Topic: New Ohio member building a Toyota/VW Samurai

[Chuck78]

Hi everyone. New guy to this forum here.

I've got an '88 Suzuki Samurai & was looking to do some further major upgrades to it...
It's on 31x10.5R16's (265/70R16) Treadwright Guard Dogs, '85 Toyota factory trussed solid axle, custom (Sky Mfg.?) rear Toyota IFS width full floater rear housing with Samurai passenger side offset 3rd member. SPOA & 7" lift, high steer, Toyita 4cyl front discs on the rear, Toyota v6 front discs on front.
4.56 diff gears. Open diffs for now. May eventually go full locker in rear & possibly Spartan autolocker in front.

The 1.6L 8v Suzuki is plenty for wheeling in low range with some t-case gears, but for road driving, adventuring out on long road trips to Colorado, or Appalachian Mountains areas and Red River Gorge area, and as semi-daily-driver useage, 21mpg and barely able to do the speed limit on flat stretches of highway don't quite cut it...
So I'm looking to upgrade to VW turbodiesel.... I'm definitely wanting a good bit more power and not willing to trade off fuel economy much for that at all. I came to realize that many of the modifications that you can do to a turbo diesel to make more power, will also still produce good fuel economy, sometimes even better. After bolting on all of the 16 valve parts to convert my 1.6 Suzuki 8 valve over to the 16 valve head, there is much else that I can do to improve the engine efficiency while still making more power dot-dot. That's about it as far as I can go with fuel economy, and I would be lucky to knock down 26mpg with that setup. With the diesel, even figuring 30% higher fuel costs, I can make substantially more torque for the same fuel expense, maybe even less fuel expense, and my fuel range will take me significantly further down the highway or down the trails before refilling. And I can also filter all of my used waste oil, and mix it in direct with diesel fuel in the summer and burn it in small proportions. Also could start hitting up restaurants for used deep fryer oil, but the IDI engines seem to do better on veggie oil than the TDI's, but I'm sure a small proportions of used fryer oil would also do just fine in a TDI.


Even a 1.6ITD-IDI cranked up a bit with pump & boost mods will really put down some power, so the Samurai transmission and transfer case were questionable ESPECIALLY if I go all out with an mTDI build as I am hoping.

The big dealbreaker for just keeping the Samurai case and upgrading to a billet case rear housing and front output nose is that the Samurai has a 1.4:1 high range, and nothing is available to make that a 1:1 - which I realize was very critical if trying to get good fuel mileage and decent highway RPMs out of a VW diesel. The TDI's make peak torque at 1900rpm & slightly above.
The IDI's make peak torque 2500-2900rpm.
Peak fuel economy cruising rpm is going to be near or spightly above the peak torque rpm. This was absolutely unattainable even with bigger tires, if running a 1.4: 1 high range...
So time to upgrade to a 1:1 high range transfer case!!!!

[Chuck78 [OP]]

So I was debating a 1990's VW MF code 1.6TD-IDI engine hopped up with a Giles modified injection pump, K14 turbo, and about 15-17psi boost. This will give me a seriously significant boost in power over the stock 69hp & 98-ft-lbs...Giles can build the pump to put out 150hp & 225ft-lbs if I run 20psi boost even, but I'm trying to keep some longevity here. 110hp/195ft-lbs in a lightweight Samurai will be pretty adequate.
this is the lightest of all of the Volkswagen turbodiesel options, and wait is definitely a concern, as one of the Samurai's biggest attributes are its extreme lightweightness & size. 286lbs vs 185lbs for the 16 valve all-aluminum Suzuki 1.6L G16 engine. That was a definite plus to the Suzuki engine/trans/transfer case - with a hopped up 8v or a 16v EFI (or 4x motorcycle carb conversion setup), power would be adequate, 16v fuel economy isnt bad, & the whole setup is incredibly lightweight...
The 1.9 IDI & TDI engines weigh a slight bit more with a 1" taller & longer block and bigger crank throws. But the perks to going bigger displacement & mTDI may outweigh the slight weight gains (30-40lbs?).
Also, a slight bit more weight up front will help out with my long-term plans of doing a Samurai factory spec LWB stretch. An Aqualu marine-grade 5/32" plate aluminium body tub would be the ultimate if I can pull it off financially. For less than half that, I can wait for an EBI Samurai reproduction rear half LWB body tub to become available later this year, and graft the stock type replica steel tub onto the front half of my SWB US Sammi. future body Work repairs will definitely be easier with steel, but that aluminum tub is seriously a rugged, and it would take a lot even to put a little dent in it! The aluminum tub with some wrap around bumpers tying back to the frame from the sides, and some serious Rock sliders to protect it from side-impact would definitely be slated for the ultimate rig. I am really trying to build this thing with longevity and fuel economy in mind as well as utilitarian purposes, and hoping that I drive this well beyond my retirement age and then some. 40 years old now.
Doing the LWB stretch and adding 150-200lbs more in engine and transmission over the aluminum Suzuki gassers will help ballast out the chassis for better towing capability, as I would really really like to pull a small motorcycle trailer behind this with a couple of dirt bikes, or one of my dirt bikes and one of my street bikes.

