Engine Family Comparison: 1HZ, 1HZ-T, 1HD-T, 1HD-FT (1 Viewer)

FJBen

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Not that I’m trying to sway you, but a tastefully built 2F 40 is worth a lot right now...that 75 may be closer than you think. :cool: :beer:

picture1-jpg.498319



I say build the 40 and adventure how you want. Almost all of us have stories of FJ40s from our youth.
 

Will Van

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Just curious if you considered a modern B series motor? 14-15B series? I’ll be in same boat when my 3b packs it in. I do have a spare. But the idea of a modern DI Toyota diesel is kinda nice.
Since I already have the swap kit for the 1H series of engines, I haven‘t really considered anything else.

But a 12HT would be cool too.
 
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Disagree. The degradation of BEBs in some 1H-series of motors is well established.



It is speculation that the cause of BEB degradation is due to a crank oiling problem. "Crank Oiling Problem" is a very broad explanation for BEB degradation.



Is this the research paper you are referring to? That's a very interesting research paper and might be helpful to solving the BEB degradation. But I think it's important to keep in mind that the research paper:
  • Is testing a generic inline 6 diesel engine with at least 7 main bearings. No specific mention of 1HZ, 1HZ-T, 1HD-T, 1HD-FT, 1HD-FTE, or any Toyota Diesel engine is made.
  • Is discussing and testing the main journals of a diesel crankshaft. Not the BEBs.
  • Is NOT testing for degradation of bearings due to cavitation or degradation for any other reason.
  • Is testing for noise above 5kHz in the main bearings.
  • The paper explains that the cause of the noise is from:
    • (1) the cavitation of oil on the bearing surface; and
    • (2) vibration of the main journal.
  • The paper concludes that the noise can be prevented by adding grooves to the bearing surface, preventing the cavitation from reaching the edge of the bearing and causing the 5kHZ noise.
  • Cavitation erosion is occurring during the tests, but the paper makes no mention for preventing cavitation/erosion on bearings of any type.
  • A Toyota engineer was on the team.

I also reviewed this article on the 1HD-FTE. Toyota added grooves to the main bores of the FTE to transfer grooves into the bearing surface of the main bearings, presumably to reduce noise. There is no mention of BEBs or big end conrod modifications.



True. But how do we prevent BEB degradation? Is it due to cavitation erosion? Should we increase the oil pressure? Add aftermarket BEBs with grooves or chamfers? Reduce running clearance? Run harder bearings? Switch to 1HD-FT conrods?

Cavitation is the oiling issue and that same issue that damages bearings. Exactly which bearing is going to go first is best found by making thousands of them and sending them out for real world use. The users found it. Adding grooves is a sort of fix.

There are far too many coincidences for a Toyota engineer to be involved with that paper. Toyota haven't made many 6 cylinder diesels and they don't make engines just for academic research purposes. Especially engines with specific problems like this.
 

SNLC

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I suppose a 1HDT is still worth a look. They are getting harder to find though in good condition and still command a hefty purchase price. $5k average, depending on source.

I would go 1HDFT all the way, the 24-valves is just that much better. It is arguably the best turbo diesel Toyota ever made. Hard to find though but not a lot more than a 1HDT.

You can also go the FTE, much easier to find but more expensive, swap pump for the FT and you are good to go.



I honestly wouldn’t consider any of the other diesels. Sure they are ok, can get the job done and maybe for less than the 1HDFT but why? Budget I guess, access to a good engine for cheaper too. Hard to find good FTs but if not in a rush, it’s worth the time to find a good one.

Not sure if you are watching the build thread but we are putting an FT in a 67
pickup right now.

Cheers
 

SNLC

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Thanks Juan. I have a brand new H55F for my 2F right now. I’ll have to swap input shafts but should be good to go.

I have Crushers engine swap kit, so the layout of the engine should be good.

How much does a 1HD-FT weigh? I’ve read they’re about 750lbs. Whereas the 2F is about 780lbs. Either way it seems like they’re comparable weight-wise.

The are also comparable size wise. I measured the F in comparison to the FT before buying the FT to ensure no size fitment dramas.

Cheers
 

SNLC

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Ive been running an H55 behind an FT, with the smaller 275mm flywheel and heavy duty terrain tamer clutch. I was told the FT has too much torque and power for that setup. I've had this setup for 3 years with no clutch slippage or noticed any degradation in the transmission. With that said, I do not think the H55 is well suited for the US type of driving, where cruising speeds are much higher then Japan or other parts, irregardless of the type of motor. First gear is too low making it useless on the road, good for crawling, overdrive also sucks, causing high revs when cruising. Although synchronized, it is older tech so the shifting is clunky and not effortless like the newer transmissions. I am actually getting ready to swap in an H151 which was paired with the FT and FTE by Toyota and comes with a large flywheel and finer spline input shaft, curious to see how they compare.

Have you driven an H151? They are also a clunky 5spd, long throw as well.

Honestly, the R151 drives and shifts best but it is not a hd trans.

Cheers
 
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Just curious if you considered a modern B series motor? 14-15B series? I’ll be in same boat when my 3b packs it in. I do have a spare. But the idea of a modern DI Toyota diesel is kinda nice.

They are still using them in some markets. The B engine has probably evolved more than any other Toyota diesel in the 3-4 litre sizes. Most of them are pulling around small tip trucks and buses in developing countries. Tough engines
 
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Have you driven an H151? They are also a clunky 5spd, long throw as well.

Honestly, the R151 drives and shifts best but it is not a hd trans.

Cheers

I have not driven one, but yes I've heard they are not a whole lot smoother, my biggest complaint with the 55 is the poor overdrive gearing, at least the 151 comes with a taller ratio and there are aftremarket gears that can be installed to increase that even more. If the 55 had that option I'd probably just rebuild it and stick with it. I know they make a short shift kit for the R151 do you know if that is interchangeable to the H151?
 

SNLC

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I do not believe the short throw kit is compatible.

Nothing wrong with an h151 I was just mentioning it is similar to how an H55F shifts.

Cheers
 

SNLC

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I have not driven one, but yes I've heard they are not a whole lot smoother, my biggest complaint with the 55 is the poor overdrive gearing, at least the 151 comes with a taller ratio and there are aftremarket gears that can be installed to increase that even more. If the 55 had that option I'd probably just rebuild it and stick with it. I know they make a short shift kit for the R151 do you know if that is interchangeable to the H151?


H151 actually has a worse 5th ratio than an H55. 1st in the H55 is the same as all US spec H42's


Cheers
 
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So guys this helps a lot when planning a build, doing upgrades or swaps. I like this one,


Run all your numbers through there. FT redlines at 4k, no worries at all cruising it at 2850rpms all day long. For us and the 67 pickup build, that is 85mph in 5th with an H55.

Cheers

So you are planning to run a 55 in that build with an FT? If so, what are some factors that led you to make that decision, as I am sure you had all transmissions available as an option.
 

AussieHJCruza

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H151 actually has a worse 5th ratio than an H55. 1st in the H55 is the same as all US spec H42's


Cheers
Isn't H55 first more like a H41? I think that must be a typo on Marks site
 

AussieHJCruza

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I have not driven one, but yes I've heard they are not a whole lot smoother, my biggest complaint with the 55 is the poor overdrive gearing, at least the 151 comes with a taller ratio and there are aftremarket gears that can be installed to increase that even more. If the 55 had that option I'd probably just rebuild it and stick with it. I know they make a short shift kit for the R151 do you know if that is interchangeable to the H151?
Sounds like you want a H152 which is H150 first, 151 second, third and 4th are the same as both and .75 5th gear
 

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