12H-T performance Build

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gbentink said:
CT26 from 7MGTE.

I understood that the manual 1HDT had a larger housing. I could be wrong on this because I has since discovered the 12HT has the same housing on both auoto and manual.

I have been lead to believe that the 1HDFT had a bigger AR exhaust housing. After driving it, I believe it.
Click to expand...

I dont know if your right or not. Looking at my manual 1hd-t housing beside the 7MGTE housing 1hd-t looks a lot smaller.

May not be definitive but this lists OEM model applications for ct 26.

http://www.melett.com/turbo-parts-catalogue/toyota/Toyota-crossref.pdf

I havent heard anything about differences in auto vs manual housings.
I think you are right about the 1HDFT

are you using the 7MGTE turbine housing?
 
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Hi Dougal, be any colour you like. This is true information, I am not asking you whether you think it was possible or not, it would be pointless, I was there. I have also stated that I do not know what boost it was running, I am confident it was at least 30psi.

It was NOT good under about 1750rpm and that is exactly what I see when I look at the compressor curve.

The engine was a Nissan TD42. It was actually Dynoed at 115kw @ 2000rpm @ wheel on mud 35" tyres. Zero smoke. My Brother was really annoyed, he was shooting for over 150kw, preferably 200kw @ wheels. In the end power dropped off after 2400rpm - fuel governer.

I could make the turbo do 1 psi at idle, probably with 10psi backpressure, but such is the adjustment control. In fact I could almost shut the engine off with backpressure if that was the aim.

I forgot yours was 3.9L, that is a big 4cyl. All the same, I would like to see you squeel all the way through second to third with 35" tyres in the dry with a good LSD. I have that on video.
 
No, I have tried the 7MGTE housing. No boost until after 2000rpm and nothing special until after 2500rpm at least. No good for our engines.

Use your std exhaust housing, fit the supra compressor
 
gbentink said:
Hi Dougal, be any colour you like. This is true information, I am not asking you whether you think it was possible or not, it would be pointless, I was there. I have also stated that I do not know what boost it was running, I am confident it was at least 30psi.

It was NOT good under about 1750rpm and that is exactly what I see when I look at the compressor curve.

The engine was a Nissan TD42. It was actually Dynoed at 115kw @ 2000rpm @ wheel on mud 35" tyres. Zero smoke. My Brother was really annoyed, he was shooting for over 150kw, preferably 200kw @ wheels. In the end power dropped off after 2400rpm - fuel governer.

I could make the turbo do 1 psi at idle, probably with 10psi backpressure, but such is the adjustment control. In fact I could almost shut the engine off with backpressure if that was the aim.

I forgot yours was 3.9L, that is a big 4cyl. All the same, I would like to see you squeel all the way through second to third with 35" tyres in the dry with a good LSD. I have that on video.
Click to expand...

Do you have a copy of the dyno chart by any chance?

Squealing 35's in 2wd doesn't take much power. 80kw at the ground would do it at 50km/h. Assumptions being 1 ton on that axle and dynamic friction of 0.6. The size of the tyre doesn't change the power, only the gearing. I don't have 35's, without patrol size diff heads the ground clearance isn't such a problem.

Regardless. Isn't this thread about the 12ht? A turbo with an 82mm compressor wheel isn't a good match for that engine. You get far better results running against the choke line than against the surge line.
The 7.3L Ford Powerstroke ran a GT3782V.
http://www.turbomaster.info/eng/catalogs/model.php?base=garrett&pagina=GT37V
 
Here is the air consumption of a 4L engine at 100% VE plotted on the 82mm, 52 trim compressor map (the red one in there).

At 2000rpm, the air consumption line is still left of the surge line. Remember this is plotted at 100% VE, at a more realistic 80% VE it's closer to that brown mark in no-mans land on the left.

Remember this is also steady state air consumption. To get to that point it must climb up from the left.

12HT%20GT37%20Compressor.gif
 
Honestly Dougal, I think you need to re-read my intention from the start.

Further, you seem to have come down a fair amount in your estimation of theoretical spooling - looks close to 2000rpm to me when it starts to move along well! I have not stated anywhere that I thought this turbo would be ideal for a stock 12HT :deadhorse:

Obviously better to run in the middle of the map or on the choke flow side....
 
gbentink said:
Honestly Dougal, I think you need to re-read my intention from the start.

Further, you seem to have come down a fair amount in your estimation of theoretical spooling - looks close to 2000rpm to me when it starts to move along well! I have not stated anywhere that I thought this turbo would be ideal for a stock 12HT :deadhorse:

Obviously better to run in the middle of the map or on the choke flow side....
Click to expand...

That is a compressor map. It cannot predict when the turbo will spool up. It shows the stable operating range of the compressor.

