1HZ Swap

When I found this neglected factory soft top FJ40, I had plans for a total frame off restoration. The idea of using the stock F engine and 3 speed transmission, however, did not appeal much to me. Since I already have a trail rig with a Chevrolet V8 engine and transmission, I want this one to be as near factory as possible with some concessions to practicality and driveability. The aim of the restoration of this vehicle is not to build the biggest and meanest trail vehicle, but a unique Land Cruiser that most Toyota purists would approve.

Initially I thought of getting a gasoline, fuel-injected 1FZ-FE engine. Transferring the complicated electronics was a necessary evil, but most of these engines in the US are only available with an automatic transmission. I would have to obtain the engine from another country to get the manual tranny. After researching Australian wrecking yard web sites, I quickly came to the conclusion that a Toyota diesel engine swap would be easier and cost just marginally more. Plus, for the amount of work the 1FZ-FE would have taken to swap, I could have a diesel!

Through the help of John Douglas , we began searching for a good diesel engine. A 1HD-T was located, but it was more than I was willing to pay. Soon a 1HZ was found. Some poor government wagon got buggered in the rear with only 70,000 km on the odometer. Money was sent and the engine was mine!

Some quick measurements were done. We roughly calculated that the engine would fit into the 40 series engine bay, but there may be some problems with the rear driveline length. Butch Lewis , the cruiser guru from ButchBuilt cruisers, suggested that if any problems develop, the rear axle can be moved back a few inches by reversing the rear springs. John crated up the engine really nicely and sent it across the ocean.

After a good prep work, the old F engine is removed. Just for fun we started the F engine after making sure there was adequate oil in it. After three attempts, the old girl sputtered to life! Unhappy to be awake after being asleep for some 10 years to be sure, but awake nonetheless. When the engine was out, the 1HZ was maneuvered into place.

Measurements were taken. The 1HZ-H150F-HF1A combination is loooong. Even with minimal 1" clearance between the firewall and the cylinder head, the space between the fan and the radiator will be tight. I guess I'm lucky it's a diesel, as heat problems may be less than in a gasoline engine with the same displacement.

Transmission to tub floor clearance is also a problem. The much longer tranny hits the tub way before the cylinder head gets near the firewall. This is solved by cutting the floor all the way to the transmission cover mating surface. We still will have to extensively modify the tunnel cover to account for the much taller transfer case.

The main disadvantage of such a long drivetrain is the resulting short rear driveline. Avoiding a steep driveline angle also prevented us from mounting the transmission and transfer case higher out of harms way. Fortunately, this rig is mainly a restoration rig that will never see a hard trail. Here, the stock HZJ80 crossmember was extensively modified and used for rear mounting.

All in all, despite some of the minor drawbacks, the engine swap proceeded smoothly, thanks to Butch's fabrication skills. Here are shots of the ButchBuilt engine mounts. Don't expect to see these available on the 'net soon though, as they're custom made. Note the use of stock HZJ80 engine rubber isolators and the stock head pipe. It is amazing how these pieces just seem to fall into place in the 40 series chassis. Certainly Toyota did not design it that way?

Stay tuned on further developments, as we tackle the transmission cover . . .