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Toyota 3RZ 4 Cylinder Engine Swa - 4-Wheel & Off-Road Magazine

Toyota 3RZ 4 Cylinder Engine Swap - More Turtle Power Fred Williams Brand Manager, Petersen’s 4Wheel & Off Road Photographers: Marlin Crawler 4x4 Toyota 22re 4 Cylinder Engine Horsepower toyota Tacoma Photo 18091041

Poor Clampy Has Been Parked In The Corner Of my shop for almost two years now with a busted engine, and not only have I been craving some rockcrawling in my own ride, but I've also hated having my favorite 4x4 looking so derelict. The radiator had busted while four-wheeling, and I patched it together before limping the old truck back to town. Unfortunately the patch didn't hold and by the time I made it back I had paid for it with a blown head gasket and a serious knock coming from under the hood.

Clampy's old 22RE four-cylinder engine was a great powerplant for a mini-truck. Though not a powerhouse, it was torquey and reliable, but when mixed with a blown head and a hundred-some thousand miles it was ready for some help. Of course this opened a can of worms when considering options. Should I repair the old engine or replace it with something else? If I replaced it, what would be the best option? I decided against the rebuild since I was ready for a little more power.

The truck is built around a four-cylinder with ultralow gearing, so I decided against more displacement, and with the price of fuel being so high, I liked the economy of a little motor. I also looked at a small Toyota diesel, but parts are rare in the U.S. I also wasn't sure I could make it a legal swap in California, where many of the trails are roads and require proper registration.

In the end I followed a trend where Toyota guys have been taking the slightly larger four-cylinder from a newer 4x4 Tacoma or 4Runner and swapping it into the old Clampster with help from the crew at Marlin Crawler. Owner Marlin Czajkowski is an icon in the 4x4 Toyota scene, where his work with dual transfer cases is legendary. Both he and his son are also running the 3RZ 2.7L Tacoma four-cylinder in their early-'80s mini-trucks with great results. These 16-valve engines have better cylinder-head flow rates than the 22RE, are small enough to fit in the early Toyota engine bays, and have bellhousings that bolt right up to a G or W Toyota transmission, which were found behind most 22R and 22RE early Toyota engines.

Of course many of you wouldn't dare swap in an engine with less displacement gain than a can of beer, but Clampy has always been an underdog. Clampy still may not win a drag race, but like a good turtle it will keep on plugging away.

4x4 Toyota 22re 4 Cylinder Engine Horsepower old Toyota Engine Photo 18091044

Tacomas use a few different four-cylinder engines. The two-wheel-drive models use a 2.4L version known as the 2RZ, and though it's still a step up from the 22RE with a stock 142 hp, for all the work you might as well swap in the 3RZ. The 3RZ is found in the '95-and-newer 4x4 Tacomas, 4Runners, and 2WD T-100s, and can be identified by the 3RZ set in the casting of the engine block. A good thing to remember is that 3RZs are only found in newer six-lug Toyotas (even the two-wheel-drive prerunner models), otherwise the four-cylinder is 2RZ. In some states you'll need a 4x4 version to do a legal swap, so we started with one from a 4x4 Tacoma, but the T-100 version is just as good. Also from '95 to '96 the engines use a distributor, then in the '97 they switched to two coil-ignition packs, and then in 2000 they went to four coil packs, no EGR valve, and two catalytic converters. In '06 they came out with variable valve timing. We went with the distributor engine because it is simpler to install, and when we were hunting for possible engines these were more available.

