1hd-ft swapped 80 with high get (1 Viewer)

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Another thing to note: these engines don’t have separate combustion chambers like IDI diesels do, they use a depression in the top of the piston instead. You won’t have “combustion chamber issues” without major piston damage.

Good point.

The head surface is basically flat. Skimming it doesn't change the combustion chamber.

It will ever so slightly change the position of injector nozzles in the combustion chamber.
 
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Is the mechanic familiar with diesels? Like, well experienced? Or more like, "yeah, we can bolt it together for ya"?

You shouldn't be feeling a lack of power with 12psi boost and the EGTs you're seeing.

Does it chug dark smoke when accelerating?

Pump tuning requires a lot more finesse than just dumping in fuel.

1400⁰f is widely considered a safe maximum EGT with the probe in the manifold. Realistically, they are safe to quite a bit higher temps, but 1400⁰f is within a normal range.

Turbo shouldn't be noisy either.
He is very familiar with diesels. He has over 35 years of diesel experience. He is not familiar with a Toyota diesel and admitted that to me before I delivered the truck to him. I trust his knowledge with diesels.

No noticeable smoke when accelerating. I can see smoke if I apply throttle when it is sitting still.

The current shop is supposed to be speaking with the guy who did the install on Monday. Hopefully he can have a few questions answered and this become an easy solution.

I'm leaning more toward the injection pump. It was rebuilt but not sure what the shop did that rebuilt the pump.
 
Are you sure there is actually a problem with the engine? The temps and boost levels you describe sound perfectly normal for a stock 1HD-FT. Lack of power can be somewhat subjective, how slow is it actually? What transmission/differentials/tire size is it running? Does the engine start well?

Could be something as simple as a tired turbo, or perhaps they used a 3FE or 1FZ spec transmission with the swap? Some more details about how the rig is set up would be good.
 
Is the mechanic familiar with diesels? Like, well experienced? Or more like, "yeah, we can bolt it together for ya"?

You shouldn't be feeling a lack of power with 12psi boost and the EGTs you're seeing.

Does it chug dark smoke when accelerating?

Pump tuning requires a lot more finesse than just dumping in fuel.

1400⁰f is widely considered a safe maximum EGT with the probe in the manifold. Realistically, they are safe to quite a bit higher temps, but 1400⁰f is within a normal range.

Turbo shouldn't be noisy either.

Are you sure there is actually a problem with the engine? The temps and boost levels you describe sound perfectly normal for a stock 1HD-FT. Lack of power can be somewhat subjective, how slow is it actually? What transmission/differentials/tire size is it running? Does the engine start well?

Could be something as simple as a tired turbo, or perhaps they used a 3FE or 1FZ spec transmission with the swap? Some more details about how the rig is set up would be good.
Transmission is an A442F that came with the motor. Truck has 37” tires and 4.88 gears, which I installed before the diesel swap. If it wasn’t for my wife and kids I would have preferred a manual swap.

Engine stars great.

It may only be slow to me due to my concern and constant concern over the egts and not pushing the truck past 1250.

Out West was terrible while getting passed on hill climbs constantly. Needless to say I got very comfortable being passed by everyone on the road.
 
what about a boost leak,
boost could still be reading 'right' but leaking causing the turbo to have to work harder to achieve the same boost numbers (at the boost probe)
and less air going through the engine...
intake manifold gasket?
 
Transmission is an A442F that came with the motor. Truck has 37” tires and 4.88 gears, which I installed before the diesel swap. If it wasn’t for my wife and kids I would have preferred a manual swap.

Engine stars great.

It may only be slow to me due to my concern and constant concern over the egts and not pushing the truck past 1250.

Out West was terrible while getting passed on hill climbs constantly. Needless to say I got very comfortable being passed by everyone on the road.
37" tires will definitely make it feel slower, my brother's HDJ81 is running 33's and maintains 60-70mph on hills, usually running 1250-1350ºF. If I had to guess I'd say there isn't anything wrong with your engine or drivetrain, these things run hotter than many people think in stock form, especially traveling in North American highway conditions. If you really put your foot into it on flat ground does it move out pretty well? Short hard pulls at high EGT won't cause any harm, I've seen north of 1650ºF on my TDI a couple of times and run it at over 1300ºF for extended periods, though I try not to do that.

