Most engines are designed to make a lot of power, but are never designed to used that upper power except in very short infrequent bursts. Our Toyota truck engines, especially the 4 cylinders, are designed to make near maximum power all of the time. We scoff ot the relatively low h.p. and torque, but little do we realize that many of us are using a higher percentage of that h.p. and torque just to push our heavy trucks down the road. Do we forget that when we are loaded down like a full size truck, our engines are smaller than many compact car engines and they certainly make less "maximum" power.
Toyota designed the R series to be a truck motor from the beginning and to haul 1 ton loads down speeding freeways. That meant it would be used at high rpms and under extreme loads most of the time. So, the little 4 cylinder was designed to run at high rpms, making acceptable power, while still returning good fuel economy in the days of gas shortages. That's why a little 116hp motor can push my 5300lb truck down the road at 75 mph all day long, even with 190,000 miles and not even flinch. And I still get 17 to 18 mpg to boot! While it's pushing my truck, it's making a much higher percentage of it's maximum torque/h.p. than other larger motors in the same circumstances.
How many motors can you smash the gas pedle to the floor and bounce the rev meter only 1000 rpm shy of redline for literally hours at a time, and not only not have it blow up, but have it return a reasonable gas mileage and still keep on ticking for many, many more years to come. I know mine can.
The R series deserves nothing but respect that, despite being based on a design from the early 1970s, it can do that and still provide decades of reliable service and over 300,000 or 400,000 miles and still get better mileage than most other engines of the same time period.
I have no doubt the 3.0 V-6 is a good motor and since it's Toyota it deserves a lot respect, but it still has issues that cannot be overlooked. While I miss the power, I don't miss the complexity or expense of repair or simply never knowing when my headgaskets might fail once again.
Since Toyota was in no rush to design a new line in the R series, it had plenty of time to think about designing the 3RZ. And when it did, it had perhaps the best compact truck motor ever built. The 2.7 liter delivers the best of all worlds. The exact same power and torque as the 3.0 V-6, 22Re longevity and absolute reliability and better fuel economy than both of the older motors. It's an unsung hero, because we only see it in a few base Tacomas, but it's really the ultimate Toyota compact truck engine and there's a reason why, other than the 22R/22RE series, it's one of the few motors here in the U.S. that Toyota also uses in it's very abused overseas Hilux. That's right. The 3.0 V-6 was not commonly used overseas at all.
