12H-T performance Build
- Thread starter gbentink
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- Thread starter
- #142
OK, Fair enough on the doubters, no problem.
As an update, a friend of mine has bought the engine unassembled (I have started assembly, well, cam tunnel bearings are installed and the owner is currently painting the block) and I hope to start the major build within 2 weeks, so, this means the engine should be installed at ~ end of month. I am really looking forward to it.
Since it will be a daily driver and required immediately, it will have a 3" exhaust fitted, intercooelr and 18psi using initially a std CT26 but eventually a Supra comprtessor wheel. I would like to do the twin turbo for him, but it is a time consuming excercise, expensive and unproven, so not something I would sell to a friend. having said that, I am very sure my setup was ideal.
It will be a nice engine on the manual and will be setup to rev a bit higher and have a flatter torque curve than std - so will feel even revier.
The clutch to be fitted is far stronger than stock, so hopefully it holds. I dont expect 600nm given we are going for no smoke option,, but I do think low to mid 500 is achievable given the boost level.
I will let hime do his own thread though, but I will talk to him about dynoing it. I will do a bGtech before and after anyway, it has proven very accurate in the past.
Clint if you are reading this, please remind me. should expect ~ 65-70rwkw stock.
As an update, a friend of mine has bought the engine unassembled (I have started assembly, well, cam tunnel bearings are installed and the owner is currently painting the block) and I hope to start the major build within 2 weeks, so, this means the engine should be installed at ~ end of month. I am really looking forward to it.
Since it will be a daily driver and required immediately, it will have a 3" exhaust fitted, intercooelr and 18psi using initially a std CT26 but eventually a Supra comprtessor wheel. I would like to do the twin turbo for him, but it is a time consuming excercise, expensive and unproven, so not something I would sell to a friend. having said that, I am very sure my setup was ideal.
It will be a nice engine on the manual and will be setup to rev a bit higher and have a flatter torque curve than std - so will feel even revier.
The clutch to be fitted is far stronger than stock, so hopefully it holds. I dont expect 600nm given we are going for no smoke option,, but I do think low to mid 500 is achievable given the boost level.
I will let hime do his own thread though, but I will talk to him about dynoing it. I will do a bGtech before and after anyway, it has proven very accurate in the past.
Clint if you are reading this, please remind me. should expect ~ 65-70rwkw stock.
- Thread starter
- #143
Blis, this is the ONLY response I have seen on the actual pump specs. 9mm is huge! I figured on 7mm!
Do you know any more about the pumps, could you elaborate on your experience, I am supremely interested on any useful data.
Dougal, thanks for the calc, 670nm based on 240gms/kwh....impressive, maybe another 10% lurking in there!
My build once the current engine is up and running will be near on 4.93 liters running a huge VNT turbo. It is PROVEN on a 4.2L and there is no doubt about it being a top setup, but isnt twin turbo. So, sorry to those following the twin arrangment (will look at it again later), but I still hope to be able to give some useful feedback on other interesting mods. Surely 4.93 running up to 3.5Bar is still interesting? Turbo should deliver from 1800rpm and up (theory). I know it boosted well over 20psi from under 2000rpm on a 4.2. Not sure what it boosted, but delivered chasis twisting torque and all smoke dissappeared!
If I can get clean 670nm, I will be totally stoked. Best news I have had in ages is 110cc on std pump!!!!!!
Question is can the auto handle it ?!?!?! I plan to find out.
Do you know any more about the pumps, could you elaborate on your experience, I am supremely interested on any useful data.
Dougal, thanks for the calc, 670nm based on 240gms/kwh....impressive, maybe another 10% lurking in there!
My build once the current engine is up and running will be near on 4.93 liters running a huge VNT turbo. It is PROVEN on a 4.2L and there is no doubt about it being a top setup, but isnt twin turbo. So, sorry to those following the twin arrangment (will look at it again later), but I still hope to be able to give some useful feedback on other interesting mods. Surely 4.93 running up to 3.5Bar is still interesting? Turbo should deliver from 1800rpm and up (theory). I know it boosted well over 20psi from under 2000rpm on a 4.2. Not sure what it boosted, but delivered chasis twisting torque and all smoke dissappeared!