[Chuck78 [OP]]

So I was also looking at the mTDI option (mechanical TDI for simplicity) for less boost required (less stress on engine components) to make similar power as above. Also, the TDI's, with much lower compression ratios vs the older IDI's as well as by the design/nature, is a better cold starter as frigid winter temperatures get below 15 degrees F or so...
TDI's also have no pre-chamber cup steel inserts in the aluminum heads, so one less thing that could go wrong there.


These kind of power figures really are warranting a Toyota R150/R151 trans...or at least a W56. I'm really shooting for the R150/R151F for the best of the bunch, longest lasting.

Also I have started considering a VW ALH model 1.9TDI, as they are far more plentiful in the wrecking yards these days, and can be had for significantly cheaper than a 1Z/AHU 1st gen TDI, or a 1.9TD-IDI "AAZ" Canadian import engine. Also, these are the 1st of the newer generation of the TDI engines, and have metro alloys / metallurgy than the older engines even, and we'll run significantly longer before the cylinder bores need overbored. They also no longer have the intermediate shaft set up with extra seals and bearings to wear out, to turn the oil pump shaft water pump etc.  Less chances for leaks!
This is also I believe the last of the TDI engines that uses a Bosch VE injection pump. It is electronically controlled, but is not too far off from the mechanical versions of this pump, and parts from this can be adapted into other model Bosch VE pumps to make it a mechanical TDI.

The downsides are that no engine mounts or other accessory bracketry or tech support are available when swapping this into a samurai other than the bellhousing adapter. Custom mounts can be fabbed. It will likely get the engine and trans clocked 15 degrees to the passenger side for slightly more oil pan clearance to the front axle 3rd member, which will also help with floor to transfer case clearancing, as well as transfer case output heights.

[Chuck78 [OP]]

So my big dilemma comes down to transfer case options since I have a very awesome rear end setup already, which is set up with Toyota v6/full floater parts and utilizes the less than common passenger side Samurai offset...

Land Cruiser transfer cases utilize passenger side offsets front and rear...
1985 or 1990+ saw the availability of the sought after R151F transmission with a special rear housing and transfer case mating shaft/coupler to run the "splitcase" style of 1980+ Land Cruiser transfer cases... I have a line on one of these used, missing the transfer case, and with 5th gear issues.it has the broader AX15 2nd-3rd gears (2.33 2nd) and with a deeper crawler 1st gear of 4.31:1 vs the R150/AX15 at 3.83:1. W56 has similar 5th to the R151F/R150F @ .83 od, but a middleground deeper 3.95:1 1st than the AX15/R150F.

This sounds like a no brainer here! I may have to import an HZJ73 or HZJ79 transfer case, however or other J7# variants.  I'm not sure if the 1980 - 1990 us version splitcase transfer cases are 100% compatible, although the outside pattern of the gasket is looking to be identical, there is a divider plate casting across the middle on the newer versions that may isolate the oil lubricating the rear bearings to the top half of the rear trans case housing, I will have to investigate this further, I'm not really sure how the lubrication works there.