Having owned a couple of 2L-TE powered LandCruisers I can sympathize with constant concern over EGT's and having to keep backing off the throttle. Ideally I would recommend fitting an intercooler, but in the absence of that you can turn up the boost a bit and adjust fueling to keep exhaust temps in check under heavy throttle. It isn't super well tuned, but my brother's HDJ81 is fairly quick (by diesel LandCruiser standards) and doesn't run scary hot. Definitely much faster than when I owned it in stock form.

Getting passed by all and sundry is pretty much a fact of life for us diesel LC owners! I generally cruise at 75-77mph (around 120km/h) on the interstate around here and still get passed regularly by almost everyone, including semis. They're the only ones I catch up with on the hills.
 
37" tires will definitely make it feel slower, my brother's HDJ81 is running 33's and maintains 60-70mph on hills, usually running 1250-1350ºF. If I had to guess I'd say there isn't anything wrong with your engine or drivetrain, these things run hotter than many people think in stock form, especially traveling in North American highway conditions. If you really put your foot into it on flat ground does it move out pretty well? Short hard pulls at high EGT won't cause any harm, I've seen north of 1650ºF on my TDI a couple of times and run it at over 1300ºF for extended periods, though I try not to do that.

Having owned a couple of 2L-TE powered LandCruisers I can sympathize with constant concern over EGT's and having to keep backing off the throttle. Ideally I would recommend fitting an intercooler, but in the absence of that you can turn up the boost a bit and adjust fueling to keep exhaust temps in check under heavy throttle. It isn't super well tuned, but my brother's HDJ81 is fairly quick (by diesel LandCruiser standards) and doesn't run scary hot. Definitely much faster than when I owned it in stock form.

Getting passed by all and sundry is pretty much a fact of life for us diesel LC owners! I generally cruise at 75-77mph (around 120km/h) on the interstate around here and still get passed regularly by almost everyone, including semis. They're the only ones I catch up with on the hills.
Can’t say that I’ve really put my foot in it given that the egts have always concerned me. As far as moving it struggles to get out of its own way.
 
My completely stock 96 80 non EGR 1HD-FT would hit 1450 pretty easily if I stayed in it when I got it. Boost pin had wear mark like it'd been riding in that range for a long time and the fuel screw still has the lock out bushing on it. Absolutely no smoke on acceleration only slightest puff on cold start for few seconds. I tried to lower it with boost pin and fuel screw but it didn't really help for as much power as I lost with still quickly rising temps. Upped boost to 14-15psi and it significantly lowered temps. Now stabilize at 1250 with quick spikes to 1300 compared to it wanting to live at 1400+ and climbing while accelerating.

In my experience these things just run a lot hotter than people say. I don't understand how people drive anywhere who claim they don't exceed 1100f/600c. I would certainly never drive even a stock one without an EGT gauge.

I have 35's on stock gearing but the power level seems decent, no plans on regearing other than maybe low range Tcase gears unless I go to 37's but I'm pretty happy with the drivability of 35's.
 
My completely stock 96 80 non EGR 1HD-FT would hit 1450 pretty easily if I stayed in it when I got it. Boost pin had wear mark like it'd been riding in that range for a long time and the fuel screw still has the lock out bushing on it. Absolutely no smoke on acceleration only slightest puff on cold start for few seconds. I tried to lower it with boost pin and fuel screw but it didn't really help for as much power as I lost with still quickly rising temps. Upped boost to 14-15psi and it significantly lowered temps. Now stabilize at 1250 with quick spikes to 1300 compared to it wanting to live at 1400+ and climbing while accelerating.

In my experience these things just run a lot hotter than people say. I don't understand how people drive anywhere who claim they don't exceed 1100f/600c. I would certainly never drive even a stock one without an EGT gauge.

I have 35's on stock gearing but the power level seems decent, no plans on regearing other than maybe low range Tcase gears unless I go to 37's but I'm pretty happy with the drivability of 35's.
What is the stock gear ratio for an HDJ81? Are they 4.30’s or 4.10’s?
 
