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Discussion Starter #1
With FBO + tune what is the max E% you can run on the stock fuel system, what about with just LPFP?

after doing every bolt on i want to run E30-40 with flex fuel. But would prefer to avoid HPFP if possible. AMS said need HPFP and LPFP but I believe they where talking for E85.
 

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Discussion Starter #2 (Edited)
After doing some more research, and obviuosly it varies based on boost. but generally stock system is good for E25 and E30 with LPFP.
E30 also looks like the max you can run without actually tuning and adjusting fueling to accommodate the difference in energy with ethanol %
I have a LPFP and JB4 coming soon so will be testing this out on E30.

I assume since pretty much all gas by default has E10 in it the stock “tune” is set to account for E10 so E30 is only 20% more ethanol. With ethanol having roughly 1/3 the energy adding 20% higher ethanol mix should inherently lean out the fuel mixture 7%. With the stock tune being so rich especially for direct injection (I’m assuming to accommodate 91 octane) leaning out 7% with a higher octane equivalent fuel should be perfectly safe and generate more power by being a leaner AFR (assuming this is why stock tune and stock boost cars pickup roughly 20whp on E30 mix with no other adjustments)
 

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After doing some more research, and obviuosly it varies based on boost. but generally stock system is good for E25 and E30 with LPFP.
E30 also looks like the max you can run without actually tuning and adjusting fueling to accommodate the difference in energy with ethanol %
I have a LPFP and JB4 coming soon so will be testing this out on E30.

I assume since pretty much all gas by default has E10 in it the stock “tune” is set to account for E10 so E30 is only 20% more ethanol. With ethanol having roughly 1/3 the energy adding 20% higher ethanol mix should inherently lean out the fuel mixture 7%. With the stock tune being so rich especially for direct injection (I’m assuming to accommodate 91 octane) leaning out 7% with a higher octane equivalent fuel should be perfectly safe and generate more power by being a leaner AFR (assuming this is why stock tune and stock boost cars pickup roughly 20whp on E30 mix with no other adjustments)
I don't what HP to expect with E30 on stock turbo. I know people who do run E30 with no issues. I just don't see the point of running a flex fuel set up and having to pay for 2 tunes if you're not going E85. You are on JB4 so you'll definitely see gains.
 

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Discussion Starter #4
I don't what HP to expect with E30 on stock turbo. I know people who do run E30 with no issues. I just don't see the point of running a flex fuel set up and having to pay for 2 tunes if you're not going E85. You are on JB4 so you'll definitely see gains.
going from E10/93 to E30/93 should still pickup a noticeable difference in HP. but mostly for people limited to E10/91 going to E30/91 will be a decent jump not only in power but in safety margin when trying to turn up the boost.
If running E30 or below Flex Fuel is probably not worth it, but if you want to run much higher E% and get the FF kit, HPFP/LPFP a tuners chare between 150-300$ for a added flex fuel tune and then you have the ability to run any mix of ethanol without having to worry.
 

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I'd avoid using Eth blends all together a large number of people have reported multiple and continued fuel injector failures
while running Eth blends above E20 on the stock fuel system and to address the issue is fairly expensive.

IMO you are better off going with Meth setup or finding some higher octane fuel from one of the local gas stations and getting a tune for that.
 

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Discussion Starter #6
I'd avoid using Eth blends all together a large number of people have reported multiple and continued fuel injector failures
while running Eth blends above E20 on the stock fuel system and to address the issue is fairly expensive.

IMO you are better off going with Meth setup or finding some higher octane fuel from one of the local gas stations and getting a tune for that.
It looks like the majority of those people had the failures when installing HPFP without an inline fuel filter. and probably just as many people running on pump gas had the same failure at the same rate as those running E20-E30 without the HPFP.
 

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I'd avoid using Eth blends all together a large number of people have reported multiple and continued fuel injector failures
while running Eth blends above E20 on the stock fuel system and to address the issue is fairly expensive.

IMO you are better off going with Meth setup or finding some higher octane fuel from one of the local gas stations and getting a tune for that.
I am staying away from ethanol blends. This is the reason I am going to a meth set up. No need to add flex fuel or worry about fuel system issues. I hope with upgraded turbos and meth, 550 whp is achievable. This seems to be the cheaper alternative also to flex fuel set ups.
 

