See if u can get a better pic of the blue circled thingy
Its definetly not standard
Its definetly not standard
Diesel newbie thinks 12H-T is underpowered - help needed
- Thread starter TLink FJ60
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Really? Are you saying air pressure varies significantly at different locations between the turbo and the intake valves? That seems surprising to me, and not likely, but sure could be true.
Im by no means an expert but my thinking is as the turbo builds boost pressure there would be a difference in pressure at the turbo compared to at the intake manifold. isnt this what lag is?
without an intercooler theres going to be bugger all if any difference
If there is an intercooler in between, ya there will be a pressure difference.
Just to compare power, I drove my unturboed 1HZ up a 5.8 klm hill with a 7.3% gradient last sunday. It did it in 4th gear with ease and power to spare at 80kph. Not much to spare but the engine was comfortable with it.
I did the same hill in a Dyna with a new pump and injectors a few years back ,and I think I was in second gear half way up and slowing.
I did the same hill in a Dyna with a new pump and injectors a few years back ,and I think I was in second gear half way up and slowing.
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- Thread starter
- #47
Sorry, not familiar with Dyna's. What engine do they run? Are you comparing 1HZ to 12HT or are you comparing same engine in two different rigs? Either way, I'm certain my 12HT would be struggling on that 7.3% grade.
Gauges should arrive tomorrow. I'll have more info soon.
DanS HJ-45
SILVER Star
That's very different than my experience.
We can drive up Raton Pass at 55mph comfortably. I was doing about 35 in the FJ-60.
It's definitely going to be more pronounced up here at altitude, since the 2F is normally aspirated and the 12HT obviously isn't, but they aren't remotely the same. The 12HT feels like a hotrod to me. The fact that it can pass cars legitimately is pretty amazing to me.
Dan
When i drive my naturally aspirated 2H it slows down before i even get to the hill....so i just cover the headlights so she cant see the hills....problem solvered! lol
Sorry ,this old Dyna had a 3B They used to have the same engines as Landcruisers up until 1989 or so.
I wonder if your boost compensator is jammed? I picked up a HJ61 some years back and drove it 300kms home and it really sucked for power , infact I put up a post here about it at the time and said the exact same thing you did "it felt like it didn't have a turbo" . I only recently started playing with my pump on my 12HT on my 70 and went to this spare engine to pull things apart first to see if I could try and make sense of these inline pumps. I discovered , I have no idea how, that the boost compensator was jammed , well jammed. It somehow locked itself up inside the governor. I unjammed it and it moved freely again , it was all factory safety wired shut too so nobody had been playing with it. I haven't run it since but Im pretty sure that was affecting its lack of power , maybe pull the cover off your boost compensator at the back of your pump and see if it can move freely? would only take 5 mins. Also while your there , check the compensators feed line has vaccum when running. The difference of it not is quite impressive.
Keep at it. I G-Turbo'd my 12HT and played with the pump abit and now it seriously hauls arse. It s***s all over my FJ73
Keep at it. I G-Turbo'd my 12HT and played with the pump abit and now it seriously hauls arse. It s***s all over my FJ73
While not a race car, my HJ-61 pulls hills without issues. Driving unloaded without any heavy armor through PA with 31"s, 4.11's, and H55; she would accelerate up the hills in 5th with authority. It gave me giggles compared to the tired 2F I've been used to.
There isn't a noticeable turbo whine even when the green light is on.
There isn't a noticeable turbo whine even when the green light is on.
- Thread starter
- #53
As suggested by above posts and several others, I have installed boost and EGT gauges. I still have a lot of things on the list to work through, but I have some preliminary numbers...I need to come up with a more scientific approach and get out on a stretch of road where I can drive consistently...
Boost
while moderately accelerating through the gears:
1300-1600 rpms 1-3 psi
1600-2100 rpms 3-7 psi
2100+ 7psi
The only thing I'm certain about is that the max is 7psi. I'll get better numbers vs rpms soon.