If I can get clean 670nm, I will be totally stoked. Best news I have had in ages is 110cc on std pump!!!!!!
Question is can the auto handle it ?!?!?! I plan to find out.
- Thread starter
- #144
Another thing to consider with increased boost is injector cracking pressure, which should be set a fair amount higher if running big boost. All the factory engines that are DI and run ~ 30psi std seem to have pressures increased from factory 190-200 Bar to 230-240 Bar. When I run a basic cylinder pressure calc at TDC no combustion, it appears about the expected difference required to maintain the same pressure difference across the injector.
- Thread starter
- #145
yet another comment....
I plan to play around with my HJ61 over the coming months (head goes on tonight - all manifolds on, injectors cleaned and on and lines all cleaned out). I have decided water to air ONLY because of the high boost and going this route limits joins - all joins are potential leaks.
So, the HJ61 will be an intercooler test mule for me - one less thing to do later. One major issue I find is when I make a heap of changes, I usually have to put out a heap of fires... better to minimize changes and isolate the issues....
I note the 12HT has an inlet manifold design that does not appear to lend itself to high boost without blowing out the rubber gasket. This is a theory, but.... seems that way to me. I have not determined a solution yet (or determined that a solution is actually required).
I plan to play around with my HJ61 over the coming months (head goes on tonight - all manifolds on, injectors cleaned and on and lines all cleaned out). I have decided water to air ONLY because of the high boost and going this route limits joins - all joins are potential leaks.
So, the HJ61 will be an intercooler test mule for me - one less thing to do later. One major issue I find is when I make a heap of changes, I usually have to put out a heap of fires... better to minimize changes and isolate the issues....
I note the 12HT has an inlet manifold design that does not appear to lend itself to high boost without blowing out the rubber gasket. This is a theory, but.... seems that way to me. I have not determined a solution yet (or determined that a solution is actually required).
as long as you can keep it cool ... I don't see a problem there ..
- Thread starter
- #147
Hi Tapage, the problem isnt the heat - I am a believer in having the TC locked up at all times other than sub 60km/hr in high range (~ 26km/h low range).
The problem I fear is slippage of the clutches. The A442F (an improved A440F) in my HDJ81 that had been rebuilt, would not hold 600nm without slipping when locked up. I do not know what clutch was slipping - most likely the lockup clutch. It held 550nm not problem though
BTW: Anyone heard of a broken 12HT Conrod because of too much fuel?
The problem I fear is slippage of the clutches. The A442F (an improved A440F) in my HDJ81 that had been rebuilt, would not hold 600nm without slipping when locked up. I do not know what clutch was slipping - most likely the lockup clutch. It held 550nm not problem though
BTW: Anyone heard of a broken 12HT Conrod because of too much fuel?
i have a question on the a440f. has anyone done a full manual shift conversion on one? i got one a while ago, mainly for the lower low range transfer case, but if this is possible i will use it behind my 12ht. when i eventually get round to putting it in
oh yeah, a 12ht boosted up to 50psi would be nuts!
oh yeah, a 12ht boosted up to 50psi would be nuts!
- Thread starter
- #149
You can change them manually anyway, so auto is always an option.
What is of supreme benefit is getting the torque converter locked up at ~ 60km/hr in 4th and ensuring 3rd can be locked up. The early A442F and of course the A440F did not lock up in 3rd. This is the main reason so many boxes died an early death. People would tow in 3rd and a huge amount of heat would be generated and the factory cooling could not manage to remove enough of the heat.
What is of supreme benefit is getting the torque converter locked up at ~ 60km/hr in 4th and ensuring 3rd can be locked up. The early A442F and of course the A440F did not lock up in 3rd. This is the main reason so many boxes died an early death. People would tow in 3rd and a huge amount of heat would be generated and the factory cooling could not manage to remove enough of the heat.
