Simple 3rz question, finding nothing but complicated, incomplete answers for.

First off, this is my very first post & I can’t believe how long I’ve been reading all these forums to finally register as a member for the first time anywhere, real excited to join the group. I’ll get right to it though. I bought a 2001 regular cab base model, manual 4x4 Tacoma 3rz when my 2wd automatic s10 was hit head on & totaled & I couldn’t be happier with my purchase but although she runs like a dream, she did come with 210k miles. I’ve done all the maintenance, changed all the fluids, replaced the belts, filters, spark plugs & everything so that I’ve got a nice fresh starting point. I have no reason to expect an issue but I like to plan ahead & bought a 3rz with a bad head gasket for cheap to build the shit out of, (insert boost) so that when my tired original engine gives up, I’ll be prepared for a rather quick swap & be back on the road better than ever. Problem is that I was too excited to get started & didn’t really know what I was buying. I ended up with an older 3rz with the 8 port intake while my 01 truck has the 4 port, & the coil packs & all that. My question though is about the short block & what heads fit on it among other things. I want the swap to go easily as possible, so I want to know if there’s any differences between 3rz blocks through the years? Can I build the older block & then when the time comes, just swap over my 2001 head & intake manifold & electrical to basically keep it all 2001, or are there problems I’ll run into doing that? I’m also thinking turbo, but may go the supercharger route, so there’s a lot more stuff to consider head & intakewise, but for now, can I start rebuilding/building up this block? Or are there some differences? Also the engine is in great shape, we’ve taken it apart, cleaned it up, measured everything, removed the balance shafts, it’s time to start buying stuff & I just wanna make sure I’ve got the right block before I start dumping money into it. Thanks for the help & I’m sure this is probably an easy question for you guys, but everywhere I search all anyone wants to talk about is the damn ports & ecu’s & distributors & cam sensors, which I’m not all that concerned with since I’m gonna have all that stuff from my current engine.

 

Welcome to the forum! Not sure if you got your answer yet or not, but I'll try with a reply.

I've researched this motor a fair bit but am no means an expert. I did a head replacement in the past and am now sourcing a used 3RZ options to replace a motor in another truck. From my research, the difference between 8 port and 4 port 3RZ's are isolated to the top end (head, injectors, ignition and ECU) and that there are no differences in the block/bottom end from year to year.

Differences I have listed (older pre-2000 vs. newer 2000+ listed respectively):
-2 coil pack with wires vs. 4 coil pack on top of each spark plug (there's still a punch-able casting in the head to accommodate a distributor so one more iteration on the oldest models I assume)
-8 port vs. 4 port intake
-mini-header vs. cast iron manifold
-brown top 300cc injector vs. pink top 315cc
-Different ECU's to manage different ignitions
-some differences in throttle body (plastic parts used in newer models)

So between both motors, you've got the best of both worlds. Nothing I see says anything between differences in the block/bottom end. Some JDM 3RZ's had different brackets for accessories (alternator, A/C pump, etc) but all of that is swapable from motor to motor.

Good luck!