1HDT maximum efficiency? (1 Viewer)
- Thread starter TZ62
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excellent info. do you have similar graphs for the 13B-T to compare ? on mine the 'sweet spot' is around 2400 rpm which gives 10l/100km at 100kph
I think must have one of these European higher-geared ones, (1993 12v auto, sold in UK originally) as Im showing 1950RPM at an indicated 60mph. Im on 285s so speedo is slightly out, and also, I am having trouble locating the torque converter locking up at all, I get O/D at 40mph pretty much exactly, and if one holds the throttle steady, a little surge forwards as O/D comes in. Ive gotten into the habit of backing off the throttle slightly, to negate the OD lunge forwards and keep it smooth. But continues acceleration produces no more rev drops on the tacho, my butt dyno thinks the Torque converter is locked as OD comes in, could that be possible?
and all this talk of how slow they are has never really been my experience, for a huge heavy beast it always seems to hustle along ok whenever I press the throttle. my other car is an Audi 2.8 cabriolet manual, and is not a slouch, but I rarely over-take anything in that, that I could not also do with a burst of flooring it in the cruiser, albeit the Audi is a lot less dramatic about it. I think different US gearing must really give a whole different driving experience.
I've never wound it up to top speed but I've been up to 80mph in it, and there's definitely much more there, as it's not even at 3000RPM. 80mph seems like an insane speed to drive a big tall wobbly A/T tyred 2 & 1/2 ton battering ram to me though, I rarely get it past 60 in normal use, and that sometimes feels hooligan-like around the reasonably fast bendy country lanes here, with random pedestrians, cyclists, animals, rocks etc liable to challenge you at any point.
PS just saw this on YT - 1HD-T auto bopping along at 195kmh (120mph)
presumably this is not "the slow" you are all complaining about? or do you maybe mean it's just not a super-charged large block v8?
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The A442F is a 3 speed plus OD = 4 speeds. If you have the electronic version (and you should as you're a '93), you'll have an "O/D off" button on the shifter handle, that lets you limit it from upshifting beyond 3rd gear, and it should have 3rd and 4th gear TC lockup. I'm also on 285's, with the speedo corrected (thanks PO!), but mine will lock the TC just before 85km/h(53mph) in either 3rd or 4th gear. It also doesn't shift up to OD until about 80km/h, so when it does it's like a double shift sensation as it shifts to OD and almost immediately locks the TC. My truck has the 4.11 diff gearing, so the numbers might not be the same for you, but try playing around in 3rd (O/D off) and see if you can feel the TC lockup.
thear sres in me hdt 80 i put a little electric valve with a switch the hose of the turbo pressure come to this valve and from this valve for the injection pump boost diaphragm when i like power and no more problem with the cost of the fuel the switch is in the on position when me pockets are empty i put the switch off and the turbo pressure dont move the boost diaphragm and the economy is very good and the power is good , the beast is slipping and my pocket happy
I think must have one of these European higher-geared ones, (1993 12v auto, sold in UK originally) as Im showing 1950RPM at an indicated 60mph. Im on 285s so speedo is slightly out, and also, I am having trouble locating the torque converter locking up at all, I get O/D at 40mph pretty much exactly, and if one holds the throttle steady, a little surge forwards as O/D comes in. Ive gotten into the habit of backing off the throttle slightly, to negate the OD lunge forwards and keep it smooth. But continues acceleration produces no more rev drops on the tacho, my butt dyno thinks the Torque converter is locked as OD comes in, could that be possible?
and all this talk of how slow they are has never really been my experience, for a huge heavy beast it always seems to hustle along ok whenever I press the throttle. my other car is an Audi 2.8 cabriolet manual, and is not a slouch, but I rarely over-take anything in that, that I could not also do with a burst of flooring it in the cruiser, albeit the Audi is a lot less dramatic about it. I think different US gearing must really give a whole different driving experience.
I've never wound it up to top speed but I've been up to 80mph in it, and there's definitely much more there, as it's not even at 3000RPM. 80mph seems like an insane speed to drive a big tall wobbly A/T tyred 2 & 1/2 ton battering ram to me though, I rarely get it past 60 in normal use, and that sometimes feels hooligan-like around the reasonably fast bendy country lanes here, with random pedestrians, cyclists, animals, rocks etc liable to challenge you at any point.
