Positioning the engine
Make no mistake, the Toyota 1VD engine is large. Being a 90º, quad cam V8 it is very wide and doesn't actually fit into the 100 series bay very easily. It's also quite high, with a big intercooler and other componentry sitting on top of the engine.
Because of it's massive width, there is no hope of the engine sitting back in the firewall where the 1Hz was, meaning I had to move the entire engine/gearbox assembly forward by about 100mm. This created problems using the original 1VD engine cooling fan (due to fouling on the radiator), and also necessitated the fabrication of a gear lever linkage, because the new gearlever would be located some 250mm forward of the original location, which put it under the dashboard. 150mm of this difference is due to the 70's gearbox having a different gearlever location to the 100's gearbox, while the remaining 100mm is due to the forward move of the assembly. I did consider 2 other options:
- Space the engine/gearbox: This would have solved the gear lever position issue, but it would have been a huge undertaking to build a new bellhousing and then fabricate an input shaft extension. This option went into the too hard basket, but should be possible with the right equipment and enough time.
- Cut and reform the firewall to allow the engine to sit back: This would have solved both fan and gearlever problems, but there is too much equipment under the dash that would have needed to be relocated or removed (eg fan and A/C). I don't think this would be a feasible option for anyone who wants to retain the original equipment of the 100. However, for a comp rig not requiring A/C etc, it could be an option.
I didn't have much choice when it came to final positioning of the engine.....
Front - Back:
I wanted the engine as far back as possible, but was limited by the firewall and width of the engine. I decided on a minimum of 20mm clearance to the firewall, and positioned the engine there.
Side - Side:
Again, it's a very tight squeeze. The passenger/near-side position is dictated by the turbo oil return line, which ended up about 10mm from the near-side chassis rail. On the driver's/off-side, there is only about 10mm clearance from the exhaust manifold to the steering shaft. So there is really no room to move in either direction.
I would have preferred to lower the engine further into the bay, but this is prevented by two things. First, the turbocharger (on the near side) is only about 15mm above the chassis rail, and the size and shape of the sump means lowering it further would have risked impact with the front axle on full uptravel. As it was, I have decided to increase the height of the bumpstops by 50mm to prevent impact.
Other than scalloping out a section of chassis, there is little that could be done for the turbo, and the sump is a very complex piece of alloy equipment, with an inbuilt oil cooler and numerous oil return lines. I don't doubt that a more friendly shaped sump could be produced, but with the turbo positioning I saw little benefit to be gained.
Fabricating and positioning the engine and gearbox mounts
I had planned to retain the original gearbox crossmember and modify it to move the gearbox forward, but after some trial and error decided to make a new one from scratch, due to the difficulty in preventing it from fouling on the transfer case and/or driveshafts. I used 75x50x3 RHS tube reinforced with a 5mm plate across the bottom, with a 100x50x3 RHS section on top to lift the gearbox 50mm above standard. I attached the RHS to the original crossmember mount points using 10mm flatbar with 5mm flatbar gussetting from the RHS.
I built and positioned the new crossmember while the engine/gearbox assembly was still suspended, then bolted it up to secure the rear of the assembly, before starting work on the engine mounts. The new crossmember places the gearbox mount 100mm forward, and 50mm higher than the original position (See body lift section below).
It's necessary to cut both original engine mounts from the chassis, as they are not in usable positions for the new motor.
The first engine mount I made was the near-side. I used the original engine-to-rubber-mount section, and then fabricated the section from the chassis to the rubber-mount and welded it to the chassis. This was fabricated using 5mm flatbar, and basically resembles the original factory mount. I can't give measurements and angles, as I found it easiest to fabricate it as I went.
The drivers side mount was more problematic as the engine-to-rubber-mount section also had to be replaced due to it fouling on the chassis and steering shaft. I fabricated this section from 10mm flatbar, then used the original rubber mount and fabricated the chassis-to-rubber section in a similar fashion to the near side.
Photos (Click to enlarge):
New Off-side inner mount
The main gearlever linkage was fabricated using both the 70 and 100 series gearlevers, 1x 1/2" female and 4x 1/2" male Rose Joints (aka control rod ends) along with some steel plates and other hardware.