37" tyres are going to murder your performance. Ever tried to pedal a fat bike?
 
37" tyres are going to murder your performance. Ever tried to pedal a fat bike?

My hdj80 had enough torque and power to take off in 2nd gear on 35s with stock gearing.
Take off in 1st, I'd be grabbing 2nd before being half way across an intersection.

Describing the perfornance as "not able to get out of its own way" is more than the effect of 37's IMHO
 
Are you someone who would tinker at tuning yourself?
I would if I could get the top cover off without removing the pump and/or loosening the pump and turning it away from the motor. I've watched numerous videos but most only show the 1hd-t. I can't figure out how to get an Allen wrench on the Allen bolt on the top cover of the injection pump without hitting the intake manifold. Maybe I missing something. This is one of the reasons I carried it to a diesel mechanic.

I have read about tuning these engines for months and watched numerous videos.
 
Post a photo.
Can you cut an allen wrench down?
I don't have the truck with me since it went to the mechanic but could take a picture when I get it back home. I actually bought an additional set of Allen wrenches that are for tight spaces and it still didn't fit without hitting. I can get an Allen wrench on two of the four bolts.
 
Cut the Allen wrench down so it'll be just longer than the depth of the cap screw, It'll fit. Might have to move the altitude compensator or a VSV out of the way. Find the FT pump manual in the resources section, my star wheel was still set to factory specs and seems to give me plenty of power with the factory boost pin.

Do you lack power because you're getting out of throttle when it gets hot or does it not even move from a start? When I tried to lower my temps I messed with the star wheel to lower fuel as boost came on and it made the truck damn near undrivable and didn't help my max temps at all.
 
Cut the Allen wrench down so it'll be just longer than the depth of the cap screw, It'll fit. Might have to move the altitude compensator or a VSV out of the way. Find the FT pump manual in the resources section, my star wheel was still set to factory specs and seems to give me plenty of power with the factory boost pin.

Do you lack power because you're getting out of throttle when it gets hot or does it not even move from a start? When I tried to lower my temps I messed with the star wheel to lower fuel as boost came on and it made the truck damn near undrivable and didn't help my max temps at all.
The truck is drivable but in my opinion lacks power. I have driven a 1hd-t with a manual and it feels slow as well but not as slow as my truck. Granted I daily drive a Duramax truck, which is night and day difference. I completely understand these engines are not fast.

I'm hoping after a few adjustment things will improve. Since the swap I've stayed more concerned with the egts and been unwilling to push the truck to see what it would do.

Sounds like from all the comments, which I appreciate, I need an intercooler and a few adjustment. From that point I should just drive it.
 
I completely understand these engines are not fast.
They also should not be slugs.
Tuned right, they can be a blast to drive.
Tuning can make a huge difference in performance, and EGTs

Since the swap I've stayed more concerned with the egts and been unwilling to push the truck to see what it would do.
Part of tuning is pushing it to see what your EGTs max out at.
Peak EGTs with rhe engine under loadgives an indication of the overall state of tune.
If you push it hard and never get over 1400⁰f, there is potentially room to add more fuel.
If you push it and the EGT's keep climbing, 1650⁰f -ish is ok for short stints of a few seconds or a minute or two.
Holding it flat at 1650⁰f towing a trailer over the mountains for 20 minutes wouldn't be wise. Pushing it for a minute to get passed that semi trailer before the top of the hill and the end of the passing lane is no problem.
If EGT's kept rapidly climbing beyond 1650⁰f, you definitely have a problem, but you would be seeing lots of smoke too.

Peak EGT is something that will rarely happen in normal driving.

Sounds like from all the comments, which I appreciate, I need an intercooler and a few adjustment.
Intercooler?
Not really. If your boost is only 12psi, you won't see a lot of benefit from an intercooler. You might see some gains, but there's other low hanging fruit to pluck before you jump to an intercooler.

Adjustment? Almost certainly a lot to gain with some tuning.

Find "the official 1hd-t tuning thread" and start reading at around page 40 - 45 ish.
There was a few guys working through the tuning process around those pages. I think everything needed for good tuning is covered in that part of the thread
 

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