PI or HPFP upgrade?

[-Eidos]

Originally Posted by ASTATENATE

I’m confused. Everywhere states EU5 is good for 800 whp on E85…Attachment 3405930

Furthermore, Stage 3 ones you speak of. Is only rated at 730whp. And that’s from their direct site.

Attachment 3405931

It's in Dorch's best interest to not direct people to Nostrum. They're competitors.

And on the Nostrum site, scroll down to the EU5 flow comparison.

[ASTATENATE]

EU5 is OEM. And capable of 800whp.

Nostrum own website Stage 3 injector is 730whp capable it says , no competition.

I don’t think the bottle neck is my EU5’s. I just believe PI will net me my goals, safely and have headroom for more (if needed) where as HPFP is good for my goals. But no much , if any , more.

[-Eidos]

Originally Posted by ASTATENATE

EU5 is OEM. And capable of 800whp.

Nostrum own website Stage 3 injector is 730whp capable it says , no competition.

I don’t think the bottle neck is my EU5’s. I just believe PI will net me my goals, safely and have headroom for more (if needed) where as HPFP is good for my goals. But no much , if any , more.

EU5 does not have the OEM spray pattern for our EU6 cars. Nostrum maintains the EU6 spray pattern and flows more. You're mistaken.

[ASTATENATE]

Originally Posted by -Eidos

EU5 does not have the OEM spray pattern for our EU6 cars. Nostrum maintains the EU6 spray pattern and flows more. You're mistaken.

Everywhere I read EU5 spray pattern is better. Regardless of flow rate of the injector. The topic at hand is PI vs HPFP.

I believe the only reason people started installing HPFP over PI once released it ease of install, less parts to go bad. Which is what looks appealing to me as well.
But I’m looking for pros/cons of each from people who drive or race these setups daily. No offense, but every tuner I have spoke to said EU5 is plenty for 800 whp on E85. Which I will not be pushing these that high. The true bottle neck of the fuel system is LPFP (once you have upgraded HPFP or PI) which I’ve taken care of by going Stage 3 brushless LPFP. The next item to tackle is HPFP which is rated to flow 38% more fuel over OEM HPFP. Per Dorch website. Which is okay, as E85 requires 30-40% more fuel. But if I’m maxed out on E50 currently on stock HPFP. That means upgrading to 38% more and going back to full e85. I’ll be back to pushing the HPFP to its limit. With little to no headroom. Where as PI would give me supplemental headroom and room to grow if I ever wanted to build motor and upgrade injectors in the future. The only con to PI is more technical install (splicing into DME) and more parts that could possibly fail.

[-Eidos]

Originally Posted by ASTATENATE

Everywhere I read EU5 spray pattern is better. Regardless of flow rate of the injector. The topic at hand is PI vs HPFP.

I believe the only reason people started installing HPFP over PI once released it ease of install, less parts to go bad. Which is what looks appealing to me as well.
But I’m looking for pros/cons of each from people who drive or race these setups daily. No offense, but every tuner I have spoke to said EU5 is plenty for 800 whp on E85. Which I will not be pushing these that high. The true bottle neck of the fuel system is LPFP (once you have upgraded HPFP or PI) which I’ve taken care of by going Stage 3 brushless LPFP. The next item to tackle is HPFP which is rated to flow 38% more fuel over OEM HPFP. Per Dorch website. Which is okay, as E85 requires 30-40% more fuel. But if I’m maxed out on E50 currently on stock HPFP. That means upgrading to 38% more and going back to full e85. I’ll be back to pushing the HPFP to its limit. With little to no headroom. Where as PI would give me supplemental headroom and room to grow if I ever wanted to build motor and upgrade injectors in the future. The only con to PI is more technical install (splicing into DME) and more parts that could possibly fail.

Better? The spray pattern is different than what the EU6 cars are designed for. And again, the whp rating for the injectors depends on AFR targets and tuning stategy. If you believe the EU5 800whp rating, and Nostrum rates their Stage 3s to flow 31% more than the EU5s, then do the math.

