I've been told that in most states the "ECU year" will determine what standards they expect your truck to pass. So, if you have a 97 ECU you'll have to be OBDII. I'm not up on CA laws though.

 

That would make sense, as that allows the Smog process to identify the engine type electronically, and apply the standards for that vehicle.

 

Hey everyone im new very new to this forum and I had a few questions for all you...I just purchased a 90 runner with a blown motor. Im trying to decide if I want to go with the 3.4 swap or just stick another 3L back in it? Besides all the issues with the smog and what not is it common practice to swap the tyrannies to or will the 90 manual tyranny hold the extra power?

 

From what I've heard from most people is that the manual tranny that comes with your V6 is plenty strong for the 3.4 and it bolts right up. You have to use the 3.4 clutch though. I'm choosing to swap the 3.4 because I won't get the power as easily as if I swap the 3.4