1HZ-T vs. 12H-T (1 Viewer)

[Dougal]

actually if the 12H-T it's 8PSI factory boosted .. and with this boost make the same amount of powa that makes the 1HZ NA .. why if you buy a 1HZ and turboed it .. need to go 15 PSI ..?

If where me .. and get a nice ( or new ) 1HZ and love the reliability .. will push it as same as 12H-T is .. and will probably end with better numbers anycase .. 8PSI ..

If I get a 1HZ for fun .. mmmm .. not .. I will stick with the 12H-T or jump to 1HD-T engine ..

In the same line diferent scenario I push my 2H-T to 14 PSI just for fun .. coz it's my fun Cruiser ..

Or get a 1HD which beats them both.
Then a 1HD-FT which does it again.

I just don't get the 1HZ lust thing. They've never impressed me.

 

[Stone]

actually if the 12H-T it's 8PSI factory boosted .. and with this boost make the same amount of powa that makes the 1HZ NA .. why if you buy a 1HZ and turboed it .. need to go 15 PSI ..?

I have a hard time believing that the naturally aspirated 1HZ has the same performance as the turbo charged 12H-T...seriously. Does anyone making this claim have power curves of the two stock engines to compare and back up their claim?

I mean the maximum ratings may be similar, but one being turbo charged and the other NA, I would imagine that those numbers develop at very different RPM's.

 

[Tapage]

I mean the maximum ratings may be similar, but one being turbo charged and the other NA, I would imagine that those numbers develop at very different RPM's.

Well actually I thing as same as you do .. but that's why I was refering to the " oficial " numbers ..

Anycase the 1hZ make the powa in a pretty much higer rpm range compared to 1HD-T and 12H-T .. but if we see the numbers .. make sense think about more performance out of a 1HZ after a well suited turbo ..

 

[Dougal]

I have a hard time believing that the naturally aspirated 1HZ has the same performance as the turbo charged 12H-T...seriously. Does anyone making this claim have power curves of the two stock engines to compare and back up their claim?

I mean the maximum ratings may be similar, but one being turbo charged and the other NA, I would imagine that those numbers develop at very different RPM's.

The only 1HZ I've driven felt torqueless. It winds up to deliver around 100kw but it's almost linear with no surge of torque that a turbo provides.

 

[dhc4ever]

The 1 hz doesnt have a great reputation for reliability if turboed with boost over 8 to 9 psi. The pistons and the heads are known to crack at higher boost pressures.
Some have died in as little as 20,000 km others have 200,000km out of theirs with no problems.
If you turbo the 1hz and price is no object put in the heavy duty rods and pistons, intercool it and keep boost to a max of 9 psi.

Much better IMO to source a factory turbo 1HDT or the 24 valve 1 hdft, both are capable of running 15 psi boost all day, just replace the big end bearings every 100,000km.

Cheers

 

[roscoFJ73]

I just don't get the 1HZ lust thing. They've never impressed me.

Which Toyota diesel do you own?

 

[Clint79]

I thought it was about 12h vs hz, you know, 2h is totally different thing...

Sorry i thought i read something about 2h with turbo but a sahara witha 12ht was i cruised around in once was still not as poki a some hz-t 's ive been in

The 1 hz doesnt have a great reputation for reliability if turboed with boost over 8 to 9 psi. The pistons and the heads are known to crack at higher boost pressures.
Some have died in as little as 20,000 km others have 200,000km out of theirs with no problems.
If you turbo the 1hz and price is no object put in the heavy duty rods and pistons, intercool it and keep boost to a max of 9 psi.

Much better IMO to source a factory turbo 1HDT or the 24 valve 1 hdft, both are capable of running 15 psi boost all day, just replace the big end bearings every 100,000km.

Cheers

Must have to do a good job to crack a cast iron head

I drive a hdj80 with intcooler and 15 psi yea it pulls well and you dont have to put your foot down much just let the boost do the work yadyada each day for work but imuch prefer to jump in my 1fz-fe to drive

 

[Dougal]

Which Toyota diesel do you own?

Technically I have part shares in a 1HD-FTE and two 1KZ-TE's.

 

[Combat Chuck]

Suddenly, I feel like I've just walked into a room with a Priest, a Rabbi, a Pastor, an Imam, and a Nihilist, and asked: "which way's better?".

 

[Dougal]

Suddenly, I feel like I've just walked into a room with a Priest, a Rabbi, a Pastor, an Imam, and a Nihilist, and asked: "which way's better?".

Welcome to the internet.

 

[Clint79]

Btw how come you want to take the chev out ,id understand if its a chev diesel but not so much a petrol/gasser

 

[Combat Chuck]

Btw how come you want to take the chev out ,id understand if its a chev diesel but not so much a petrol/gasser

I have several reasons.
1: I'm planning on this being more of an expedition build, and would like the better range.
2: I'm fed up with GM.
3: I don't want to remove the "Toyota" badge from the grill of my '40
4: Diesel strikes me as being more efficient, overall, and considerably more simple.

Most notably: I currently drive an Oldsmobile Delta-88, and am disgusted with just how over-complicated everything is, and how its those complications that seem to fail, and I'm seeing this trend in all things made by automotive companies in the 'States.
Also, I'd rather pay a Japanese company for pats that are made in Japan, as opposed to paying an American automotive company for parts that are made... elsewhere.