This is my road course car maxing out the EU5s targeting a low 12 AFR on E85. We could have pushed more if we leaned it out, but that wasn't the goal. After upgrading to Nostrum Stage 2s, we've had plenty more headroom and I can't imagine what the Stage 3s would entail.

My entire point is, after upgrading your HPFP, your DI will still have more headroom if you upgrade your injectors further. There won't be a need to blend down or lean things out, which is what people tend to do on EU5s.

[wheela]

As far as cons to PI, consider controller reliability. I'm not saying any of the aftermarket PI controllers have reliability issues, but I definately feel more confident with an oem quality DME manufactured by Bosch vs. something designed and built by an aftermarket tuning company.

Manufacturers are switching to DI because it's a better technology. Tuners tend to be more comfortable with PI because its been around longer. Some of the b58's are now incorporating PI with DI, but I believe that is for the intake valve cleaning PI provides. But really, whatever system can provide enough fuel for your goals is probably fine.

Fuel injection is very complex. It's good to get peoples' opinions on forums, but to really feel confident in your decision, your going to need to go down the rabbit hole a bit to decide for your self. Check out actual engineering forums, and published research articles on DI. It will take a while to weed through all the details, but it will be worth your time in the end as you'll be making an educated decision.

[wheela]

Also look into minimum timing for best torque. Timing values aren't apples to apples either. It's incredibly complex when you get into the technical details. It's been said here that DI needs leaner afr's than PI. But both are already richer than stoich. It may be semantics, but a more accurate way too look at it may be that PI needs richer AFR targets than DI.

[ASTATENATE]

Originally Posted by -Eidos

continued… There won't be a need to blend down or lean things out, which is what people tend to do on EU5s.

I agree with your logic. I just don’t want to go backwards and do injectors again. I appreciate the advice. More so just looking for “hey install HPFP screw what the tuner thinks” or “PI is a better option and able to hit richer, safer AFR targets, go that route.” So far everyone is for HPFP. And I get it. Ease of install, less parts. It’s got its pros for sure. But with my current setup (not wanting to change anything, only add) I’ve got EU5, I’ve got upgraded LPFP. So what’s next on the list is either Dorch HPFP or PI kit with Reflex+

Originally Posted by wheela

continued… It will take a while to weed through all the details, but it will be worth your time in the end as you'll be making an educated decision.

I appreciate all your information. I’m just new to a DI setup. And it’s all confusing, I started to go down the rabbit hole and that is why I started this post specifically to weed out. I want to go with PI (for the simple fact my tuner who is clearly a tuner for a reason recommends it) and I feel like trusting your tuner is best. But it’s hard when so many people are telling me to go HPFP route. And I trust Motiv (even being an aftermarket software/hardware, I hear nothing but great things. And the safety nets and aux connects that are available on the Reflex+ are a pretty nice option) I’m not going cheap on PI controller like AIC or others for this very reason. I’m more so worried about injector failure or something along those lines. I am going Bosch 750cc nothing cheap. If I go that route.

& I won’t even begin to start on timing

[JustAnothaM4]

Do as you wish man...if you choose to go PI because your tuner says so then by all means...

Most people already told you that you don't need PI for your power goal. Upgraded DI setup is safe, reliable, and proven!

[ASTATENATE]

Originally Posted by JustAnothaM4

Do as you wish man...if you choose to go PI because your tuner says so then by all means...

Most people already told you that you don't need PI for your power goal. Upgraded DI setup is safe, reliable, and proven!

Waiting for tuner to respond with explanation after all of you all advice. I’ll be purchasing something this week. Ready for 700+

[RAT3DM]

Originally Posted by TopJimmy

Only do PI if you’re going all out, otherwise beef up the DI system. Less cost, less boxes, less risk.

Biggest DI, HPFPs and the LPFP. I’m thinking the Nostrum Stage 3 kit with injectors and HPFPs.

I went a similar route and should have some results for the group. All DI Nostrom Stage 3 injectors, Dorch liftkit HPFP and Raceworks STG 3 brushless LPFP.

[astris]

Originally Posted by RAT3DM

I went a similar route and should have some results for the group. All DI Nostrom Stage 3 injectors, Dorch liftkit HPFP and Raceworks STG 3 brushless LPFP.

