1HZ "Turbo" injectors (2 Viewers)

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I am in the market soon for a set of injectors for my 77. I have read a few places to inform the injection shop if there is an aftermarket turbo fitted to the truck as they will change something.
I have heard its the breaking pressure of the injectors.
What is the purpose behind this?

This is from the HIFlo website:

Turbo injectors: Hiflo Turbo Injectors are special high pressure injectors designed for diesel engines fitted with aftermarket turbochargers.

Thoughts?
 
I too am in the same boat as you looking for higher flow injectors for my 3B. I have seen that often stock injectors are extruded honed to varying degrees to increase flow. I have never come across any toyota performance injector info as all I ever see is domestic stuff. I think, with my lack of knowledge on the subject, that this might work out alright as long as they dont leak as IDI spray pattern is not as a huge concern with the air/ fuel mixing mostly being done in the pre cup chamber. I have heard that after honing they injector might need higher crack pressure to help stop leaks. Very interested in all of this and will let you know if I find anything.
g
 
Thanks Gerg.
I have sent out a message to hiflo and I will report back with info.
 
not sure if what I'm gonna add it's really and add on .. but as you may know breaking pressure it's quite different from 1HZ to 1HD-T and even more with 1HD-FT so it would require more IP line pressure to work ... not sure if that's related to IDI vs DI or power production ..
 
not sure if what I'm gonna add it's really and add on .. but as you may know breaking pressure it's quite different from 1HZ to 1HD-T and even more with 1HD-FT so it would require more IP line pressure to work ... not sure if that's related to IDI vs DI or power production ..

Yes and I wonder how the fuel pump builds up the extra pressure and what are the long term consequences for the pump?
Many questions.
 
The increased cracking pressure is to improve atomisation of the larger fuel charge in a turbo setup. It's achieved by shimming the injector pin spring.

I doubt we are talking of much extra pressure, perhaps 100-200 psi. More than within the capabilities of the standard IP.

The IP elements are basically pumping into a 'dead head' situation until it over comes the spring force and pushes the injector needle back.

Better atomisation = more burn able fuel/air mixture = more power/less egts.

You can do this yourself, buy/hire a pop tester and a set of shims from Toyota.

All very simple
 
I think they are more than 200 psi ..

1HZ 2062-2205 PSI / 145-155kg-cm
1HD-T 1877-1963 132-138
1HD-FT 3356-3498 236-246
1HD-FTE 4864-5149 342-362
 
Just got this reply from eBay of all places. Sent messages to Hiflo, and United Fuel Injection. Nothing.

"for engines with aftermarket turbo, we just set the injector opening pressure slightly higher than standard.
we set them 5-10 kg/cm2 than the standard spec.
they still use the same genuine Denso nozzle as the normal spec injectors."

So that's 71psi - 142psi increase over standard.

image-1560213909.jpg
 
So then I wounder how we figure out if our stock injectors are a restriction for fuel delivery if our injection plungers are oversized? I calc that going from 7mm plungers now to 10.5 will double my fuel per stroke maxed out. I was planning on getting a spare set of injectors extruded honed and see what happens. After the pump gets done next fall or something. Id love it to be this spring but I have too much on my plate. It might be worth it to see what td42 guys do as they do play with their pumps, no pun intended, and get some very good power figures from those engines. I bet geremy knows about this stuff.
 
I've heard that guys with td42s get good results from bumping up the opening pressures (~100-200psi more) and advancing the timing a bit. Supposed to improve fuel economy a bit, although this may be peculiar to the td42. But I can definitely see how higher pressures would improve atomisation and economy/power. The patrol4x4.com forum has some good info on it.

There definitely seems to be a limit to how much you can increase it - to much and the injector spring starts to break
 
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So then I wounder how we figure out if our stock injectors are a restriction for fuel delivery if our injection plungers are oversized? I calc that going from 7mm plungers now to 10.5 will double my fuel per stroke maxed out. I was planning on getting a spare set of injectors extruded honed and see what happens. After the pump gets done next fall or something. Id love it to be this spring but I have too much on my plate. It might be worth it to see what td42 guys do as they do play with their pumps, no pun intended, and get some very good power figures from those engines. I bet geremy knows about this stuff.

Your planning on getting that done locally if I remember reading that somewhere correctly right?

My pump currently has 10mm elements, pre-99 1hzs have 10mm elements. Post 99 pumps were changed to 11mm and the later pumps had boost aneroids built in. 1hd-t and 1hd-fts have 12mm elements. 10mm pump is apparently good for 110-120 rwkw of power.

In 99 the injector spray pattern changed slightly while the angle the injectors changed also. This apparently was an increase in horsepower. I think the pistons changed ever so slightly as well. I wouldn't take my word 100% as this was awhile back. I forget what the 11mm and 12mm pumps do.

I'm wondering how much of a performance increase moving to a 11mm or even a 12mm pump.
My question is how would this be a performance upgrade for me if tuned to the same level, is it just essentially pumping more fuel through?

