FirstFJ60
SGT. Lincoln Osiris
Im just curious why wasnt there any mpg improvements when EFI should be more efficient than a carb?The Sniper replaces the carburetor
No mileage improvements
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Im just curious why wasnt there any mpg improvements when EFI should be more efficient than a carb?The Sniper replaces the carburetor
No mileage improvements
Not necessarily. It’s a one size fits all system.Im just curious why wasnt there any mpg improvements when EFI should be more efficient than a carb?
It’s not the same as direct injection where each cylinder gets its own squirt of fuel. It functions as a carburetor but is controlled by a computer rather than vacuum. The intake is designed for a carb which requires a pulse to keep things flowing. This may effect the sniper’s efficiency to some degree but I don’t know enough about those fluid dynamics. Cleaning up a rough casting would probably do more for fuel efficiency than anything else. Also, running the correct oil will improve MGP.Im just curious why wasnt there any mpg improvements when EFI should be more efficient than a carb?
Thanks for the break down...makes sense. Im just trying to justify the Holley Sniper when my carb works great w/o being desmogged.It’s not the same as direct injection where each cylinder gets its own squirt of fuel. It functions as a carburetor but is controlled by a computer rather than vacuum. The intake is designed for a carb which requires a pulse to keep things flowing. This may effect the sniper’s efficiency to some degree but I don’t know enough about those fluid dynamics. Cleaning up a rough casting would probably do more for fuel efficiency than anything else. Also, running the correct oil will improve MGP.
starting and running sideways are definite advantages. in really cold weather you are on the go much quicker when finally tuned. think of it this way, if merely adding FI added MPG, they wouldn't have had to redesign entire engines.Thanks for the break down...makes sense. Im just trying to justify the Holley Sniper when my carb works great w/o being desmogged.
That idle AFR is pretty rich. I think mine is 14.0-14.2.My O2 sensor is in the "test pipe" cat' area at 1:30 position. View attachment 3182228View attachment 3182229
What's whis fuel prime multiplier?
To me 5 minutes to swap in another Bosch unit. The wires are the perfect length to avoid the exhaust and throttle stuff. The poor girl might be suffer from "short distance driving syndrome". I've been averaging 6.1 miles per day.
Im just curious why wasnt there any mpg improvements when EFI should be more efficient than a carb?
Yes, way more rich than I thought it should be. This was recommended by Holly tech because of stalling issues after engine braking before a stop. I have yet to get it tuned by the laptop method. I'm getting some smoke from worn valve seals now that I suspect is playing hell with the O2 sensor. Sniper can't get to set AF levels, varies from too lean to too rich daily. I got a spare head to get prepped, that had better fix it.That idle AFR is pretty rich. I think mine is 14.0-14.2.
It's more efficient at turning bad gas mileage to more power. If you are used to driving a smogged 2f, you will appreciate the difference. If your engine doesn't have even and good compression, EFI is not a good idea. The carb is more forgiving and EMP resistant. Plus you have a cool lighted choke cable to scare the kids.Im just curious why wasnt there any mpg improvements when EFI should be more efficient than a carb?
naa.. thats fine. its just idle, and that fuel will keep the o2 from hunting around and going lean with the s***ball uneven airflow on the 1930's manifold design when you come off a long slow deceleration. keep in mind if you put a modern oem engine management system on this engine, the airflow is so uneven cylinder to cylinder at any given cycle, it would likely go "robbie the robot" and self destruct. A good engine may be .5 higher, but these aren't good engines when new.That idle AFR is pretty rich. I think mine is 14.0-14.2.
Me too. I mean, I only have one, but still, it’s all stock settings.All my Snipers are run on the stock settings.
I sometimes get the stalling when I stop with a cold engine.
I modified the stock linkage arm for direct linkage and have great tip in and 70% WOT. I did add a return spring. It works very well both crawling and on the road. I can feel the engine twist in the mounts corresponding to pedal induced torque.A couple additional things i'll note that were fighting here, is the amount of RPM band were dealing with, and volume of air required for the power produced.
first, the sniper (at least my "2bbl" model) comes set up, and is expected to be utilized, on an engine that has 40% more usable rpm. I tried making a map that would mirror the expected basic V8, but with an RPM band much stumpier, and that level of detail wasnt appreciated by this engine, it would hunt like crazy.. What is running great, is a map barely more complicated than the "idle, cruise, wot" it comes with just to get the damn thing to turn over. i actually suspect many people just leave it at that factory setting, and the blind squirrel may have found a nut with that approach.
WOT on this is for a 300hp v8, not a 120hp 6, of similar volume. tip in is way to fast, so i made a lever arm i attached to the linage with a 5 different positions so i could limit the air more. i think if i recall i settled on about 70% actuation of the valves. it also provides a control advantage when you have the gears i have. I was going to tear apart a gm tbi for the cable cam, but i didnt want to risk breaking the holley as there's some press fit s*** on it.
I have one that does it pre-160. The second it hits 160 it won’t do it.Me too. I mean, I only have one, but still, it’s all stock settings.
I sometimes get the stalling when I stop with a cold engine. But I’ve found that if I just don’t push in the clutch until I absolutely have to to, I can avoid the stalling.
That's what Holley tech asked me to do.I have one that does it pre-160. The second it hits 160 it won’t do it.
That one is at 680 rpm though. Looking above at the guys with the big brains maybe I’ll bump it to 750.