What are the differences between the two and what trucks did they come in.
1hd-t 1hd-ft
- Thread starter BlackSmoker
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What are the differences between the two and what trucks did they come in.
Apart from the 12/24 valve they had a fuel pump controlled by a computer(can be chipped)
The FT only had a few HP more than the 1HD T. The uprade was probably more to comply with anti pollution requirements.
I think the the 1HD FT came out in 96 or 97 in the 80 series and probably the Coaster.
The 1HD-FT has NO computer, it run a mechanical pump like the 1HD-T, and it was released in the 80 series in Jan 1995.
The 1HD-FT no glow plugs (only a glow screen in the intake pipe), centrally mounted vertical injector, roller cam followers with bridged actuators for the 24 valves instead of the direct shim and bucket of the 1HD-T / 1HZ / 1PZ.
It also uses a slightly larger turbocharger (larger turbine) and in conjunction with the very "green friendly" settings of the fuel pump the stockers drove very poor under about 2000rpm, which felt like turbo lag but in actual fact is fuel lag.
It was rated for Aust. at 125kW, the 1HD-T was only 115kW.
Australia did not get EGR on the 1HD-FT, however I have seen the Jap version with the twin Vac units on it.
Easy to block off, especially if you're fitting an APS intercooler which gets rid of the different EGR spec cross over pipe.
- Thread starter
- #8
What would I need to turbo the HZ in my truck? I was told to drop th e compression to turbo. Why? No other diesel engines need to do this are they weak? I would like to propane inject and water to air intercooler. If the exhaust temp starts climbing couldn't you use water injection?
As an example, the 3B vs 13BT, the compression ratio dropped with the factory turbo. It reduces combustion temperature/pressure and some of that not so good stuff.
In theory (don't you just love that phrase?) a low compression ratio of 14 or 15:1 with a higher boost pressure and fuel would ideally make more power. That is until you tried to start the sucker.
You don't need to drop the CR to turbo a 1HZ. Or a 3B, for that matter. Or probably any other normally aspirated diesel. Don't go crazy on the boost and you should be golden.
-kevin
In theory (don't you just love that phrase?) a low compression ratio of 14 or 15:1 with a higher boost pressure and fuel would ideally make more power. That is until you tried to start the sucker.
You don't need to drop the CR to turbo a 1HZ. Or a 3B, for that matter. Or probably any other normally aspirated diesel. Don't go crazy on the boost and you should be golden.
-kevin
Compression ratios are dropped to reduce stress on the head, rods and everything inbetween. You can run low to moderate levels of boost without dropping the compression.
If exhaust temps get too hot then you've either got too much fuel or not enough air. A better intercooler is a much better idea IMO than water injection.
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- #11
I am planning to use a Garrett dual ball bearing turbo water/air inter cooler, can the exhaust be water jacketed too like on Mann diesels? What A/R on the turbo? .60 or .57? Where do you pull and return coolant and oil for turbo? So the weakest part of the HZ is the head? Is there an after market head avalable? How do you get extra fuel from the pump. I am more interested in using the HZ then the HD's. 
I am planning to use a Garrett dual ball bearing turbo water/air inter cooler, can the exhaust be water jacketed too like on Mann diesels? What A/R on the turbo? .60 or .57? Where do you pull and return coolant and oil for turbo? So the weakest part of the HZ is the head? Is there an after market head avalable? How do you get extra fuel from the pump. I am more interested in using the HZ then the HD's.
Garrett make a lot of ball bearing turbos. Which one were you looking at?
Which one you start with will dictate which exhaust housing A/R is best for your application.
Water cooled exhausts aren't necessary unless you've got a fully enclosed engine bay with little to no airflow (like a boat).
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- #14
I am looking at the GT 25 or 28 and external wastegate. I was told it is very prone to warping once turbo'd. I would like about 12-9 psi of boost and low exhaust temp. I am looking at what pump to use I think the stock one should be good enough. I would like around 200-250 HP. Keeping the EGT down is the key to turbo HZ from what I have found from reading various posts.
I am looking at the GT 25 or 28 and external wastegate. I was told it is very prone to warping once turbo'd. I would like about 12-9 psi of boost and low exhaust temp. I am looking at what pump to use I think the stock one should be good enough. I would like around 200-250 HP. Keeping the EGT down is the key to turbo HZ from what I have found from reading various posts.
Those two turbo series (GT25 and GT28) cover a fairly large range. When bolted to an engine the difference is boost at low rpm giving lots of usable torque (the smaller turbos) or boost which arrives with higher rpm for less backpressure and more power.
It really depends on what you want. 200-250hp is a lot to expect from a previously NA engine with no internal modifications. Engine modifications aside, that would take one of the larger T28 turbos (i.e. GT28RS) which would give almost no boost below 2000rpm and not give full boost until around 2500rpm.
External wastegates aren't necessary.
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- #17
Did you read previous posts I am looking in the low A/R which means it will spool quicker lower the A/R. Garrett will build a turbo almost any configuration in the GT series turbos for diesel or gas. I have built a lot of turbo charged diesels and gas. The air/water inter coolers are by far better than air/air and are a lot more compact. I am more worried about not having enough fuel to feed the engine with the stock injection pump. I have thought of using propane because of the cooling affect.
A smaller A/R turbine will certainly spool earlier (as I like it on a diesel), but the price is extra backpressure which will give you less top end power than the same turbo with a bigger exhaust housing.
It depends which goal you'd rather shoot for, a certain power number or lots of usable torque at low rpm.
You mentioned before you'd prefer an HZ over an HD. Why is this?
It's an interesting project you've got planned, that's for sure.
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- #19
I prefer the HZ one the higher compression and I all ready have it. I would like to try the 5.9 12V Cummins I have the dimensions of the engine and have found it it is close to the same size as the HZ. Just about 4-5" taller. If it doesn't work I would like a FJ60 with one in it and I know it will fit in it. I have done lots of fab and I am a Machinist/Millwright by trade. I like challenges and I think this could be one. What turbos do you guys recommend? Thanks
I prefer the HZ one the higher compression and I all ready have it.
That's always the best reason.
The old GT2860 (which is now called a GT2560) would be my choice. Either 0.64 A/R housing for more low end boost or 0.86 A/R for more high end power.
It's been a favourite of the Nissan TD42 guys for a long time. Some are using the GT2860RS (disco potato) but that's bigger than I'd like.