Factory 2011 Fuel Injector Flow Rate
04-09-2012, 08:42 AM
#11
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Five-o motorsports custom injector set on the way
25% more flow rate than oem (oem is 250 cc/min)
Installing this weekend
Will update as to swap, won't have any data unfortunately, but for what its worth
25% more flow rate than oem (oem is 250 cc/min)
Installing this weekend
Will update as to swap, won't have any data unfortunately, but for what its worth
04-14-2012, 06:07 PM
#14
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Glad to hear that it's working for you but keep in mind that when you buy larger injectors that there are more variables than just lb/min or CCs. The number of holes, high slope, low slope, and a number of other injector variables come into play. Also keep in mind that Ford uses a 39.5 pressure drop across the injectors whereas GM uses 42 (except some LS motors). I have no idea what Chrysler uses. If Chrysler uses a 19lb/hr injector at 58 psi then the Ford/Bosch 24 lb/hr injector is actually considerably smaller than the Chrysler variant.
Also bear in mind that when you increase an injector size and have no means to tune for it that the vehicle is dumping in more fuel even in a low load or idle state and may run excessively rich in these states and cause engine damage by washing down the cylinder walls.
Furthermore, Chrysler still isn't using a MAF even in this new engine and therefore the computer has NO IDEA that you've increased airflow to the motor and will not adjust load/timing/fuel accordingly. It will solely use the factory narrowband O2 sensors, BAP, and MAP sensors to determine basic running condition but these all hinge upon the Chrysler engineer's software model for airflow as programmed into the ECU.
Having said all that, I hope it all continues to work out for you!
Also bear in mind that when you increase an injector size and have no means to tune for it that the vehicle is dumping in more fuel even in a low load or idle state and may run excessively rich in these states and cause engine damage by washing down the cylinder walls.
Furthermore, Chrysler still isn't using a MAF even in this new engine and therefore the computer has NO IDEA that you've increased airflow to the motor and will not adjust load/timing/fuel accordingly. It will solely use the factory narrowband O2 sensors, BAP, and MAP sensors to determine basic running condition but these all hinge upon the Chrysler engineer's software model for airflow as programmed into the ECU.
Having said all that, I hope it all continues to work out for you!
04-15-2012, 01:40 AM
#15
JK Super Freak
Without checking/changing the fuel injector pulse width, injector duty cycle, fuel pressure, and fuel pump duty cycle, all in the tune, what you changed did little to nothing, or even worse, can give you issues you are not aware of.
04-15-2012, 04:53 AM
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The injectors I put in flow 25% faster than the factory, a really small increase that is still well within range. Also, they are a matched custom set.
If 2 more mpg is little to next to nothing, more please.
The engine is obviously getting more power from the fuel and achieving more efficient combustion.
If 2 more mpg is little to next to nothing, more please.
The engine is obviously getting more power from the fuel and achieving more efficient combustion.
04-15-2012, 07:06 AM
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Have you done a mileage check through simple addition and averaging? Ex..add"x"amount of gallons and record your mileage? The factory computer is just averaging your mileage...averaging.
I wouldn't trust the factory computation with different injectors...if you really want to know if your getting better mileage divide your number of gallons by the amount of miles you get out of said number of gallons.
I'm glad your being a Guinea pig for us but without a wide band or some histograms and data logging its all gonna be based on your butt dyno.
I personally am not so sure this will work like you want..Chrysler put 5w20 in these engines and sacrificed engine life to get an extra mpg or 2 for the EPA mandates...I'm sure Chrysler would have done some thing as simple as just putting different injectors in..especially if it didn't require any tuning changes...don't take this the wrong way...I'm not trying to flame you and I appreciate your willingness to try your theory on your own vehicle...good luck...keep us updated..subscribed!
I wouldn't trust the factory computation with different injectors...if you really want to know if your getting better mileage divide your number of gallons by the amount of miles you get out of said number of gallons.
I'm glad your being a Guinea pig for us but without a wide band or some histograms and data logging its all gonna be based on your butt dyno.
I personally am not so sure this will work like you want..Chrysler put 5w20 in these engines and sacrificed engine life to get an extra mpg or 2 for the EPA mandates...I'm sure Chrysler would have done some thing as simple as just putting different injectors in..especially if it didn't require any tuning changes...don't take this the wrong way...I'm not trying to flame you and I appreciate your willingness to try your theory on your own vehicle...good luck...keep us updated..subscribed!
04-15-2012, 08:26 AM
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Just filled up. Will go 1/2 tank and check.
Not a lot of what chrysler does makes sense
There are two competing schools of thought with regards to emissions.
One is to maximize engine efficiency and the other is to catalytically remove emissions which reduces engine efficiency. Chrysler uses double wall exhaust pipes at points near the cats to keep temperatures high and improve catalysis. I saw this first hand when I put the headers on. That and the fact that they run it very lean tells me which way they were thinking. The injector duty cycle was too long at higher rpms. Going 25% up in flow has stopped the lean codes that I was getting and was an educated guess based on going 10% richer with the stock injectors and hitting lean codes. Also considered the published gains from the ripp long tubes.
Definitely going to do the mileage check.
Not a lot of what chrysler does makes sense
There are two competing schools of thought with regards to emissions.
One is to maximize engine efficiency and the other is to catalytically remove emissions which reduces engine efficiency. Chrysler uses double wall exhaust pipes at points near the cats to keep temperatures high and improve catalysis. I saw this first hand when I put the headers on. That and the fact that they run it very lean tells me which way they were thinking. The injector duty cycle was too long at higher rpms. Going 25% up in flow has stopped the lean codes that I was getting and was an educated guess based on going 10% richer with the stock injectors and hitting lean codes. Also considered the published gains from the ripp long tubes.
Definitely going to do the mileage check.