I hope this makes sense.

 

[rideglobally]

exactly how i felt ....... so i just got the 12th and be done with it.

Suddenly, I feel like I've just walked into a room with a Priest, a Rabbi, a Pastor, an Imam, and a Nihilist, and asked: "which way's better?".

 

[roscoFJ73]

I have several reasons.
1: I'm planning on this being more of an expedition build, and would like the better range.
2: I'm fed up with GM.
3: I don't want to remove the "Toyota" badge from the grill of my '40
4: Diesel strikes me as being more efficient, overall, and considerably more simple.

Most notably: I currently drive an Oldsmobile Delta-88, and am disgusted with just how over-complicated everything is, and how its those complications that seem to fail, and I'm seeing this trend in all things made by automotive companies in the 'States.
Also, I'd rather pay a Japanese company for pats that are made in Japan, as opposed to paying an American automotive company for parts that are made... elsewhere.

I hope this makes sense.

One thing this thread has missed is that most Toyota diesels need their own gearbox or the input shaft to be swapped over.
If you can get the gear box with the engine,that will make it easier.
The F engines share the same input shaft with the 2H and 12HT.
All the diesels had 5 sp by 84 although there are some odd exceptions.
1HZ and 1HD T also have different gearboxes to each other but they can be swapped over using a Isuzu clutch and the correct flywheel

 

[rutbeer]

Suddenly, I feel like I've just walked into a room with a Priest, a Rabbi, a Pastor, an Imam, and a Nihilist, and asked: "which way's better?".

Yup, and nobody has even suggested the 13B-T or 15B-T yet.
You did say you were dropping this in a 40 series, correct?

 

[Combat Chuck]

One thing this thread has missed is that most Toyota diesels need their own gearbox or the input shaft to be swapped over.
If you can get the gear box with the engine,that will make it easier.
The F engines share the same input shaft with the 2H and 12HT.
All the diesels had 5 sp by 84 although there are some odd exceptions.
1HZ and 1HD T also have different gearboxes to each other but they can be swapped over using a Isuzu clutch and the correct flywheel

I forgot to mention my plan was to buy a pull-out motor with a tranny, I'm hoping on finding one with an H55F.

Yup, and nobody has even suggested the 13B-T or 15B-T yet.
You did say you were dropping this in a 40 series, correct?

yessir, '72 40, doing a semi-frame off refurbish (Thanks to Crushers for the correct alternative for "Restore")
It came with a 350 SBC, and my original plan was to have to motor rebuilt with Vortec heads and manifold, replace the j30 tranny with an SM456 and a Ranger overdrive and slap on an orion, but after all that, I'm starting to feel like I'm just going to end up with a Blazer in a smaller footprint, not a real Land Cruiser.

 

[roscoFJ73]

I forgot to mention my plan was to buy a pull-out motor with a tranny, I'm hoping on finding one with an H55F.


.

Not trying to throw a spanner in the works,but if you plan to roam far and wide in a cruiser,wouldnt you be better off with a LWB model,like a 60 or 45?
Just something to think about before the $$$ start flowing.

Some 12HT and 1HZ pics. This 12HT had done 500000+klms with a no oily sludge anywhere,just a light coat of dust.Its sitting in its 60 series engine bay

 

[Combat Chuck]

Not trying to throw a spanner in the works,but if you plan to roam far and wide in a cruiser,wouldnt you be better off with a LWB model,like a 60 or 45?
Just something to think about before the $$$ start flowing.

Some 12HT and 1HZ pics. This 12HT had done 500000+klms with a no oily sludge anywhere,just a light coat of dust.Its sitting in its 60 series engine bay

Nice pics, those are some clean engines.

The LWB suggestion is something I've contemplated, but ultimately, I'm happy with my 40, sure, cargo space is a little tight, but I don't plan on bringing too much along with me. I'm a hardcore minimalist, so all my personal gear takes up less than the space of a person when stowed. For an expedition, the most space I'd need is for Dutch Ovens and charcoal.
Otherwise, my main goal is to have this be my headquarters vehicle for backpacking and the like.

 

[roscoFJ73]

The 1HZ. These are of mine a/c pump missing.
Another tick for the 1HZ is its 120 amp alternator(75,78,79 series) which is cheap(ish) and easy to replace.

The 13BT,2H and 12HT have a 60-80 amp alternator with the vac pump on the alternator and not so cheap and easy.
Im not even sure if they are in production now.

 

[roscoFJ73]

The LWB suggestion is something I've contemplated, but ultimately, I'm happy with my 40, sure, cargo space is a little tight, but I don't plan on bringing too much along with me. I'm a hardcore minimalist, so all my personal gear takes up less than the space of a person when stowed. For an expedition, the most space I'd need is for Dutch Ovens and charcoal.
Otherwise, my main goal is to have this be my headquarters vehicle for backpacking and the like.

Cool. I spent s***loads on my 73 series 1HZ conversion and ended up buying a 75 because I can sleep in it , carry supplies for weeks if need be tand its also much more comfortable being a LWB.