Builds Isuzu 4BD1T Lexus LX450 (Land Cruiser) Build (5 Viewers)

[Wheelingnoob]

1030F EGT isn't much. I run mine to 750C (1380F) without problems. Remember the hotter you go the more efficiently your turbo runs.

Yeah I just always read under continuous load 1100f should be the max. If I can go higher I will, it felt a lot more lively at 1250f. I was also getting 23psi at that temp.

 

[Dougal]

Yeah I just always read under continuous load 1100f should be the max. If I can go higher I will, it felt a lot more lively at 1250f. I was also getting 23psi at that temp.

Crank it up. They run hotter than that stock.
I have seen 900C (1650F) on several occasions (inattention mostly) and my engine survived fine.

 

[Wheelingnoob]

Crank it up. They run hotter than that stock.
I have seen 900C (1650F) on several occasions (inattention mostly) and my engine survived fine.

Noted! I'll turn it up another 1/2 turn.

 

[fabmec]

Yes 750 C (1380 F) is the listed continuous max egt pre turbo for these engines under full load. It can take a good 5 minutes at full load, then a further 15 or more minutes at full load to reach stable peak egt. It just depends on how much load and for what duration as to how far you can push it, but 750 C is safe for this engine.

 

[GLTHFJ60]

I'm up to 1300, sometimes 1350 if I don't pay attention, but agree, don't want to go higher than that. I'm nearly always around 1000*F.

 

[Wheelingnoob]

Thanks guys! I turn it up a bit more then give it a good test in the mountains this weekend. On the way back I'll have a roof top tent adding drag as well.

 

[wrongway around]

man thats hot i never go past 1250 on my hdt , i dont even like that. Does the 4bd1t have all steel inners? hdt's rings lands melt at the temps you guys are running.

 

[gerg]

Hang on a second here. Are you actually serous? They melt? What the Sam Hill are they made of, die cast pot metal or something? I thought 1hdts had steel ring lands? Even my 30yr old 3b can and has done these temps multiple times at WOT for half an hour at a time and has never ever had ring issues. Are they just like the 2h and 12ht?

 

[Dougal]

man thats hot i never go past 1250 on my hdt , i dont even like that. Does the 4bd1t have all steel inners? hdt's rings lands melt at the temps you guys are running.

4BD1T has chromard liners (hard chrome plated steel) and oil squirter cooled alfin pistons which have a (I think) nickel insert reinforcing the piston ring-lands. But this is not much different to other engines. High temp failures are always the piston melting and spreading out to grab the bore.

But I've never heard of any tdi engine being hurt by a true 750C. If you have the probe in a cold spot and get a false low reading then you can melt pistons with whatever you like on the gauge.

 

[gerg]

I always have put my egt gauge in the collector to get an average of all the cylinders, but I think in the future I'll target perhaps the 1st or last runner as they usually get starved for air and would run hotter in my mind. I don't like the idea of not getting an overall temp but mixing the stream will even out even a hot cylinder quite a bit. I certainly don't feel like running multiple probes. Like in the 3b the 1st and 4th for sure get starved as it doesn't even have a plenum to draw from. Or actually, considering there is no plenum, perhaps all the cylinders get equally starved. Lame.

 

[wrongway around]

hmm maby im saying the wrong thing . on the alfin pistons just above the ring the piston melts and gets into the rings and will reshape the side of the piston . not just me ive seen it on a few . in anycase you run them at 1650 i hardly think it would servive. i'll stay at 1200-1250 thanks . ive never seen over1350 ever i'd rather drop a gear and run her past redline. as a matter of fact i have no issues running past redline for a whole tank of diesel if im in a hurry, but high egts scare me. and if your probe is not in the right spot you shouldnt be playing the fueling game. no. 6 seems to be comon one to fail.

 

[Dougal]

hmm maby im saying the wrong thing . on the alfin pistons just above the ring the piston melts and gets into the rings and will reshape the side of the piston . not just me ive seen it on a few . in anycase you run them at 1650 i hardly think it would servive. i'll stay at 1200-1250 thanks . ive never seen over1350 ever i'd rather drop a gear and run her past redline. as a matter of fact i have no issues running past redline for a whole tank of diesel if im in a hurry, but high egts scare me. and if your probe is not in the right spot you shouldnt be playing the fueling game. no. 6 seems to be comon one to fail.

The hottest part of a DI piston is normally the bowl. If your injection timing is retarded you can shift that hottest point to the exhaust valve and melt the crown.

I don't intentionally run mine at 1650F. It's just been there a few times accidentally. Last time I think I was running a bigger turbo, towing a big boat and didn't realise it had slowed down enough to drop some boost.
I do run 750C (1380F) sustained and I recently had the head off which confirmed no thermal damage to pistons.

For me that was conclusive.

 

[gerg]

So I do enjoy the fuelling game usually, except right now it involves filling up my fz every week so it's not as fun. Egt probe at the point where all the runners collect pre turbo isn't what I'd call the wrong spot, but as you said... Number 6 runs hot... So why not use it's temp as the cut off for max egt. In a way we actually agree, it just not as cordial as I'm use to.

 

[sailor]

i do 1350 pre turbo on the snowshed hill every year multiple times in the summer, pulling the trailer with a full load. I think the engine likes it as it is usually much cleaner exhaust wise afterwards for a while. It stays in OD but this year I was down to 85 kmh at the top with no A/C. Last year I was over 100kmh at the top with the A/C on. Before we started playing with the engine it was a 3rd gear 70 kmh ordeal. I use my mark 1 human right foot exhaust temperature modulator to limit at 1350 and see what the speed is from there...

The only issue is if I am forced to slow down on the hill (frickin rental motorhomes!) and get out of my carefully prepared 'climb profile' lol.

 

[Wheelingnoob]

Today I got the PCV catch can installed and plumbed in. Fits great and I hope it works well. I ran the outlet to the pipe that I made to go from filter to turbo. I used the stock oil drain back to the sump. I will seriously enjoy not smelling the crank case gases any longer. We'll see how well it works at removing oil from the vapours.

Almost ready for my 800kms journey, that 2 day drip will double the millage to date on the swap. Hope I have not overlooked anything.

Fortunately I have a friend up there that has a 80 series with a 4bd and some room to work on it if needed.

Tomorrow I'm going to put another 1/2 turn of fuel into it and see how the EGT's are up the snowshed.

 

[sailor]

Good luck!

 

[MatS]

Ya good luck man. Cool temps and rain might help with temperatures

 

[Wheelingnoob]

Ya good luck man. Cool temps and rain might help with temperatures

Yeah I'm leaving the locked fan on for this trip. I had hoped I would have time to try the clutch fan but at this point I have not and will not till I leave on my trip.

Each time recently I have driven it for a long period of time on the hwy the upper rad tank (hot) it's been 168-175f with the IR gun. I'll watch the temp on the coke and check temps at the summit to get an idea how it's working.

 

[mistyv6]

if you can unlock the fan clutch easy , find some flat road unlock fan and see what it does , you should be able to run on flat ground and the air though the rad should keep it cool .

 

[Wheelingnoob]

if you can unlock the fan clutch easy , find some flat road unlock fan and see what it does , you should be able to run on flat ground and the air though the rad should keep it cool .

I can't unlock it easily it's got two large screws through the clutch and a fan swap is not practical with the time I have available.