Coil on plug setup for 1UZ
As mentioned earlier in this post it is possible to set up a coil on plug for a 1UZ, however it is a lot of work. I am in the middle of doing this conversion.
The 1UZ cam covers have to be modified to accept the coils (not enough room). I am using a set of coils from a land cruiser (98) and I have had to pocket the cam covers on a mill and weld in fillers to the cutout. The later cam covers won't work because the exhaust camn drive has been moved to the front of the cam to make variable valve timing easier (1UZ had the exhaust cam drive in the middle of the cam). The ECU's mentioned arew capable of the task. I am using an EFI Technology unit. Some ECU's could be set up to run wasted spark. That means that two coils are fired from a single driver at the same time (the second spark is fired into a cylinder that is on the exhaust stroke). I have set mine ECU up with 8 drivers so that I can tune the ignition timing for each cylinder (gives more accurate control when approaching the ingnition limits of cylinders ruinning at different temps - middle versus outside). The stock engine harness will need to have extra leads run to each cylinder and the old double distributors can be removed. The plastic cover over the old high tension leads will hide most of my modifications, however, the pockets that I cut will show slightly. The front cover can be modified to run closer to the engine when the distributors are removed.
Hope this helps you make your decision...
Steve-O