How is the 4 Cylinder Built Better?

I've heard it said on this forum a million times that Tacoma engines, especially the 4-cyl, is "overbuilt," "designed to last a very long time," etc. In layman's terms, what is it about the 4-cyl. engine that is made to last? For instance, the 4-cyl is a cast iron block whereas the 6-cyl is aluminum. Why?

Thanks.

 

Less moving parts. Simpler engine. That’s my guess

 

No idea. Bump.

 

Cast iron tends to last longer, maybe cause it tolerates heat better? And the timing chain instead of a belt doesn’t hurt.

 

Less moving parts, chain instead of belt, less things to go wrong. Perhaps because the 3RZ-FE 2.7 is descended from the 22-RE whereas the 3.4 is not helps? maybe it just helps with the image. I certainly know my engine runs superb even after 235,000 miles. Only thing done to it was a valve cover gasket.

 

First and foremost it’s an inline engine, which is better as the cylinders are straight up and down, so less wear just by its nature, plus its primary forces are naturally balanced. And there are just less parts vs a V engine.. one head, one valve train, one timing chain, one exhaust manifold.

Second, it’s an old school design. In a lot of cases, older engines have been over engineered. Take the 4G63 engine.. most over engineered 4 cyl in history, but won’t go down that rabbit trail… Point is, today’s emissions designed engines are the exact opposite, with most components just a little under engineered.

Also, its a longitudinal engine (runs north-south) vs transverse (engine runs east-west). My personal preference is a longitudinal engine, and its easier to work on.

The 2.7l is a cast iron block, which:
- handles heat better
- handles vibrations better
- creates better bearing surfaces
- just all round stronger.

Guys are successfully boosting this engine, which tells me pistons, rods, bearings and caps have all been over engineered.

The fact it’s a timing chain vs belt says the water pump has been built better as it has to last the same life span as the chain.

Tolerances on this engine are very tight, which simply makes for a better built, more reliable engine.

As far as the head goes, I don’t think there’s any advantage in the components on the 2.7l , other than hydraulic valve lifters means less maintenance.


To directly compare this to the V6 3.5 2GR-FKS engine, no question the 2.7L will see more miles. For the reasons above, plus this new V6 was designed solely for emissions. And emissions and reliability don’t go hand in hand. This pseudo atkinson engine means nothing more than high maintenance.. 6 port injectors/ standard fuel pump, plus 6 direct injectors/ high pressure fuel pump with its own fuel control module. The intake manifold has an actuator valve (so more moving parts), and a one piece exhaust manifold/head -- always a weak point, so if it cracks your now replacing a head. Nothing about the new V6 engine adds up to long term reliability.

 

Who knows.... but I do know one thing, it's noisy

 

Well said sir. Great info, definitely saving

 

As far as performance goes- the 2TR-FE has a forged crank, and rods. The pistons are the weakest point, as they're hypereutectic and not forged. I am one of the few who has turbo'ed this motor, and it's extremely happy on 10+ psi of boost. The head is aluminum, but ARP makes a head stud kit for about $120 that you can easily swap one-by-one and give even more assistance to the head gasket. The timing chain system is far more reliable than a belt, and the water pump interval is extremely long. Many of the parts, including the fuel pressure regulator, are actually carried over from the 2JZ. This meant for me, that longevity and finding comparable replacement parts were a breeze.

The manual tranny is also damn good. The Supras had an R154 capable of about 700whp. The Tacoma 5-speed is part of this "R" family, being the R155F (F is the 4wd models)...In fact, you can bolt up an R154 right to the bellhousing of a 2TR, or vice versa. Billet gearsets drop into the R155F, as do the clutch upgrades.

There's more, but you get the idea. The 2TR is now being referred to as Toyota's 4-cyl 2J. I love my 4-banger, and now that it's boosted- I wouldn't trade it for the world.
Plus I mean, it looks like the turbo was supposed to be there!

 

Cast iron lasts longer because it's stiffer I believe.

 

dirtdigginjoe: that is a beautiful sight! Totally agree.. it looks like it should be there. Also, good info regarding the 2JZ commonality.

 

What about the 4-cyl. transmission? Is it overbuilt, too?

 

I’d love to have my RC turbo’d!

 

Besides the stock clutch being good for about 300-ish, the gears are solid. The internals for the motor are good for about 400hp. Just upgrade the clutch with one from URD and you're good to go

 

Do it! It's honestly not that hard. You can run 5psi on stock ECU/fueling for a while. Then just add a piggyback and get a solid tune!

 

Honestly, I don’t know where to begin. I.e. parts to purchase etc. I’ve looked often, albeit not very hard, but it usually ends up on a dead end.

I’ve just planned on getting the Underdog supercharger eventually. (But I secretly want a turbo more than anything).

 

To add to everything everyone else has aid. The 3RZ has a valve train set up very similar, not exactly, but close to the same type of rocker arm/shim/bucket set up used on 9000 rpm Ferarri's and it doesn't have hydraulic lifters to collapse or wear out either. The entire engine was built as an industrial engine which is why it lasts so long when used as a daily driver especially if it never tows anything. Everything inside it is forged as far as rods and crank are concerned with the exception of the hypertutectic pistons. Hypertutectic pistons are also far stronger than standard cast pistons. If it wasn't for emissions it would probably have forged pistons as well. The 3RZ is clearly designed to be revved for long periods of time while carrying or pulling a load. They even use the same engine in buses over in Japan. I don't know how but they do.

 

The pistons are not stronger than forged. They are stronger than standard cast, however. I'm guessing you meant to say cast, but just wanted to be sure.

 

Nope, you're right. I "did" mean to say cast. I'll have to edit that post.

 

Now that I did the edit anyone who reads this for the first time is gonna really be wondering just what we are talking about.