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It looks like the majority of those people had the failures when installing HPFP without an inline fuel filter. and probably just as many people running on pump gas had the same failure at the same rate as those running E20-E30 without the HPFP.
I've seen maybe 1 or 2 people report a fuel injector failure running on regular pump gas and every other instance of maybe 2-3 dozen people were running Eth blends be it with a HPFP or on the stock fuel system. Considering the number of fuel system modifications now available for the VR30 platform I feel like the stock fuel system was never designed to run higher Eth blends rather than a single component bottle-necking the system, heck AMS just released new OE replacement fuel rails for the VR30 these past few weeks.

Was not running an inline filter the issue? Maybe but I'm not going to be recommending Eth blends to people any time soon for these engines.
 

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I believe a pre-rail filter isn't a guaranteed fix either given the AMS analysis. They alluded to the fact that the inside of the rails are chipping off and getting stuck in the injector. A pre-rail filter won't fix this.
 

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Discussion Starter #11
I believe a pre-rail filter isn't a guaranteed fix either given the AMS analysis. They alluded to the fact that the inside of the rails are chipping off and getting stuck in the injector. A pre-rail filter won't fix this.
I saw that article but it didn’t seem 100% conclusive. I also saw a lot of people thinking/assuming it was contaminants introduced from the install. And peoples findings indicating a large portion of failures happened in the 1st week after install of HPFP but if they made it past the 1st week or two tha failure rate drastically reduced. Which would indicate contaminants from install.
 

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I saw that article but it didn’t seem 100% conclusive. I also saw a lot of people thinking/assuming it was contaminants introduced from the install. And peoples findings indicating a large portion of failures happened in the 1st week after install of HPFP but if they made it past the 1st week or two tha failure rate drastically reduced. Which would indicate contaminants from install.
There's no way that many people "contaminated" their fuel system by simply removing a pump to replace it. I've taken fuel rails off other platforms dozens of times making more power than 99% of the people on this platform. I believe that most of the people that had issues were a combination of running a higher fuel pressure combined with the corrosive properties of Ethanol. Basically everyone who swapped their fuel pump did so because they were running higher Ethanol content, which is more corrosive.
 

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Discussion Starter #13
I've seen maybe 1 or 2 people report a fuel injector failure running on regular pump gas and every other instance of maybe 2-3 dozen people were running Eth blends be it with a HPFP or on the stock fuel system. Considering the number of fuel system modifications now available for the VR30 platform I feel like the stock fuel system was never designed to run higher Eth blends rather than a single component bottle-necking the system, heck AMS just released new OE replacement fuel rails for the VR30 these past few weeks.

Was not running an inline filter the issue? Maybe but I'm not going to be recommending Eth blends to people any time soon for these engines.
after FBO+tune people are making roughly 30-50% more power vs stock(depending on rs or ss)

most stock fuel systems are designed to only handle about 40-50% more power. So people are near maxing the fuel system add in E85s increased power and 30% greater demand and your system is going to be at 100% all the time that will inherently wear out the fuel system much faster leading to failures. But i don’t believe the failures are specifically do to ethanol if you can keep injectors below 85% duty cycle. Which with FBO and turning boost to 19 is impossible. Now FBO and 15psi you may have the head room for some ethanol without maxing the injectors/fuel system
 

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Discussion Starter #15
Not sure what you're getting at. Most tuned cars run 19 psi or more. 15 psi is basically stock RS levels....
FBO + 19 psi on regular pump gas is pretty much maxing the stock fuel system, maybe a tiny bit of headroom for safety/reliability. But with the added fuel demand of ethanol on top of all that, it is going to be running the fuel system and injectors at pretty much 100% duty cycle, eating up all that safety/reliability head room. Running maxed injectors leads to increased wear, tear, and failure of fuel components especially injectors. (This isn’t unique to this car, or ethanol) typically you only want 80-85% max duty cycle. At 100% duty cycle not only do you leave no room for added fuel If you need it, but you are constantly providing 12v without any “cycling” breaks and it will overheat the injectors quickly leading to failure.

my point of 15psi is maybe lowering boost 4psi may free up the Injector duty cycle enough to be only at 85% with E30. (Would need to test to confirm) And have the ability to advance timing from the higher octane fuel to regain some of the power lost and also have all the other benefits of ethanol like cooler cylinder temps, and greater knock resistance for greater safety and reliability while making close to max hp.

