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Good news Cp4 to Cp3

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The question is - for how long can they do it?
Sure one can test out the design limits, but i wont spend a cent to do so.

I strongly don't believe that Cummins changed the pumps for cost reasons, that is nonsens on a 90K $ Truck to have maybe a difference of 50$.
$50 over 100,000 trucks is $5,000,000 that’s a hell of a lot of money. So yea I can see them doing an hopefully the cost cut lasts until just outside of warranty. They make these cost compromises all the time at our expense. Some times they get lucky and they are heroes.... Sometimes not so much.... Ether way we end up paying.
 
All I heard was the CP3 couldn't deliver the pressures needed and that is why they HAD TO go to the 4.

Flow at higher pressures, the CP-3 was close to tapped out without modifications. CP-4 is lighter, less moving parts, cheaper. Has to better, right?

Change piston size, change lift on the lobes, pull one piston out, aluminum body, wonder why stresses increase and the parts fail. Bosch develops around EURO fuel, not the same thing as we have here. Production tolerances and metallurgy need to be much tighter, that didn't happen. Pretty much a repeat of the original CP-3 and CR injectors. It should be the same design as CP-3 where rail fuel is prioritized, when it hits the limit lube and cooling fuel is scavenged for rail and there is where the issues start. On a detuned commercial fleet vehicle it is probably a lot better, not so much with the big numbers they are claiming for the pickups.
 
Flow at higher pressures, the CP-3 was close to tapped out without modifications. CP-4 is lighter, less moving parts, cheaper. Has to better, right?

Change piston size, change lift on the lobes, pull one piston out, aluminum body, wonder why stresses increase and the parts fail. Bosch develops around EURO fuel, not the same thing as we have here. Production tolerances and metallurgy need to be much tighter, that didn't happen. Pretty much a repeat of the original CP-3 and CR injectors. It should be the same design as CP-3 where rail fuel is prioritized, when it hits the limit lube and cooling fuel is scavenged for rail and there is where the issues start. On a detuned commercial fleet vehicle it is probably a lot better, not so much with the big numbers they are claiming for the pickups.

Did Bosch include the return fuel mod that the aftermarket came up with? NO as far as I know. Tone deaf? Cummins allowed Bocsh to put their engine reputation on the line! Ford, VW, GM and now RAM take the hit. Elect HP4 in 2021!
 
Three pages of hype, zero information to back it up...people waxing on and on about how great the CP3 is.

I don't believe for one minute RAM is making this change, nor do I believe they will be "retrofitting" an older pump to a newer engine that was never designed for it. Show me the proof and I'll believe it...
 
Three pages of hype, zero information to back it up...people waxing on and on about how great the CP3 is.

I don't believe for one minute RAM is making this change, nor do I believe they will be "retrofitting" an older pump to a newer engine that was never designed for it. Show me the proof and I'll believe it...

You might say the OP knows a thing or two. Just saying.
 
I'm happy to believe it with proof. The fuel system is the heart of a diesel engine, and I'm skeptical Cummins can meet both emissions and sound targets with the CP3...otherwise, there'd be no reason for a change. Cummins is not an ignorant company....they are well aware of the failures in the past with the CP4 on Ford and GM engines. If targets could be met, it sure would make sense to keep the CP3, especially if it would lower warranty payout.
 
Three pages of hype, zero information to back it up...people waxing on and on about how great the CP3 is.

I don't believe for one minute RAM is making this change, nor do I believe they will be "retrofitting" an older pump to a newer engine that was never designed for it. Show me the proof and I'll believe it...

While I also would like an explanation of source, I DO know that Bob4x4 would NOT simply be spreading rumors and also his position within the dealership network would make him aware of Rams plans.
 
If Industrial Injection can install a CP3 on a Cummins with the timing case and tuning designed for the CP4, I think Cummins would have no problem doing so... This is also not a new engine platform, rather it’s just an upgraded ISB.

I really do hope this information comes to fruition. It would negate the need for me to make my own “disaster prevention“ block for the CP4...
 
Does Industrial Injection have to meet EPA certification, which has become extremely strict as of late? If the CP3 can do it, why did Cummins change? What are the drawbacks of the CP3 vs CP4? Does not make sense...
 
If Industrial Injection can install a CP3 on a Cummins with the timing case and tuning designed for the CP4, I think Cummins would have no problem doing so... This is also not a new engine platform, rather it’s just an upgraded ISB.