Predicting spool up requires a turbine map and detailed knowledge of the exhaust flows, pulses and temperatures. Before you mentioned it was a VNT I showed the turbine map with 21 lb/min where the graph begins. That requires 4000rpm on a 4L engine.

I thought I knew your intentions (compound turbo 12HT), but that changed to a stroker 12HT, then to simple build and tuning of a 12HT. You mentioned possibly using a GT3782 and later said it was VNT. A turbo that big (VNT or not) is only useful for a dyno queen. Your reports of a whole heap of smoke to spool it reinforce that.
As the larger turbo in a compound setup it'd be fine.
 
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There has been alot of discussions and changes to what I have proposed, but I have been as descriptive as posisble in order to have any interested folks (interest is optional remember) be up to speed with what I am doing.

Easy to get confused though, it is now alot of text and might start a new thread perhaps.

I will make a brief summary as to current situation.

(1) I had two 12HT engines

(2) I sold the ported head engine (destined originally for twin turbo) in exchange for a rebuilder, so I still own two 12HT engines.

(3) One engine is in my HJ61 (Auto). It was in dire need of attention, so I rebuilt it over the last month or two. It is now running. One is to be pulled down and rebuilt in the performance mode. Alot of work will go into this one.

(4) The Running HJ61 is a perfect guinea pig for fabricating mounts for a water to air intercooler (or fitting up a GT3782VA and in particular improving the electronic actuation/control) and various other bolt on ancillaries that are intended to be bolted on to the spare "exchange engine" once it has been rebuild and installed in my 80 series Landcruiser (Auto). None are intended to stay on the HJ61 vehicle and any learnings captured are transferrable to the performance engine build. I was intending to keep the HJ61 (I have painted it and cleaned it up well), however I want/need the 3.5 tonne towing capacity of the 80 series.

(5) The running HJ61 is a perfect vehicle to test mods on the injector pump settings and see what is the maximum possible from an enhanced stock setup. This will give me an idea as to if there is much more to be gained and will form the basis for the direction the project follows there on after.

So I hope that explains clearly the current situation.

Also note that after I built the head up in the photos posted, I later discovered that I could very likely bore and stroke the 12HT a little bigger and indeed fit larger valves. Those fitted to the "performance head" were as big as possible given stock bore size. This, and the fact that I had already had the block bored, were the contributing factors to "starting again" with the exchange engine. Nothing at all has happened with the exchange engine. In fact, it is still in the donor car.

So there you have it.
 
This weekend I plan to do a g-tech of the HJ61. I will do in std settings (will be ~ 90whp) and at enhanced settings. I will also try to video both to get an even better feel for the changes.

Plans of mice and men though............
 
No worries Plumma, will see what I can doo. Still at fairly std stage at the moment, so if I keep doing videos over the same road/conditions everytime there is a significant change, might be interesting.

To Dougal: I called my Brother to ask what the VE pump was set to flow, he thought around 120cc. he also said that he did not have the right aneroid "piston" so was not sure how well it was working, he thinks it gave full fuel even without boost, hence smoke when loaded outside of boost range. I have been in a manual 80 series that had around 500nm. The Patrol had far more and I can only guess what it had. It seemed too much at the time. My spreadsheet tells me though around 600nm for the power it was making at those revs. He is going to have a look for the dyno graph. He may still have it. Previously he had a supercharger on the engine so the graph he has may only be from that, anyway, will have a look. I will try and get a picture of the setup. It was dynoed by Eddie Tassone in Perth who has a twin turbo V8 that makes 1700hp or some such thing. He was not the least bit interested in the diesel!!
 
gbentink said:
Check out Youtube YouTube - 12HT 1/4 Mile HJ61 18.04 seconds

This is std exhaust, extra fuel and 20psi (at a guess)

It is great to drive, and the mods have only just begun!
Click to expand...

Nice one.
So it starts moving about 7 seconds, so the 1/4 mile ends around 25 seconds at about 125 km/h?
Puts it about equal with a P38 rangerover with the 4.0 V8.
1999 Land Rover Range Rover 1/4 mile trap speeds 0-60 - DragTimes.com

Do you get much wheelspin or axle tramp off the mark? I see you're launching it around 2000rpm. The auto has a big advantage in sprints like this.
 
My G-Tech said 122hp @ wheels, but 1/4 mile times say over 160hp @ wheels. I felt confident that it is in the 120-130hp@ wheels range from driving other vehicles.

The HJ61 factory spec plate under bonnet says 2220kg, + 86kg driver + 45kg passenger + totally full fuel tank. I put 5300lbs in the G-Tech, calibrated the Gravity and got the 122hp.