I used the transfer case lever from the 70-series, bolted to the rear of the plate I fabricated for the gearlever linkage. The lever attaches to the transfer case with a shortened linkage. The lever sits in the same relative location as the original 100-series transfer lever, but it does move further as it must travel from H2-H4-N-L4 instead of just H-N-L.
Video of linkage operating and linkage photos (Click to enlarge):
Air Box (Updated 8/2/10)
The 70-series wreck had a destroyed airbox, and with Toyota asking a truly ridiculous $1100 for a replacement, I decided to go with an off-the-shelf Donaldson airbox and adapt it to both the 1VD intake pipe and the Safari Snorkel fitted to my 100.
The Donaldson I chose was an FPG-9 (#G090219), which was the largest unit I could fit in the space available. This unit offers excellent airflow and the large filter minimises cleaning. Additionally, Donaldson't cellulose-paper elements are water washable and so can be reused several times.
Front and Rear driveshafts
With the forward move of the engine/gearbox assembly, it was necessary to lengthen the rear driveshaft and shorten the front driveshaft.
As I've mentioned, I decided to go with the taller 3.909:1 diff ratios of the 70, rather than the lower 4.3:1 ratios in the 100. The diff centres of the new 70 and the 100 are interchangeable, so I could have simply removed the entire front and rear carriers and swapped them over. But as I had air-lockers in the 100, I took all four centres to JMac in Arndell Park and had him swap the crown wheels and pinions between the centres.
After finalising the position of the engine, I found it sitting higher in the bay than I would have liked, and on a slight angle down to the back. The height at the front was necessary to give adequate chassis clearance for the turbo, sump and manifolds, while the lower position at the rear was to allow the gearbox clearance under the transmission tunnel.
Once I discovered the engine wouldn't fit under the bonnet I toyed with the idea of fitting a bonnet 'bulge' (think XR8 Falcon), but after consulting an engineer to check legality, decided to do a 50mm bodylift instead. The advantages of this option were:
- Gave clearance for the engine under the bonnet without the need for a bulge.
- Gave clearance for the clutch master cylinder over the engine rocker cover.
- Allowed me to lift the gearbox by 50mm, reducing the engine angle and improving transfer case ground clearance.
The 100series has twelve body mount points. Ten of them have 10mm bolts through from the body to the chassis, while two are simply pads under the load area. These two pads are mounted blindly under the load area without through bolts and only actually contact the chassis when a load is added to the rear of the vehicle.
I used 65mm MoS2 filled Nylon rod to make the bodylift mounts. At $90/metre from Cut To Size Plastics at Yennora, it's cheaper than steel or aluminium, while also minimising the transmission of vibration and reducing the creaking and groaning common with metal body lifts.
I cut the nylon into 50mm sections on a lathe. For the ten main mounts I drilled 10mm holes through the centre, while for the two pad mounts I drilled 9mm holes, then screwed in 3/8"x2" coach bolts and cut off the heads allowing the top 10-15mm of the bolt to protrude out the of the mount (see picture). This protruding bolt section locates in the chassis under the pad and prevents the nylon mount from falling out when there isn't any pressure on it. I also used a little silicone under the nylon to prevent any vibration or rattling.
Photos (Click to enlarge):
Body mount access holes
The machined nylon mounts
Installed - Pad
Update 12/12/09: To feed air to the intercooler, I installed a bonnet scoop from a 2008-09 model Holden Colorado Turbo-Diesel. There were no other vehicle or off-the-shelf scoops that were large enough to feed the 1VD's sizable intercooler and fit the bonnet of the 'Cruiser.
Holden are asking a whopping $680 for this scoop (Don't you love genuine parts?!), but they were unable to get one for three months. Before trying Holden I made a few unsuccessful calls to wreckers, but the Colorado was too new to be common. However, after Holden couldn't get one I spent almost a day on the phone ringing about a hundred wreckers around Australia before I finally found one for a much more reasonable $270.
The scoop looks pretty good and fits the curve of the Landcriser's bonnet well. It's almost the same width as the intercooler and lets in plenty of air.