I really do hope this information comes to fruition. It would negate the need for me to make my own “disaster prevention“ block for the CP4...
I just looked at their information and it says it requires no tuning. It also does not say it has a CARB number, so I would doubt it is actually legal and emissions compliant.
 
Does Industrial Injection have to meet EPA certification, which has become extremely strict as of late? If the CP3 can do it, why did Cummins change? What are the drawbacks of the CP3 vs CP4? Does not make sense...

If tuning isn’t changed, and the CP3 is modded to match the performance of a CP4, emissions output doesn’t change.

There are a few reasons why CP4 is used. It’s newer, cheaper, lighter, and able to produce higher pressures. Unfortunately, the drawback is its reliability.
 
Side Note: Look at all of the issues CAT has had with the HEUI pumps on their engines. I do know for a fact Cat will throw mega bucks at an inferior design, if a VP is behind this design. And the poor customer in the long run ends up paying for the repair dollars when a design fails do to being an inferior design.

A lot of these design issues can be traced back to the EPA and the emission compliant requirements. The Design team is trying to meet these emission requirements in a cost effective way and sometimes this leads to an inferior design being used to meet them. The only reason that I see the need for higher injection pressures is to allow the combustion process in the engine to meet the latest diesel emission requirements at the tail pipe. The higher fuel pressure may allow for a more thorough burn of the fuel since it is atomized in a finer spray at this higher pressure!

Just my thoughts on this.
 
I just looked at their information and it says it requires no tuning. It also does not say it has a CARB number, so I would doubt it is actually legal and emissions compliant.

They say it is emissions compliant..... I doubt it would be worth the $$$ to make such a statement only to turn around and get sued. I also don't see the usual disclaimer stating "For off road use only". I'm not defending Industrial Injection but all they are providing is the latter proven HPFP from the previous year trucks that's been slightly modified to provide the same pressures/flow. If the pump increases the emissions above factory specs, it’s considered illegal for use on public roads in states that have adopted the CARB emissions standard.

I just had quick phone with Industrial Injection.. They said it is fully compliant with CARB's requirements and changes nothing with the emissions generated or emissions system operation, They've also submitted everything needed to get an EO number and now it's just the waiting game with them. He also said that they get about 5 calls a day regarding the kit and that they have heard of more than a few Cummins CP4 failures.
 
Another thing to look at is the CP4 that is used across the board on earlier model vehicles, the same design pump as what is used in with the Cummins engine? I believe I read somewhere that the Cummins fuel pump was a CP4.2 model. This tells me that the pump has gone under some deign iterations (changes) so, maybe Bosch has addressed the early design failures of the earlier model CP4 pump.

I know that when I was working with REXROTH to address some pump failures with their load sensing pumps. Several changes were made to address these failures but the model name or series nomenclature was never changed. But the pumps built in the later years were light years ahead in reliability over the earlier model pump!

Just saying!
 
Another thing to look at is the CP4 that is used across the board on earlier model vehicles, the same design pump as what is used in with the Cummins engine? I believe I read somewhere that the Cummins fuel pump was a CP4.2 model. This tells me that the pump has gone under some deign iterations (changes) so, maybe Bosch has addressed the early design failures of the earlier model CP4 pump.

The CP4 aka CP4.1 is a single piston pump found on small 4 and 6 cylinder diesel's.... The CP4.2 pump is a 2 piston pump hence the .2 model designation. My wife's Audi Q5 V6 TDI has a CP4.1 pump.

CP4.1
CP4.1.jpg


CP4.2
Bosch CP4.jpg
 
Another thing to look at is the CP4 that is used across the board on earlier model vehicles, the same design pump as what is used in with the Cummins engine? I believe I read somewhere that the Cummins fuel pump was a CP4.2 model. This tells me that the pump has gone under some deign iterations (changes) so, maybe Bosch has addressed the early design failures of the earlier model CP4 pump.

I know that when I was working with REXROTH to address some pump failures with their load sensing pumps. Several changes were made to address these failures but the model name or series nomenclature was never changed. But the pumps built in the later years were light years ahead in reliability over the earlier model pump!

Just saying!

CP4 is a general name. The .1 or .2 indicates the number of pistons the pump has. So the CP4.2 has two pistons.
EDIT: R. Taylor beat me to it

As for the pump, it’s is just a bad design. Talked with Bosch certified techs that work on VW, Audi, etc. and they know that the pump is just poorly designed. Needs to be scrapped.
 
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