Injection Pump Efficiency

[Turbine Doc]

OOPS but you started it opened the door to OT & hijack with GL 4 question then it got into lift pumps/OPS & boost refefences

Yeah, I guess I need to look into that. The obd1 guys have it easy with scanners, obdII software is not so cheap. Changing the topic a bit, is anyone running the GL-E upgrade? Sounds like a good option. What are the thoughts out there?

But yea we hijacked it some, sorry :mad2:

 

[mfgguru]

No biggy. It's interesting to hear your results non the less. My biggest question has, I think, been answered, and that was can an aged IP affect mileage directly. I used to get 20mpg plus, now its 15-18. I guess there are many factors. Even at the MPG gains of the GLE, I will still buy the GL4. More bang for the buck, literally. Just need to get that guage and then I'm all set. Got some stroker friends that need tuning in!

 

[Turbine Doc]

No biggy. It's interesting to hear your results non the less. My biggest question has, I think, been answered, and that was can an aged IP affect mileage directly.

Yes it & injectors only good for X # of squirts.

 

[mfgguru]

So what is the projected mileage before they start to degrade? I have new injectors, but the pump has a 156 000 miles on it, original in the truck. Do you think it is time to put in a rebuilt? I have 2 cores that I bought cheap, the PMD's lasted me about a week each, so I guess they were shot, but the pumps may be low milers. Any way I can check to see how many miles they had before they were swapped, assuming they were swapped on warranty?

 

[Turbine Doc]

Depends on care & feeding, Heath & Diesel Pro over on other site say 100K is time for injectors, Ip 150K or until you start seeing issues like you describe, yet there are guys who have 250K on em, I'd say from your description time to give one of our vendors a shout and start pricing one.

 

[mfgguru]

Thanks Doc. Have a good weekend ALL!!

 

[Goldsburg]

With my ATT yes, not so with my GM-8 my drive pressure was 2x and almost 3x when high boosting, but I had the WG fully gagged shut so it could never open and EGT was 900-950 pre-turbo there...

Sorry for the off topic, but wanted to finish this thought.

With the W/G wired shut, you are driving much more exhaust power through a turbine housing that was not designed for it. So yes with decreasing efficiency of the turbine at those power input levels combined with the horrible inefficiency of the compressor side at high boost levels (16+ psi?), I could easily see how you got 2X and maybe 3X boost pressure in the TDP.

When the turbine side is properly sized to output, like my current GM-4 to my stock fueling and your ATT with your Heath fueling, you will see the "correct" or "usual" response of TDP to boost.

Regards,