So my theory is that the failures that where not from contamination are from maxing injectors too long. Not from any inherent corrosive properties of ethanol but the increased fuel demand.

i would be curious to see data on people running E30 completely stock and stock tune/boost who had injector failures vs stock w/ pump gas injector failures. Or is the vast majority of injector failures from either A. People who replaced HPFP and introduced contaminants or B. People with FBO + high boost tunes maxing injectors and adding E30.
 

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You are assuming that the modded cars with fuel pumps are hitting 100% IDC, which is the entire point of putting the fuel pump in. This platform is closed loop at WOT with wideband O2 fuel correction. So adding a fuel pump would LESSEN the chance of overworking an injector because each squirt would add more fuel with an upgraded fuel pump. If your theory were correct the cars with stock fuel pumps and E would break and the cars with aftermarket fuel pumps and E would live.
 

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after FBO+tune people are making roughly 30-50% more power vs stock(depending on rs or ss)

most stock fuel systems are designed to only handle about 40-50% more power. So people are near maxing the fuel system add in E85s increased power and 30% greater demand and your system is going to be at 100% all the time that will inherently wear out the fuel system much faster leading to failures. But i don’t believe the failures are specifically do to ethanol if you can keep injectors below 85% duty cycle. Which with FBO and turning boost to 19 is impossible. Now FBO and 15psi you may have the head room for some ethanol without maxing the injectors/fuel system
Except that's not how boost curves are calibrated, the car is only running at peak boost at very specific RPM ranges typically around 5500-5800RPM,
after-which it quickly drops off as the turbos are far outside their efficiency tables and only creating massive amounts of heat.

So even if the injectors are being pushed harder they aren't operating at 100% the entire time, so while failiures should
appaer they wouldn't be in the number we've witnessed. In fact AMS weighed in on this particular topic and had this to say about it;

"Looking closer at the Infiniti TSB (ITB17-035) itself, it states that the failed injectors be replaced and also calls for the high pressure fuel rail, and the high pressure tube on the bank where the injector failed to be replaced at the same time. This seems to indicate that perhaps there is contamination related to the fuel rail that is causing the injector failures. We can theorize that metal material is coming loose inside the rail and causing many of the injector failures that we are seeing.

While it is not completely clear where this metallic debris is originating, nor are we suggesting that 100% of injector failures are caused by fuel rail material, we can say that it is extremely unlikely that the debris would be from the Red Alpha HPFP or any other aftermarket fuel components "

95175
 

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Discussion Starter #18
Except that's not how boost curves are calibrated, the car is only running at peak boost at very specific RPM ranges typically around 5500-5800RPM,
after-which it quickly drops off as the turbos are far outside their efficiency tables and only creating massive amounts of heat.

So even if the injectors are being pushed harder they aren't operating at 100% the entire time, so while failiures should
appaer they wouldn't be in the number we've witnessed. In fact AMS weighed in on this particular topic and had this to say about it;

"Looking closer at the Infiniti TSB (ITB17-035) itself, it states that the failed injectors be replaced and also calls for the high pressure fuel rail, and the high pressure tube on the bank where the injector failed to be replaced at the same time. This seems to indicate that perhaps there is contamination related to the fuel rail that is causing the injector failures. We can theorize that metal material is coming loose inside the rail and causing many of the injector failures that we are seeing.

While it is not completely clear where this metallic debris is originating, nor are we suggesting that 100% of injector failures are caused by fuel rail material, we can say that it is extremely unlikely that the debris would be from the Red Alpha HPFP or any other aftermarket fuel components "

View attachment 95175
Right, it is tapered and drops off roughly the last 1-1.5k rpm. Are you rrying to say the engine consumes more cc per minute at 5500rpm at 19psi vs 6500rpm at 14psi? What about the people having high rpm lean issues?

yup that is the article we refrenced earlier.
While it is not completely clear where this metallic debris is originating, nor are we suggesting that 100% of injector failures are caused by fuel rail material” not conclusive.
 

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People having high rpm lean issues have nothing to do with the injectors. It's because they are dropping fuel pressure with the factory fuel pump.
 

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As said above.
 
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