- Thread starter
- #150
A MILESTONE REACHED
I started up the 12HT in my HJ61 yesterday; minus turbo and cooling fluid, just to check it worked and that there were no oil leaks.
Runs like a beauty. I did have a small mishap with poor running when I first started it. because I had replaced the lifters and not checked the valve clearances (they would have been fine for the old lifters), i was down on compression on No.4. I initially thought I had installed a dodgy injector. I happen to have loan of an injector tester, so I pulled them all out and tested them to be fine (200-210 Bar, nice chatter and nice spray pattern) and went back and checked valve clearances. Anyway, after doing that it sounds great mechanically - just really loud without the turbo.
I started rebuilding a turbo last night, but small changes between models of CT26 that I have meant that the ex housing wouldnt bolt on without touching the turbine....... I was not aware that there were slight variations in gemoetry between models on the inside - and I have pulled heaps apart. Anyway, I will grab another turbine and all will be good! Oh well, looks like I wont be able to use my high flow turbine in this one! I had back cut it for the twin turbo setup and thought it would be good to see if there was any change in spool in the smaller auto housing - the auto housing chokes up top a bit so I figured it would be an interesting experiment.
I have bought a water to air intercooler and plan to fit that in order to be ready to bolt directly on to the performance build motor, when that is complete. I *may* also fit a 3" exhaust system to my HJ61. I kind of dont want too because I am not planning on keeping the vehicle, but tempting to get it all tuned up just the same!
So far so good - all good experience so that when the next motor is done, all will be quicker. Knowing what needs to be bolted on before something else is a bonus. The way the Aircon appears to have been added on as an afterthought is a classic! But, so long as you know that the fan needs to be off to gain access to the bolts for the aircon belt tension idler pulley, all is good!! I had forgotten that...anyway, only cost be a few minutes.
I started up the 12HT in my HJ61 yesterday; minus turbo and cooling fluid, just to check it worked and that there were no oil leaks.
Runs like a beauty. I did have a small mishap with poor running when I first started it. because I had replaced the lifters and not checked the valve clearances (they would have been fine for the old lifters), i was down on compression on No.4. I initially thought I had installed a dodgy injector. I happen to have loan of an injector tester, so I pulled them all out and tested them to be fine (200-210 Bar, nice chatter and nice spray pattern) and went back and checked valve clearances. Anyway, after doing that it sounds great mechanically - just really loud without the turbo.
I started rebuilding a turbo last night, but small changes between models of CT26 that I have meant that the ex housing wouldnt bolt on without touching the turbine....... I was not aware that there were slight variations in gemoetry between models on the inside - and I have pulled heaps apart. Anyway, I will grab another turbine and all will be good! Oh well, looks like I wont be able to use my high flow turbine in this one! I had back cut it for the twin turbo setup and thought it would be good to see if there was any change in spool in the smaller auto housing - the auto housing chokes up top a bit so I figured it would be an interesting experiment.
I have bought a water to air intercooler and plan to fit that in order to be ready to bolt directly on to the performance build motor, when that is complete. I *may* also fit a 3" exhaust system to my HJ61. I kind of dont want too because I am not planning on keeping the vehicle, but tempting to get it all tuned up just the same!
So far so good - all good experience so that when the next motor is done, all will be quicker. Knowing what needs to be bolted on before something else is a bonus. The way the Aircon appears to have been added on as an afterthought is a classic! But, so long as you know that the fan needs to be off to gain access to the bolts for the aircon belt tension idler pulley, all is good!! I had forgotten that...anyway, only cost be a few minutes.
gbentink said:You can change them manually anyway, so auto is always an option.
by this do you mean you can make it hold a gear until you tell it to change? how would you signal it to change?
sorry about the hijack. looking forward to the stroker 12ht build up
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- #153
Quote: by this do you mean you can make it hold a gear until you tell it to change? how would you signal it to change?
sorry about the hijack. looking forward to the stroker 12ht build up
Easy, move the gear shift......
OK, HJ61 all up and running and yes I am planning to sell it. It will be sufficient as a test mule for add ons until my 80 series BIG12HT is done.