PhotosView Slideshow It was sad to see the faithful old 22RE go, but while we had everything out, Marlin's team built Clampy a new transmission, which made the hurt go away. You can read all about it in "Tuffer Toy Box" (Sept. '08), but I can tell you that the old tranny was a weak G54 from an '84-'88 carbureted truck, though it should have been a W56. A W56 is better than the G54 and about 30 percent stronger because of helical-cut gears. However we eventually swapped in an R151F from a 3.0L V-6 truck that is even stronger than a W56, and used Marlin's exclusive 3RZ to R-series transmission conversion bellhousing. The '97 3RZ 2.7L four-cylinder engine from a 4x4 Tacoma is rated at 150 hp and 177 lb-ft of torque in stock form. That's pretty good when compared to an '86 Toyota 22RE, which only put out 105 hp and 137 lb-ft. You big horsepower guys think I'm crazy for even wanting an engine with under 200 ponies, but remember we make up for these low numbers with gearing. We were able to track down this engine and a complete wiring harness from TAP recycling in Fresno, where they specialize in Toyota parts. Clampy grew up in upstate New York, where the winters are harsh and road salt preys on young Toyotas. With the engine bay empty, I was able to see all the rust and rot in the front frame. Rocky Gleason was head surgeon on this operation and his first goal was getting the engine bay and frame prepped for the new heart. Rocky reinforced the framerails with some 3/16-inch plate that also strengthened where the steering box will mount and helps tie in the new shock towers and motor mounts to a larger frame section. The engine bay also needed a wiring rehash, especially considering that this new engine would have a different computer to control it. To get the whole package together, I rounded up parts from the local Toyota Dealer. You don't need to use original Toyota parts on your swap, but I have found them to be extremely durable. This pile includes basic tune-up parts like a distributor cap, a rotor, and plug wires; engine parts like motor mounts, radiator hoses, a complete new clutch and flywheel, and a new catalytic converter to help pass smog. Even though the new transmission is 1/8 inch longer than the stock one, we kept the dual transfer cases in the current location so we could continue running the beefy Driveline Tech driveshafts. By installing the powertrain in the frame and lining up the transfer cases and tranny, we could build the motor mounts. (This photo is after the swap and shows how the exhaust was swapped to run down the passenger side.) Once the engine was centered and aligned so that nothing would interfere, Rocky made new motor mounts for the frame. These mounts utilize the factory Tacoma engine-mount bushings, but now attach to the inside and top of the frame with 1/4-inch plate and an additional 1/8-inch strap that wraps underneath and up the outside of the frame. Similar motor mounts are being considered for production at Marlin Crawler. Since Clampy has a solid front axle, we needed a different oil pan to clear it. A T-100 pan bolted right on and gave us the clearance we needed. Once the engine was in the truck, our first step was plumbing. We used two top 3RZ hoses to run from the 3RZ to the original 22RE radiator. We also installed a modified 22RE clutch fan that was refilled with Toyota silicone. Clampy came with fuel injection and has an electric fuel pump in the tank, which makes enough pressure to feed the newer engine. When it came to electrical, the 3RZ is running a new computer and a mixture of wiring. From Clampy came the wiring to feed all the gauges and lights, from the Tacoma came the wiring to run fuel injection, and a new wiring harness from Off Road Solutions connected the other two. The Off Road Solutions harness picks up the speed-sensor signal from the back of the speedometer gauge to tell the ECM what speed the vehicle is moving. All the terminal ends are labeled, sealed with heat shrink, wrapped in wire loom, and ready to plug in, plus the monster harness can be custom-ordered to include lights, horn, radio, gauges, and so on. With the engine in, Rocky installed a new set of Marlin Crawler shock hoops, and, needing shorter shocks, we ordered a set of 13-inch BBCS shocks from Poly Performance. Clampy has always run a ram-assist steering so the old 22RE pump had been modified to flow more fluid. The pump on the 3RZ may also need modification if the steering is too slow after it has been properly bled. Marlin Crawler can also supply a ram-assist steering setup for your Toyota if your tires are taxing your old box. The final step in the install was when we bolted on this AEM air filter. These dry filters don't require oiling, and the small 5-inch cone filter fits in the tight engine bay. AEM offers a version of this filter with an opening on the end for an air-temperature sending unit that the engine needs in order to run correctly, but our layout required us to drill a 1/2-inch hole at the base to fit the sensor. 4x4 Toyota 22re 4 Cylinder Engine Horsepower dyno Test Photo 18091080

Before we plucked the tired four-banger from under the hood of this off-road powerhouse, we gave it one last run-on the dyno, that is. We took Clampy over to Precision Auto and put it on the rollers to get some preswap figures. These guys specialize in high-horsepower import cars as well as torque monster diesels, but we could tell they were impressed when Clampy came wheezing and coughing into their shop. Yes, those are the tires off our trailer on the rear end; the 39-inch Krawlers wouldn't fit on the roller.

With the new engine in, we figured it was time to crank up Clampy and give it a run. We raced around the shop a few times and the new engine did great. Can you believe we broke the 39-inch Krawlers loose and did a rear-wheel burnout? (See the video on our Web site). Then we went to the dyno shop for some post-surgery numbers. The Precision Auto guys welcomed us back, and once Clampy was outfitted with the baby trailer tires and safely strapped in place, we started spinning the dyno drum.

4x4 Toyota 22re 4 Cylinder Engine Horsepower dyno Graph Photo 18091083

The results may astound you, so take a seat. Little Clampy devastated the test with a whopping 100 hp! This is up from the lethargic 59 hp it had with the deathbed 22RE. The torque jumped from 82 to 132 lb-ft...that's a 50% increase. Of course, it's easy to beat a dead horse (or dead four-cylinder), but you may recall a few years back we took Clampy to a local garage and did before-and-after dyno runs with an average tune-up. With a healthy high-mileage 22RE we only produced 83 hp and 111 lb-ft and that was without the drivetrain drag of 1-ton axles. Stay tuned and we'll give you some off-road driving impressions of this engine in a future issue and online.