EGT:
with consistent speed/ flat ground/ little load
35-45 mph (~55-70 kph) > 450 F (235 C)
55 mph (90 kph) > 650 F (345 C)
pedal mashed for 30-60 sec on slight incline
65 mph (105 kph) > 800 F (425 C)
The Max I have achieved is about 850 F (455 C)
So... what is the initial reaction to these numbers? What tests should I perform? What numbers do we need to compare:
boost vs egt? boost vs rpm? egt vs rpm? flat ground? loaded on a hill? at top speed? low end acceleration?
Your boost is low because your EGT is low. Your EGT is low because something is restricting fuel.
I'd look at boost compensators (I don't know the details), fuel filters and injection pump adjustment. You need to get EGT up to around 650C minimum under sustained full load (not necessarily full revs).
Agreed. Egts way too low for full throttle. Look to the pump
DanS HJ-45
SILVER Star
Wholeheartedly agree: your EGTs are low.
Our 12HT doesn't make more than 7 lbs of boost either, but it will get to 1200 (F) EGT on a moderately long incline. 850 is about where it cruises on level ground (or even a slight incline) at 65mph, but any hill of consequence and it jumps to 1000 pretty quick.
That would be in 5th gear for us. Maybe tomorrow I'll see if I can't take a video for you of our EGTs and acceleration, etc...
Dan
Our 12HT doesn't make more than 7 lbs of boost either, but it will get to 1200 (F) EGT on a moderately long incline. 850 is about where it cruises on level ground (or even a slight incline) at 65mph, but any hill of consequence and it jumps to 1000 pretty quick.
That would be in 5th gear for us. Maybe tomorrow I'll see if I can't take a video for you of our EGTs and acceleration, etc...
Dan
The manual says to test the fuel delivery by revving it to 4300 in neutral to see if ti can do it. I forget the exact rpm figure it varies 150 or so rpm between auto and manuals, but its over 4200
OP,
I have the Exact(same graphics, year, color, and almost identical mileage) truck as yours. I am located in Colorado and picked the truck up 6 months ago. Since then I've driven over 14,000 miles all in extremely mountainous terrain and we live at 7500 ft.
I drive up and over Eisenhower Tunnel or Loveland Pass on a weekly basis each of which is at 12,000 ft or higher.
I too was a little disappointed with the power.
BUT!
I just had a 3" straight pipe exhaust welded on from the dump pipe all the way back exiting out the rear. Then I added a Manual Boost Controller from Hallman. (I already had gauges installed)
HOLY BATMAN!
The whole truck came to life! The whole winter I heard such little turbo whine and hills were a complete bore. (Slow, scary, even very scary!)
Once I added a manual boost controller it's been awesome, I even got my first speeding warning!
(Since my dog was sitting shotgun or on the left, the cop just chuckled and sent me on my way)
100% make it a priority to add those two things!
GO straight pipe first(you can always add a non-restrictive muffler to quite it down later). Then MBC.
I have the Exact(same graphics, year, color, and almost identical mileage) truck as yours. I am located in Colorado and picked the truck up 6 months ago. Since then I've driven over 14,000 miles all in extremely mountainous terrain and we live at 7500 ft.
I drive up and over Eisenhower Tunnel or Loveland Pass on a weekly basis each of which is at 12,000 ft or higher.
I too was a little disappointed with the power.
BUT!
I just had a 3" straight pipe exhaust welded on from the dump pipe all the way back exiting out the rear. Then I added a Manual Boost Controller from Hallman. (I already had gauges installed)
HOLY BATMAN!
The whole truck came to life! The whole winter I heard such little turbo whine and hills were a complete bore. (Slow, scary, even very scary!)
Once I added a manual boost controller it's been awesome, I even got my first speeding warning!
(Since my dog was sitting shotgun or on the left, the cop just chuckled and sent me on my way)100% make it a priority to add those two things!
GO straight pipe first(you can always add a non-restrictive muffler to quite it down later). Then MBC.
Lots of good advice here and now that you have boost and pyro gauge giving the information needed you can move forward with knowledge.