OK, it goes really well, boost is north of 15psi. I havent installed any gauges, which is unlike me. I usually check EBP, IMP and EGT.... This time, smoke is the measurement.
I estimate ~ 160 flywheel HP at the moment. I will test it soon enough and let you know rwhp. It revs really well, with urgency hard to 3800 no problem. 15psi @ 2000rpm with modded turbo which is better than what I expected!
Pics of exhaust turbine mods attached - I did the mods, shape change should be evident. Was balanced before I put it back on, obviously.
Exhaust is hugely restricted and needs to be changed, has a huge "whoosh" out the exhaust when you get to 2200rpm......
Engine runs like a dream, sounds totally old school truck like, very even, no smoke at any time except start up and while warming up at idle it has slight black tinge.
sorry about the hijack. looking forward to the stroker 12ht build up
Easy, move the gear shift......
OK, HJ61 all up and running and yes I am planning to sell it. It will be sufficient as a test mule for add ons until my 80 series BIG12HT is done.
OK, it goes really well, boost is north of 15psi. I havent installed any gauges, which is unlike me. I usually check EBP, IMP and EGT.... This time, smoke is the measurement.
I estimate ~ 160 flywheel HP at the moment. I will test it soon enough and let you know rwhp. It revs really well, with urgency hard to 3800 no problem. 15psi @ 2000rpm with modded turbo which is better than what I expected!
Pics of exhaust turbine mods attached - I did the mods, shape change should be evident. Was balanced before I put it back on, obviously.
Exhaust is hugely restricted and needs to be changed, has a huge "whoosh" out the exhaust when you get to 2200rpm......
Engine runs like a dream, sounds totally old school truck like, very even, no smoke at any time except start up and while warming up at idle it has slight black tinge.
- Thread starter
- #154
Anyone had a stuck oil pressure relief valve? Mine is off the scal most of the time....I am confident it is stuck.
I will have to look up the manual and see how to disassemble, hopefully it is easy to access !!!
It was doing this before the build. I did the engine "in situ" so only changed big end bearings, pistons, rings, lifters and reconditioned the turbo and head. Main will do a million kms and everything else is fine - zero fluid leaks!!
I will have to look up the manual and see how to disassemble, hopefully it is easy to access !!!
It was doing this before the build. I did the engine "in situ" so only changed big end bearings, pistons, rings, lifters and reconditioned the turbo and head. Main will do a million kms and everything else is fine - zero fluid leaks!!
"Easy, move the gear shift......"
yeah i had a look in the manual and saw the shifter positions
. never seen the auto stick before. but i was thinking more of a sequential shift setup anyway, where you pull the shifter back to shift up and push it to shift down. i'm guessing no one has done that to a toyota auto before?
"yeah i had a look in the manual and saw the shifter positions
. never seen the auto stick before. but i was thinking more of a sequential shift setup anyway, where you pull the shifter back to shift up and push it to shift down. i'm guessing no one has done that to a toyota auto before?- Thread starter
- #156
yes, actually it has been done, but must be electronic box and use "Suprastick" ecu. It uses the factory cruise control lever for the shifts. I plan to do this on mine, since it has factory cruise control.
A440F is a hydraulic box, as is pre 92 A442F, so no option there for what you are looking for. I checked with Rodney @ Wholesale Automatics if the A442F electronic valve body can bolt to A440F box - nope....
A440F is a hydraulic box, as is pre 92 A442F, so no option there for what you are looking for. I checked with Rodney @ Wholesale Automatics if the A442F electronic valve body can bolt to A440F box - nope....
oh well, spose i could get use to using the shifter to change gears. was talking to a friend who is into V8s before i got the auto box and he said with the chev hydraulic autos it involves drilling out the valve body to make it a manual shift. don't really want to be a guinea pig for that sort of thing
- Thread starter
- #159
OK, will do a video within the next month. I would like to do a better exhaust system first, mine is probably worse than stock........ But, I could video how quick it accelerates to 100km/h.......