I’ve been running the eu5/dorch/pr stage 3 brushless setup for… wow, almost 2 years now! Been debating playing about with the Nostrum Stage 3 injectors. I’m already pushing the rod limits on E85 though. Either way, interested in your results. 👍

[RAT3DM]

Originally Posted by astris

I’ve been running the eu5/dorch/pr stage 3 brushless setup for… wow, almost 2 years now! Been debating playing about with the Nostrum Stage 3 injectors. I’m already pushing the rod limits on E85 though. Either way, interested in your results. 👍

I ran the Eu5's previously, but wanted the extra head room with my new built motor. I'll keep you posted.

[ASTATENATE]

Originally Posted by RAT3DM

I ran the Eu5's previously, but wanted the extra head room with my new built motor. I'll keep you posted.

Would you say (stock engine) EU5 is sufficient?
I’ve never heard issues unless you’re 800+ whp on EU5’s until this post.

[astris]

Originally Posted by ASTATENATE

Would you say (stock engine) EU5 is sufficient?
I’ve never heard issues unless you’re 800+ whp on EU5’s until this post.

Yes. I’m at 706whp/660wtq. Been running this setup for 2 years now as mentioned. Close to the EU5 limits, but still have some headroom.

[RAT3DM]

Originally Posted by ASTATENATE

Would you say (stock engine) EU5 is sufficient?
I’ve never heard issues unless you’re 800+ whp on EU5’s until this post.

IMO you need to ask your tuner what the duty cycle is on the injector at 800WHP, as Astris indicated I see alot of people in the 700-740whp on EU5's with a little headroom.

The extra injector is there for safety and availability to push further than the Eu5; however the cost difference is 3 times as much. I understand why most people wouldn't want to do it as the cost per HP goes up. Gotta pay to play!

[ASTATENATE]

Y’all make me want PI more and more with each comment LOL! Bosch 750cc injectors on top of EU5 = plenty of head room, no problems with EU5 being at a high duty cycle. Keep things safe with room for error. Really only con to me at this point is hardware failure. Which can happen with DI, PI, on stock levels.

[astris]

Originally Posted by RAT3DM

IMO you need to ask your tuner what the duty cycle is on the injector at 800WHP, as Astris indicated I see alot of people in the 700-740whp on EU5's with a little headroom.

The extra injector is there for safety and availability to push further than the Eu5; however the cost difference is 3 times as much. I understand why most people wouldn't want to do it as the cost per HP goes up. Gotta pay to play!

Originally Posted by ASTATENATE

Y’all make me want PI more and more with each comment LOL! Bosch 750cc injectors on top of EU5 = plenty of head room, no problems with EU5 being at a high duty cycle. Keep things safe with room for error. Really only con to me at this point is hardware failure. Which can happen with DI, PI, on stock levels.

That’s a massive downside IMO. How many additional parts does PI add? That’s a lot of failure points, all for parts never meant to be part of the fuel system.

Oh and I don’t know if anyone explicitly stated it, but 700whp ish is on E85. I’m sure on race gas and a big single EU5s are capable of more.

[ASTATENATE]

I believe you’re only adding the PI controller which is DME operated. It’s spliced into DME. You mainly just have to worry about the 6 additional injectors would be an added failure point.

[-Eidos]

Originally Posted by ASTATENATE

I believe you’re only adding the PI controller which is DME operated. It’s spliced into DME. You mainly just have to worry about the 6 additional injectors would be an added failure point.

It's DME operated via the Motiv Reflex, but the level of control over the PI injectors is surface level compared to how the DME controls the DI injectors.

[imperfectluck]

Just wanted to chime in once more and nudge to get the fuel filter, can’t stress enough when Ian from Bend Calibration told me to look at the pics of when a cylinder leans out and the DME didn’t have time to react.

I’m running just about the same setup as astris as I saw the results and was impressed to follow suit. It was said earlier in this thread just wanted to once more stress this point so that you don’t end up making a thread about it as we’ve seen every now and then especially if you plan to run high E levels.

[ASTATENATE]

I’m not against a fuel filter. No matter which route I go. I’ve looked into them.