block assembly (bottom): 1140037140
  • Top of crankshaft sandwich (INCLUDES PISTONS, probably why this is different)
• Engine oil pan: 114200T011
  • Forms bottom of the crankshaft sandwich
• Block sub-assembly: 1141009322
• Head Gasket: 1111537061
• Head sub-assembly: 1110139725

It seems the changes to this generation Prius engine are similar to the 1zfxe. The pistons are different to increase the compression ratio, piston rings are different, new camshafts to allow for Atkinson cycle operation, and seemingly a new cylinder head. I cannot find individual part numbers for the cylinder head block. Since the VVT gears are the same, it should be fairly simple to attach the new camshaft to the existing gears.

Unlike the 2nd gen Prius, this car has VVT on the intake cam, which means the compression ratio must adjust while driving. It may even operate with a fairly high compression ratio at times from the factory.

Going to try to find some camshafts in decent condition from a junkyard and pull them next.