No Axel Tramp at all or wheelspin, just moves along. I should upload the other video taken from the rear, with the same type of stall up.

The auto is great for the stall. Does ~ 12.5sec to 100km/h. My porkier HDJ81 did it in 11.8, but suprisingly the 12HT has a flatter torque curve.

My other car is a Lexus LX470 (So, petrol V8 Landcruiser 100 Series). My HJ61 feel like it has more torque down low (2000rpm) and probably similar performance. That would be an interesting comparison. I will egt a Mate to drive the Lexus.

I would like to take it over a weighbridge, there is one nearby at the lcoal rubbish dump, it is digital.

I would drive it faster, but my tyres are not round........ I think it might do 180...but that would be irresponsible and besides, it is kind of meaningless for the type of vehicle it is.

I havent uploaded the video to show exhaust because my number plate is showing, I wonder if that is OK?

I have an idea to control the aneroid using a ball/spring valve. This way I can limit max fuel. I can set aneroid itself to deliver maximum fuel and limit actual fueling by limiting pressure to the aneroid. Would be best if programmed vs rpm...... but better than nothing.

This, combined with a basic opacity meter would be useful for setting the max fueling. Of course, if you direct the exhaust sideways such that it can be viewed from the side view mirror, your eyes might serve the prupose just as well.

I really want to change the exhaust now, all I need it a bottle of gas for my TIG - I have everything else in 316 stainless!
 
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gbentink said:
My G-Tech said 122hp @ wheels, but 1/4 mile times say over 160hp @ wheels. I felt confident that it is in the 120-130hp@ wheels range from driving other vehicles.

The HJ61 factory spec plate under bonnet says 2220kg, + 86kg driver + 45kg passenger + totally full fuel tank. I put 5300lbs in the G-Tech, calibrated the Gravity and got the 122hp.

The auto is great for the stall. Does ~ 12.5sec to 100km/h. My porkier HDJ81 did it in 11.8, but suprisingly the 12HT has a flatter torque curve.

I would like to take it over a weighbridge, there is one nearby at the lcoal rubbish dump, it is digital.

I would drive it faster, but my tyres are not round........ I think it might do 180...but that would be irresponsible and besides, it is kind of meaningless for the type of vehicle it is.

I havent uploaded the cvideo to sho exhaust because my number plate is showing, I wonder if that is OK?

I have an idea to control the aneroid using a ball/spring valve. This way I can limit max fuel. I can set aneroid itself to deliver maximum fuel and limit actual fueling by limiting pressure to the aneroid. Would be best if programmed vs rpm...... but better than nothing.

This, combined with a basic opacity meter would be useful for setting the max fueling. Of course, if you direct the exhaust sideways such that it can be viewed from the rear view mirror, your eyes might serve the prupose just as well.

I really want to change the exhaust now, all I need it a bottle of gas for my TIG - I have everything else in 316 stainless!
Click to expand...

What governer does the inline pump have?
The one on my Isuzu (can't remember the codes) features a torque plate. This is actually a cam which rotates as pump speed increases. the shape of it determines how much fuel you can get relative to the set maximum rack travel.

Sounds like that would do everything you need. I suspect you've got a similar A type pump by zexel/diesel-kiki/bosch.

My truck also has a theoretical top speed of 180km/h and enough power to get there. But I have no desire to go there. My rev limiter is at 3600rpm and I'm happy leaving it there.
 
Unfortunately no cam plate..... I know the setup you mean and unfortunately, the 12HT runs a different setup altogether.

There are two screws that when adjusted set the basic fuel delivery vs rpm. Not a map as such, but you could set it to increase or decrease fuel linearly from 1500rpm to 3500rpm. The Torque plate adds another dimension!

Ours also has an aneroid to given extra fuel under boost. The mods done so far is only to increase the amount fo fuel under boost conditions.

It is not as good a setup as the Isuzu, the Isuzu also has better timing control I am lead to believe.... Anyway, it still does the job to a degree and while I thought about getting an Isuzu 6cyl pump, it really isnt worth the huge effort!

I am considering setting up my twin turbo system on this engine. I have a running 12HT....so why not. No commitment on my side, just toying with the idea.

I might consider using the boost between the two turbos to control the aneroid, This will serve to minimize torque down lower than 1400rpm (irrelevant area with Auto) and importantly minimize smoke.

The vane control for the VNT GT25 will be a misson and the most difficult aspect of the job. This is the main thing I am trying to escape.

The intercooler has arrived, just need to get my TIG up and running, and learn how to use it.....

Boost controllers will arive soon also.

On another forum someone said how slow 18sec 1/4 mile is. LOL, it is not a race car, I dont expect to ever get under 16. I want a good tow wagon and good on fuel plus a spirited drive.
 
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