The following is my experience with BJ74's and HJ61's in stock trim. I mention this so you have more info, however you seem to have something else going on. As has been mentioned, with your numbers, it sounds like it is not getting enough fuel for some reason. Perhaps either your boost compensator is not working, or the fuel has been dialed back for some reason. But 1st...find a really long hill that will work it. See how high your EGT's will get under sustained load (but back off when appropriate).
With both an HJ61 and BJ74 (and same experience for friends with either) I have noticed a few consistencies:
Factory turbo settings are very sedate. Factory exhaust are very restrictive. It's usually a shock and surprise when all is in factory trim and a pyro is hooked up. As in...without knowing, it is very easy to get into the danger zone when under any load. I usually joke around that adding gauges is the worst thing to do as it usually makes driving style more sedate: Being oblivious is bliss.
I played around with both trucks once I had guages and a baseline:
1) Adding a boost controller or shimming out the wastegate spring pot 4-6mm with washers so your boost is maxed at 10-12 PSI will do wonders.
2) Going to a 2.5" or 3" exhaust lets the engine breathe. I went 2.5" on both of mine with a 2525 AeroTurbine muffler.
Doing both these things (and not touching fuel settings) increased responsiveness, brought down EGT's on both trucks and made it so we had to work it harder to get into the danger zone (used the same hills on a local freeway to compare); As opposed to getting into the danger zone with factory boost and factory exhaust very easily.
In regards to that container that is plumbed in post air filter and pre turbo...on occasion I have seen trucks come over that have a container plumbed in and the only thing I can figure is it's some venturi effect setup that delivers something into the intake air stream. Can you take a picture of the writing so someone might be able to translate?
hth's
gb
The following is my experience with BJ74's and HJ61's in stock trim. I mention this so you have more info, however you seem to have something else going on. As has been mentioned, with your numbers, it sounds like it is not getting enough fuel for some reason. Perhaps either your boost compensator is not working, or the fuel has been dialed back for some reason. But 1st...find a really long hill that will work it. See how high your EGT's will get under sustained load (but back off when appropriate).
With both an HJ61 and BJ74 (and same experience for friends with either) I have noticed a few consistencies:
Factory turbo settings are very sedate. Factory exhaust are very restrictive. It's usually a shock and surprise when all is in factory trim and a pyro is hooked up. As in...without knowing, it is very easy to get into the danger zone when under any load. I usually joke around that adding gauges is the worst thing to do as it usually makes driving style more sedate: Being oblivious is bliss.
I played around with both trucks once I had guages and a baseline:
1) Adding a boost controller or shimming out the wastegate spring pot 4-6mm with washers so your boost is maxed at 10-12 PSI will do wonders.
2) Going to a 2.5" or 3" exhaust lets the engine breathe. I went 2.5" on both of mine with a 2525 AeroTurbine muffler.
Doing both these things (and not touching fuel settings) increased responsiveness, brought down EGT's on both trucks and made it so we had to work it harder to get into the danger zone (used the same hills on a local freeway to compare); As opposed to getting into the danger zone with factory boost and factory exhaust very easily.
In regards to that container that is plumbed in post air filter and pre turbo...on occasion I have seen trucks come over that have a container plumbed in and the only thing I can figure is it's some venturi effect setup that delivers something into the intake air stream. Can you take a picture of the writing so someone might be able to translate?
hth's
gb
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- Thread starter
- #60
Everyone, thanks so much for your help. I'm so glad you guys are here. I have lots of paths to probe at this point. I am certain based on what everyone has said, (with numbers to validate) that my rig is not behaving well. Can't wait to figure out what it is. The upside is that I can achieve more than what I'm currently experiencing.
lisponger, I really love the look of that color and graphics. So fun to drive around - even if I'm slow.
lisponer & Dan, I will be in Colorado 3 separate times over the next 4 months. Any chance I could take your 12HT for a spin? I think driving another one would really give me a sense of what I am looking for - even if gearing, tires etc are different. I'll be driving right past Idaho Springs (in a rental) Wed 4/29 sometime between 4 and 7pm. No worries if it doesn't work out, but pizza and beer are on me.
