Speed limit in 60 series' 2H and 12H-T

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Hi everyone!

I am from Gabon ( in the central region of Africa). I recently got interested in collecting a few 60 series, diesel so far (2H, 12H-T engines).

I have driven a couple of 2Hs and 12H-Ts at full speed, or at least I pushed them as fast as I could on the highway, but I have noticed, they would very rarely go beyond 100 Kmh (62.14 mph).

I must confess the 12H-T engines had the turbo removed by the previous owners, but still, they were able to go up to 70/80 mph sometimes, after much effort.

Well, I know that as old-school (underpowered-as-per-modern standards) engines, they are slow to get up to speed, but

1) why does the needle on the speedo always seems to stabilize around 60/70/80 mph while the dial ( I guess that is the right name) indicates up to 100 (2H) or 110 (12-T)?
2) Is it because most of these engines have more or less 300,000 mileage on the clock (plus probably poor maintenance history), and could they do better after a rebuild or turbo install?
3) Or is it that in some parts of the world these cars came with factory speed-limitation "modifications" that a mechanic can or cannot fix? (I saw a few vids on Youtube where these engines could a bit more easily go beyond 80 mph.

Thanks in advance for your enlightenment

Regards
NNB
 

ToyotaMatt

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ChaserFJ60

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It depends on the modifications of your engine, I think its more of an aesthetic reason the speedometer goes to 110, Frankly I would only go to 110 in a 60 series Land Cruiser if I had a death wish.

On the gasoline engines the 2F and 3FE I can push 80mph sometimes if the conditions are just right, I usually cruise at 60-70mph. I wouldnt plan on any type of modern acceleration from these trucks at all. Then again I havent ever driven a diesel Land Cruiser so I dont know the differences in drive. If you have large offroad tires and heavy gear expect to be slowed down, Routine maintenance goes a long way on how well these engines can preform.
 

kevin in okinawa

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They weren't originally designed to travel at modern highway speeds. However, if you give them some extra horsepower (increase boost and fuel) they will be able to go faster. A 12h-t without a turbo is just a weird 2H...put a turbo back on it.
 
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They weren't originally designed to travel at modern highway speeds. However, if you give them some extra horsepower (increase boost and fuel) they will be able to go faster. A 12h-t without a turbo is just a weird 2H...put a turbo back on it.
Thanks Kevin. I got that in mind definitely.
 
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It depends on the modifications of your engine, I think its more of an aesthetic reason the speedometer goes to 110, Frankly I would only go to 110 in a 60 series Land Cruiser if I had a death wish.

On the gasoline engines the 2F and 3FE I can push 80mph sometimes if the conditions are just right, I usually cruise at 60-70mph. I wouldnt plan on any type of modern acceleration from these trucks at all. Then again I havent ever driven a diesel Land Cruiser so I dont know the differences in drive. If you have large offroad tires and heavy gear expect to be slowed down, Routine maintenance goes a long way on how well these engines can preform.
Thanks, your first sentence addresses my main concern: "It depends on the modifications of your engine, I think its more of an aesthetic reason the speedometer goes to 110, Frankly I would only go to 110 in a 60 series Land Cruiser if I had a death wish."

All the best!
 
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I can pretty much bury the speedometer needle on my 12HT 5 speed HJ61 with 3.70 gears and 255 85s if I wanted to.

140 Kph is very easy, and over 160 kph is something it's not designed for and I would say "do not do this!".

~John
 
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I can pretty much bury the speedometer needle on my 12HT 5 speed HJ61 with 3.70 gears and 255 85s if I wanted to.

140 Kph is very easy, and over 160 kph is something it's not designed for and I would say "do not do this!".

~John
I got you mate, thanks for advising.
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ChaserFJ60

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I am curious, whats the fastest anyones gone in a 6X Type Land Cruiser? I topped out at I think 85MPH downhill with my 2FE, 2F Block with 3FE head and H55F
 
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I am curious, whats the fastest anyones gone in a 6X Type Land Cruiser? I topped out at I think 85MPH downhill with my 2FE, 2F Block with 3FE head and H55F
My HJ61 (with its turbo removed) has once topped 68/74 MPH, on a flat road, after pushing a little harder and it took quite some time to reach there. I guess with a turbo back to it, it can do more and a little faster.

I never tried downhill very fast though :).

I have a brand new WINK turbo waiting ( I heard it is a great one!), when I do the rebuild of my 12H-T, my plan is to put the WINK turbo with an air-to-air TMIC (Top Mount Intercooler)... with a fan and a water spay system, and boost gauge... of course.

To tell the truth, I don't what it will all add up to, I just want to try and see.

Regards
Boris
 

The Phoenician

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Fastest mine has been is 100 mph, 3FE engine, auto trans, 4.88s, 31.5" tires, flat ground and favorable winds. I have on multiple occasions driven in the same configuration at 80 mph cross country for days on end. At 80 mph and 3,000 rpm however gear whine and engine noise becomes annoying and is a not so subtle hint that you're pushing just a little too much.

Now that it has a V8 with more than double the power I'm sure it will go faster but I don't need to know how fast.

No matter what gearing changes, tires, or engine choice.. both the cruisers I drive most (76 FJ40 and 89 FJ62) seem to be "happiest" right at 62 mph, or 100kph. They'll both go faster. It's something that I have a hard time describing, but they are both very content, relaxed and smooth at that speed. It is the speed that they and I settle into without thinking about time or speed. It must be something deep in their souls that is un-changeable it seems.
 
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Fastest mine has been is 100 mph, 3FE engine, auto trans, 4.88s, 31.5" tires, flat ground and favorable winds. I have on multiple occasions driven in the same configuration at 80 mph cross country for days on end. At 80 mph and 3,000 rpm however gear whine and engine noise becomes annoying and is a not so subtle hint that you're pushing just a little too much.

Now that it has a V8 with more than double the power I'm sure it will go faster but I don't need to know how fast.

No matter what gearing changes, tires, or engine choice.. both the cruisers I drive most (76 FJ40 and 89 FJ62) seem to be "happiest" right at 62 mph, or 100kph. They'll both go faster. It's something that I have a hard time describing, but they are both very content, relaxed and smooth at that speed. It is the speed that they and I settle into without thinking about time or speed. It must be something deep in their souls that is un-changeable it seems.
Great post! I relate to that.
Thanks
 

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