LOL, Too bloody true. Probably melted the end off it.


In fun, mate



Follow along with the video below to see how to install our site as a web app on your home screen.
Note: This feature may not be available in some browsers.
This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.
first off, yes, he will be sacrificing bottom end turbo action but then a 1HZ has very good bottom end grunt.
X2 that will compensate or at least help the low end powa ..
Ya, in the course of a second that truck goes from idle to 5000+ rpm, so he has power when he wants it. That truck was in second gear low when he was on the throttle.
l grew up in Limbang Sarawak.now l live in Winnipeg,Canada.
nice truck you have there.
Do you know which shop in KK who can modify and tune injection pumps?
Is Labuan still a free port??
Simon Liew
93 HDJ81
92 HDJ81
92 HZJ77 sold
88 HJ61 sold
92 prado
83 BJ42 waiting for resto
81 BJ42 rockrawler
97 HZJ75 project rockrawler
M101
97 E350 powerstroke tow vehicle.
ARB dealer
TLC import
HI YES we did it long time ago ,running at 32psi with fuel pump upgrade & bunch of other stuft to it with stock internal,on hdj81, taken of seats,carpets,spare tire &bumpers frt & rear , 1/4 mile= 13.5 sec flat.hmm.. It would be interesting to know what kind of power it makes at 30psi.. but before i get there will try do it in 2psi at a time until i reach 30issh.. So far the engine holds up pretty well in terms of temperature and all.. So i'll keep u guys posted once I got there.. I dont have a dyno nearby and the closes one is about 150km away.. I'll do a dyno when i get the time to go on a trip down to the shop.. it would be interesting to know what is the power level at 23psi and 30psi..
But anyway for the current power level when i were using a stock size tyre it would smoke the tyre easily in 2nd.. now i'm running 35s and sometimes if u gas at it hard during a take off at turns it breaks the traction a bit too.. But I'm afraid of doing it too much and stressing to the drivetrain..![]()
Nick
HI YES we did it long time ago ,running at 32psi with fuel pump upgrade & bunch of other stuft to it with stock internal,on hdj81, taken of seats,carpets,spare tire &bumpers frt & rear , 1/4 mile= 13.5 sec flat.
have fun but increase it 1 step at a time , ok
so back to how much boost can a 1hz-t handle that is properly tuned?
would 15 psi with a proper intercooler and tune be fine for longevity.
What are people thinking?
If you want to run 20-24psi on a 1HZ, you'll have more issues than just head bolts.
I did the calcs a while back, but essentially 35psi boost on a 18:1 engine was giving similar compression pressure to 18psi on a 21:1 engine.
It will be cheaper, easier and give a far better result to just find a 1HD-T than build a 1 HZ to handle decent boost.
The lower efficiency of the 1HZ also means a lot less power and torque for the same fuel and boost.
4BD1T's don't need any internal stengthening work unless you're into custom injection pump territory.
There are three factors involved with power output and engine stress.
1. Fuel.
2. Boost.
3. Injection timing.
Boost alone doesn't kill an engine. But boost gives you the ability to burn lots more fuel.
Injection timing is what finally determines where peak combustion pressure occurs and how high that pressure peak is.
Gerg is running high boost on his 3B. But the 3B pump can't put out horrendous amounts of fuel. The 3B also historically appears to survive better turbocharged than the 1HZ.
I'm not sure where Zoltan is at, it's been years since I followed that build. Early power was low for the boost he was running. This does keep EGT's down, but the lower efficiency of the 1HZ's means they do need a lot of boost and fuel to produce not such spectacular numbers.
The TD42's even more so. But their pistons and heads appear much stronger than 1HZ items.
The ford IDI guys in the US intentionally retard timing at higher power levels to reduce peak combustion pressures and keep their engine together. Fuel economy suffers as a direct result.
If you want to compare a 1HZ+T and a 1HD-T at the same fuel and boost levels, the 1HD-T we'd expect to produce 20% more power and torque. Along with less heat rejection to the cooling system.
Comparing a 1HZ+T and 1HD-FT we'd expect about 30% more power and torque from the FT at the same fuelling, but the FT wouldn't need the same boost.
We've got one member on here still sorting out a 1HZ+T from a piston melt and another new member on here who's just found terrible compression on his 1HZ+T.
IMO if you want to build a diesel for lots of power and torque then you need the following:
1. Direct injection compression ratios. (18:1, not 22:1)
2. Direct injection efficiency. (210-230 g/kwh, not 300g/kwh)
3. Direct injection head strength. (no precups in the way)
4. Alfin pistons with reinforced ring-lands
5. Piston squirters.
6. Decent bottom end.
The 1HZ doesn't score well on that list.
More info on 1HZ limitations in this thread: https://forum.ih8mud.com/diesel-tech-24-volts-systems/645879-1hd-t-ls1.html
There are several people I know of who have run high boost (25psi) but also high AFRs (~21:1 which is high for an idi) and low EGTS (450C full load) without issue - even in racing environments.
On the other hand, 12psi and 17:1 will kill them.
I am fairly confident I will have a 250-300whp 1HZ (stock, except the thicker crown coated aftermarket pistons now available, and 1HDT rods) running 35-40psi ~ 18.5:1. Cooling to the head will be enhanced. Intercooling will be as good as I can get it.
Haha, yes actually, but now it looks like it won't happen :-( My brother is all bummed out about the money he's spent on the race car that he is thinking of parting it out or selling it! So there goes the diesel idea - shame, I had sponsors lined up and everything.
Yesterday I was talking to Darren at "Autpocraft" in melbourne. He works on Landcruisers a lot. He said that 1HZ cranks may be cast...... Suggested the surface quality suggested a difference and he has seen broken cranks (he also said that the new V8 diesel is breaking of 1 and 2 cyls at the rank when injectors go bad and uneven torque between cylinders. He's got probably 5 cruisers on the go at any one time, so see's a lot.
So... I had been of the opinion the cranks were the same quality/simply the same, however perhaps they are not?
If you can find a 1HDT, buy that instead would be my advice - they are a performance engine waiting for someone to bolt a good turbo to and tune.