i already have another thread about an injector and turbo combo, but my thinking has changed a bit and the thread has died. heres my question: with my edge unit and a phat shaft 62 turbo, what sized injector would be the most beneficial for mileage but still lighting the turbo when empty and towing? im wanting to step up from my rv275's, but dont want to lose mileage. and i need a turbo so i can have more useable power when towing. most people suggest either 110hp or 150 hp injectors with the turbo and box, but they play [empty] and arent as concerned with mileage.

thanks,

jeremy

 

Mileage is important to me, and I posted in your other thread that my M4s give fuel mileage just as good when the truck was stock-- sometimes even better.

I count on 16 pure city, 20 pure hwy, and 18.x mixed.

 

i was looking at that turbo but didnt want to go over mach 1.6s and a adrinalen. turbo to big for that?

 

I get 14-15 in town and 20-22 on the highway with my 4's.........depending on the foot. Thats sea level, 3.55 gears and playing with the box/s (empty)......Brad

 

I average between 19-20 with mostly highway with my m4's definitely helped with mileage.
Andrew

 

so if i went down in injector size, my mileage would go up, correct? since its flowing/using less fuel? but i also know that more horsepower (too a point) means less work for the engine to perform to do the same job. and another thing - is it better to use more fueling from a box thru a smaller injector hole or using less fueling from a box (using lower levels) and pushing that fuel through a larger injector hole??? thats what im trying to figure out for best mileage and most complete fuel atomization.

thanks,

jeremy

 

turn the box down except for play and get something 100-150 like you stated
I had some New era diesel 150HP injectors and were pleased with them, now running mach2 105hp. they are good too.

 

i'd try industrial injection 3 flows. They are about 100 horse and i liked mine when i had thm. Good price too.

 

basically smoke = loss of mpg. keep it easy on the throttle. I did not notice a difference in mpg on the 105 or 150hp sticks.

 

the other thing i worry about is spoolup.

i know turning the box down and using larger injectors for play would be ideal for power and all, but im talking about efficiency. i like using one horsepower level for driving and able to turn it back down for when i hook up to a load. and especially with fuel prices the way they are now, i dont play a whole lot anymore. im just looking for the best injector for mileage, but gaining the most power without going backwards on mileage. im not a big fan of smoke at all, and want the best atmoization. thats why im questioning the 150's. thats why im even wondering about just settling for mach 1.6's. but then im concerned with spoolup with the lower i go. sure i want the most power i can get, but now its more about mileage. that and the most complete fuel atmoization.

thanks,

jeremy

 

with everything in my sig im getting 16-18 city and 22-28 highway since most of my driving is highway my avg mpg on the console shows 23.8

 

Smaller injectors don't necessarily improve mpg. The largest variable is driver aggressiveness. Some guys can't get 16mpg from a stock injector-- others get 20+ with a Mach 6. The amount of fuel used is a function of how much HP the engine is being asked to make, and how efficiently it can make that HP. Actual injector flow capacity means very little by itself for mpg. Atomization, spray angle, rate of discharge, etc matter much more.

Not true. The work the engine must do is the work the engine must do. It doesn't matter if you have 500hp available or 150hp available-- if you have 100hp worth of work, then the only relevant discussion is how efficiently you can make 100hp--not 150hp or 500hp.

In general, a faster rate of discharge will be more efficient (to a point) because it produces a quicker rise in combustion temp and takes less time to deliver a given amount of fuel.

The question is: does the larger injector have poorer atomization that offsets the advantage of the faster rate of discharge?

A higher flowing injector requires less duty cycle on the pump to flow a given amount of fuel.

There is a point where duty cycle increases will burn fuel more efficiently than injector flow rate increases. Where that point exists is anyone's guess.

So, the point of my non-answer to your question is that sometimes it's better for mpg to have a larger injector and sometimes it's better to increase pump duty cycle.


The thing that makes this such a tough question to answer is that the "ideal" injector only exists for a narrow set of conditions of fuel flow, timing, and engine load. Everything else is a compromise.--jh