PS just saw this on YT - 1HD-T auto bopping along at 195kmh (120mph)
presumably this is not "the slow" you are all complaining about? or do you maybe mean it's just not a super-charged large block v8?
As far as I know the only Diesel 80’s that came with the 3.73 gears where lhd HDJ80’s with the 5 speed manual transmission.
Tapage
Club 4X4 Panamá
not down here .. all were 4.10
No I think the 3.70’s only came on Euro spec HDJ80’s with a 5 speed
Tapage
Club 4X4 Panamá
makes sense for economy on HW use ..
wouldn't this run too lean then when you are boosting?
I would think so, but the side effects would be down on power, and probably boost would be limited, I'm not sure what you could hurt really.
yes of course the engine run more lean but this is not a problem the egt come down the fuel come down and in the higway when you attach 120 kph the the weight of the land maintain the force
interesting. presumably this would drop the emissions at test time too?
I have been considering replacing a vacuum T piece with a blocked one at test time for the same (temporary) results but a permanently wired valve on a switch would be a better option if there's no danger from actually driving like that occasionally too.
when you make the probe with the blocked t yo must fill a little less of power but is very little but if you use this system for a long period de fuel change to 7,5 a 1 to 9 a1 a good economy
in the same land cruiser you have the valve take a look at the vacuum valve of the air condition when you connect the air codition the engine give more rpm at idle is the same valve i put one of this and open or shut the pressure line to de injection pump diphragm
please take care and excuseme me wrong english i live in uruguay south america the land cruiser 80 series here is a very rare best
please take care and excuseme me wrong english i live in uruguay south america the land cruiser 80 series here is a very rare best
Tapage
Club 4X4 Panamá
I never had 30' so can't tell besides I don't like to run it over 3500 for more than couple of seconds as much only if it's necessary ..
hey dude, would it be possible to get a pic of your valve install? I bought a couple of these and am going to test, this summer, but it has to be invisible, and / or look stock to avoid attention at testing time, just wondering how /where you fitted yours?
dont worry amigo, I did it today. I found some long-ish vacuum tubes on a mates Patrol scrapper and plumbed it in. took her out for a little drive round the block with the solenoid activated, no noticeable difference at normal speeds and driving, but a very noticeable less large and dense belch of smoke on booting it from idle. fingers crossed the emissions testing machine sees the same. many thanks for the suggestion.
edit. pics here if anybody interested
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Hello!
As a happy owner of a 1HD-T with an A442F, I can assure you the best engine speed for economy is 1800RPM...now...how fast you want to go on your cruiser is a different thing...I have clocked mine to 175kph on 275's and at that speed I actually saw the fuel gauge drop...in a manual transmission is a different matter, as a manual will be higher geared than an automatic...at said 1800RPM may cruiser is traveling at 80kph...if I change the tyres for...say...33's it should be doing like 100kph...the thing is what you use it for...in stock form, your manual should reach 100kph like in 2200RPM...try to use a GPS to measure your speed better...
P.S. at 1800RPM my car travels 460kms with half the main tank (got the sub tank stock also) you do the math
P.S.S. at 1400RPM the 1HD-T has top torque, the 1HZ has it at 2200RPM...manual transmission makes it difficult to asses it...H151F has different gears than H150F...R151F used in FZ or HZ has different gears also
As a happy owner of a 1HD-T with an A442F, I can assure you the best engine speed for economy is 1800RPM...now...how fast you want to go on your cruiser is a different thing...I have clocked mine to 175kph on 275's and at that speed I actually saw the fuel gauge drop...in a manual transmission is a different matter, as a manual will be higher geared than an automatic...at said 1800RPM may cruiser is traveling at 80kph...if I change the tyres for...say...33's it should be doing like 100kph...the thing is what you use it for...in stock form, your manual should reach 100kph like in 2200RPM...try to use a GPS to measure your speed better...
P.S. at 1800RPM my car travels 460kms with half the main tank (got the sub tank stock also) you do the math
P.S.S. at 1400RPM the 1HD-T has top torque, the 1HZ has it at 2200RPM...manual transmission makes it difficult to asses it...H151F has different gears than H150F...R151F used in FZ or HZ has different gears also
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