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HO injectors vs Standard

3bals

3bals

Retired Firefighter
Messages
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Location
Minnesota
Here's the question:

I ordered HO injectors with my P400 from Peninsular. I had discussion with them and with Heath, as I was also replacing injectors on the K3500 this fall too. Well, Heath told me that I should not use the HO on my motorhome project, while Matt at Peninsular said I should.

Now I'm told the HO injectors are "supposed" to be en route here with the replacement transmission (after I sent pix of their absence), "supposedly" shipped on 12/19.

Anyhow, Now I'm not sure what to do. Order some standard Bosch injectors for the motorhome and sell the HOs or use them as planned?
 
Have read enough opposing commentary on HO, marine, and standard injectors to give even a conspiracy theorist a headache . . . Definitely not trying to insult the group of folks whom are truly smarter than myself in this area; just say-in.

I decided to follow Turbine Doc's voice which was Bosch marine's at 2,300 pop with the ATT; also I have the IP set at OE (-0.75 TDCO) and let the ECM control the advance. Motor seems happy with this combination but have yet to go WOT or tow as I am still under 1K miles on the new motor. So far, at ~75% power the motor is actually more quiet than ~50% power and am not noticing any smoke. It does belch at start-up.

Might try the RV forums to see if there are any active 6.5'ers and get a read on whether folks just went off-the-shelf when it was time to replace the injectors or actually built the motor to their own spec.

Toward the original question, am sure that somebody will chime-in with technical details to correct me, but my sense is that as long as the guts are Bosch, do what you are comfortable with and dial-down any smoke by re-tuning the ECM.
 
I have never heard anyone prove the magic 40 hp number gain, more like 10-15.

I have never heard anyone say the lost 1mpg, mostly 1/2.

So choose what is more important on the hiway to you- 15 ponies or 1/2 mpg. The important thing is that tune when it's all together to get the most out of both worlds.
 
More of the challenge is that most of the HO Injector are not Bosch.

They are Chinese made at least when you buy them out there like Ebay.

The real Bosch HO Injector is very pricy.
But this is a different case where Peninsular is actually a marine diesel supplier so they may have them anyway.

So, if Peninsular sent you an original Bosch then accept it graciously.
 
I just went through all this when I needed to replace the ones in my truck. I have a bigger injection pump so I went with new injectors to match it. I got brand new Stanadyne marine injectors and was around $550. Course I did the install of them.
 
So here's what I'm understanding. If I use the HO injectors I will gain some more HP it will cost me some MPG, but in my experience, more HP allows for more MPG.

Heath says not to use the HOs, but maybe that's true with a stock turbo set up and his tune. I told them what turbo I had, so that's why I'm questioning this. Pen says to use the HOs because they have built many of these engines and this is the best set up and they are supposed to be genuine Bosch injectors.

Speaking of Pen, I got a phone call from them yesterday afternoon to tell me that my new replacement transmission, HO injectors and the correct water pump should be arriving here yesterday or today. I haven't checked with my installer yet to see if it did. I thought it was odd that after all that has gone wrong, that they would make a personal call. It makes me wonder if they did read the other my thread that Hipster sent to them. I did ask them when the warranty would start too. They said it would start when the installation is complete and the vehicle is on the road. I and the installer are to email them when that time comes. We'll just have to see what the future brings.
 
When I needed injectors, Heath told me that for towing or heavy loads, you shouldn't use HO injectors; it'll only increase EGT's with minimal power gain. I put HO in because my Burb was just a people-mover. I had a stock turbo with Heath's Turbo Master (my vac pump died) with a 4" DE exhaust. I could get my EGT's up to 1250 going up a hill at WOT, but, other than that, I rarely went over 1100. I don't know if that's helpful or not, but it's my experience.
 
Bigger turbo, 4in exhaust turbo back, intercooler and water/meth injection. I'm not planning on any high EGTs. If anything the concern is having enough engine temp to run well.
 
Generically, EGT's will go up if the injectors / IP cannot spray enough fuel to keep up with the air and create a lean condition at WOT.

In the motor home's new configuration, the water injection may (not saying that it will) mask a lean condition and need for more fuel. Only thing that comes to mind in testing this out is to run with the WMI 'Off' and see if the EGT's skyrocket; if they do, the motor likely needs more fuel at WOT.

Am sensing that a good OBD-II configuration is a fuel system that is capable of delivering just a tad more fuel than the motor can burn (rich at WOT) and then dial-it back through tuning.


3bals said:
So here's what I'm understanding. If I use the HO injectors I will gain some more HP it will cost me some MPG, but in my experience, more HP allows for more MPG.
Click to expand...

Probably but, in reality, few people have enough self control to avoid the fun factor of smashing the pedal :D
 
JayTheCPA said:
Generically, EGT's will go up if the injectors / IP cannot spray enough fuel to keep up with the air and create a lean condition at WOT.

In the motor home's new configuration, the water injection may (not saying that it will) mask a lean condition and need for more fuel. Only thing that comes to mind in testing this out is to run with the WMI 'Off' and see if the EGT's skyrocket; if they do, the motor likely needs more fuel at WOT.

Am sensing that a good OBD-II configuration is a fuel system that is capable of delivering just a tad more fuel than the motor can burn (rich at WOT) and then dial-it back through tuning.




Probably but, in reality, few people have enough self control to avoid the fun factor of smashing the pedal :D
Click to expand...

Too much fuel and not enough air will also cause high egt's, and I guess too lean is the same as not enough air. :p

I am still learning but I'd love to know what HO injectors are or what makes them different?

DP tested marine vs turbo and found that unless the marine are matched with a marine pump, your wasting money and getting less performance as they don't flow as much fuel as turbo injectors.
 
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