I've heard that guys with td42s get good results from bumping up the opening pressures (~100-200psi more) and advancing the timing a bit. Supposed to improve fuel economy a bit, although this may be peculiar to the td42. But I can definitely see how higher pressures would improve atomisation and economy/power. The patrol4x4.com forum has some good info on it.

There definitely seems to be a limit to how much you can increase it - to much and the injector spring starts to break

Here is some info on the td42 timing and injector info.

https://forum.ih8mud.com/diesel-tech-24-volts-systems/520211-downside-advancing-timing.html

I have the timing tool adapter for the 1h* diesels and a dial gauge but I haven't played around with timing the pump as of yet. I am curious on how much i would advance injection timing.

TD42 injection timing - 0.74mm +/- 0.02mm at TDC
1HZ injection timing - 1.06mm +/- 0.03mm at TDC
1HD-T injection timing - 1.32mm +/- 0.03mm at TDC

Now to get some data on how far I should advance my pump:hmm:
 
I'm guessing it would be a very small amount, just to compensate for the delay in injection due to setting the opening pressure higher.
Gerg are you going to be playing with the pressures on your 3B? If you have an in-line pump it would be a lot less prone to wear from increasing the pressures
 
I also did find out and forgot to post that I can fit any 1hz, 1hd-t or ft pump to my 1hz its the injectors though I have to fit the same injectors as they changed over the years. Pre cups themselves changed along with the head and injection nozzle themselves.

There is a fellow on Lcool that is running a 1hd-ft pump on his 1hz boosting 20lbs and has no shortage in fuel.
 
I wouldnt mind playing with injection pressures, but I must be honest in that I know very little about pumps.

After making many many calls I got told by all the big shops that they will not work on my pump at all. One did say they would, but specified that they would do no research and that I would have to bring them part numbers and they would be glad to rebuild and put new elements in.

The one old landcruiser injection fellow I had locally moved to Saskechewan and had a heart atack and heart surgery. Fortunately he didnt die. I have contacted him and he is willing to mess with the pump but not for many months for obvious reasons. I need to contact passenger performance and see what they do with their VW pumps as the do alot of high performance stuff locally here.

I did read an interesting opinion from old IDI cummins guys who actually dont want too good of a spray pattern as it could lead to greater burn in the precup and greater thermal loss subsiquently. This had never occured to me, but I could see that it could have merrit. If you had an amazing fine spray pattern and enough air, you would achieve in the pre cup area what you want in the cylinder. In my ignorance I understood that the pre cup chamber was only for air/fuel mixing and ignition, and not signifigant combustion. Thoughts?

Perhaps dougal or someone could speak to this as I only know enough to ask the question.
 
I really got to get off my backside and check and adjust my IP timing. I have the tool and dial gauge but I just

So after having a chat with Raj from Fred Holmes I found out this info.

Injectors:
They set them automatically 200-250psi above stock so when the springs wear out they are still hopefully above spec cracking pressure. He said they run fine at the higher psi.
$30 bucks a nozzle x 6 , 3-4 hours or labor at $98 dollars an hour, plus taxes. $640 bucks

Pump Info:
I discussed some of my options about pumps. I informed him I have a brand new boost comp waiting in a box for my pump.

Talked how the early 1hz pumps were 10mm plunger, is it worth it to upgrade to a 11mm or 12mm pump. He basically told me that it would not be completely necessary as he would be tuning the pump to my needs. He recommended that I just send him my pump and he could install and properly tune it to the boost setting that I am after. I still think I would run into maxing out the stock fuel pump.

7.5 hours of labor to fit the boost compensator and to test the pump properly. Said it was roughly $1100. This does not take into consideration if the seals are dried out and if the pump has too much play in certain areas. The rebuild just goes up from there depending on what needs to be replaced. He mentioned the parts that need to be replaced are included and shown why they were replaced. The spring in the diaphragm could be changed out to suit higher boost settings among other settings.

I brought up that I do come across pumps from later 1hz's and 1hd-ts and if it was worth it to me to buy a pump from Australia and use that as a core for a rebuild. With the increased fuel flowing through the pump in this case I would have to advance the timing slightly. To what number he does not exactly know as he has heard 1.2mm-1.3mm. I personally think this is still my best route and will be taken into consideration
 
Wow, all this stuf is rather pricey. For 600 bucks maybe ill just get a hydraulic jack, a guage , an old injector line and shim them myself.

I can get complete injectors redone with genuine nozzles for cheaper shipped from overseas.

I'm going to fit my boost comp myself. I took it apart tonight to play with it. I know she's going to be a finicky little thing. I plan on leaving it stock at this point to keep things simple.
 
A boost compensator would be nice, but I do like to smoke out my buddies on the hills sometimes as a joke. I have both types of pumps and I think ill just go without for the fun.
 
I am after max fuel economy if possible.
She's not smoking but if I could be fueling less for when I am not in boost that would in theory save fuel. I get I have a turbo and all but i still have faith I can have some sort of fuel savings instead of constant overfueling
 

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