The newer 1990's/2000's 70 series Land Cruiser transfer cases come in many versions that are full-time 4 wheel drive with a viscous coupler center differential setup as well. If I were driving in the snow a lot, this would definitely be a plus, as I would not have to worry about switching in and out of 4 wheel drive when I hit dry pavement, but also is a big detractor from the fuel economy, so I will probably just stay with a selectable transfer case high / low setup.

there are deeper gears available for these cases, but the gear sets will also affect the high range slightly. Swapping the ax15 5th gear with a small spacer turned up on a lathe will help recover that, and also the r154 transmission has a much deeper overdrive, although I had read someone saying that it works out to be less have a sleepover drive when you figure in the cluster ratio? This I am not educated on. In the same thread, someone said the gears from the infamous Aisin R154 Hino/Dyna transmission (donor for the 5:1 1st gear cluster to fit into R150's) would give the lowest numerical output ratio. The R154 is listed as .76:1 if I recall.

[Chuck78 [OP]]

So my top choices as of now would be a VW ALH 1.9mTDI with a Land Rover 2.5L 200TDI Bosch VE mechanical injection pump. It's nearly a direct bolt on to aVW ALH using the ALH bracket and pulley.
Then trying to run an R151F  from an HZJ73 Land Cruiser, mated to a VW ALH 1.9TDI, using a Diesel Conversion Specialists adapter for the 22R/W56 that utilizes the stock Toyota flywheel and starter. The ACME Adapters bellhousing adapter will work, but then I am on my own as far as getting a flywheel to mate up to the VW crankshaft. The Diesel Conversion Specialists kit has a thicker/aluminum dowel-pin-located fancy CNC'd 6061 T6 adapter, and utilizes a crank hub adapter to be able to bolt the Toyota flywheel direct to it.
the only problem is, this kit is only designed for the w56 transmission, not it's more rugged big brother.
No problem at all if I have the 22rte turbo transmission bellhousing that mates the r150 1/2 a 22r engine block, but these things are getting hard to find! I just missed out on one on eBay trying to make offers for a better deal, should have taken the deal at $420, as I procrastinated a half day on the acceptance of that offer, when someone else had already come in and swooped it up for $475 buy It now price!
If can go Advance Adapters R150/R151 to W56/22RE bellhousing kit, to utilize the readily available w56 bellhousing, but I will run into slight compatibility issues between the two different adapter kits at either end of the bellhousing. The Advance Adapters kit works fine if you are going straight to the crankshaft of the 22R, but the very nice looking Diesel Conversion Specialists ALH 1.9TDI to W56 adapter kit includes a special crank adapter hub with a pressed in pilot bearing. the advance adapters w56 bellhousing to R15#F series transmission includes a special extended (by 15mm) pilot BUSHING. This does not appear compatible with the Diesel Conversion Specialists pilot BEARING style 6061 T6 crank hub adapter.

my only option this route is see if they can make it with an extended snout / register for the pilot bearing, being 15 mm further back protruding towards the transmission. Obviously the 22RTE R151F bellhousing will work better/easier here.... of course I could also probably turn something up on the lathe fairly easily that would locate perfectly on the existing flywheel adapter from this kit oh, but I may be able to see if they can do a one-off for me and make one that has the pilot bearing register area extending out 15 mm further.
I will have to look at a 22R flywheel and crankshaft to see if there is even enough metal that would be able to protrude beyond the flywheel there to do this safely.


If I were going with an AHU TDI conversion, I could just use the ACME ADAPTERS kit, but the flywheels are different ALH to AHU.

also going alh vs. Ahu, I have to fabricate my own engine mounts, and deal with any other issues. The acme adapters kit that works for the 1Z/AHU engines and the older 1.6 + 1.9 IDI's has all of the swap issues figured out, and includes nice engine mounts, optional angled oil filter adapter to clear the frame, rear water housing/temp sensor bungs to clear the firewall, & has all of the applications for radiator hose sources already figured out.

But the longevity of the ALH & direct bolt-on of the Bosch Land Rover 2.5L 200TDI/300TDI pumps and the lower price and more readily available nature of the ALH engines is very appealing. durability and longevity as well as trying to set this up with the best stuff that I can for the long-term are definitely important factors here. I can keep running the Suzuki gasoline stuff for the time being as I slowly piece together all of the conversion parts needed to do the ultimate swap.