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I Finally Did It.....EFI

I think that approach will cause you problems. The EFI system uses the temp sensor to control the choke so if it doesn't see hot water right away you'll have a "stuck choke". You can try it if you want but I think you'll be changing it once you see what happens.
I see what you're saying,... I'll keep that in mind when I try it, then I guess it's back to the water pump drill and tap if it doesn't work. My thinking is the pee hole will let enough through but I guess you're saying not quick enough for the sensor? I'm installing a Holley Sniper.
 
Here is a fuel graph after adding learn table and some smoothing.
20210127_105726.jpg
 
I would also like to add that this has been a very informative discussion. :thumbsup:

My question is what intake are you running on your engine?
 
I have not gotten as far as adding a user-generated learn table to my tune so I have a question - what is the 37.482% value at the top? If that's the amount of change from the original config, that seems like A LOT for any data point. If not, then do you know what that number signifies?
 
I have not gotten as far as adding a user-generated learn table to my tune so I have a question - what is the 37.482% value at the top? If that's the amount of change from the original config, that seems like A LOT for any data point. If not, then do you know what that number signifies?

That is a VE number. That data point is for 500 rpm and 20 kpa which is a point on the map that is impossible to reach.
 
I'm assuming you have been working on this since Dec. and hopefully you have been successful. I'm in the middle of installing this same Holley EFI on my 440. What I'd like to ask you is where did you end up putting the temp. probe? I have Digital gauges and the only spot I can see for a mounting location already has the probe in it.

My aluminum water pump housing has two threaded temp sensor holes. A small one 1/8 npt and a larger one 1/2 npt (needs a brass reducer as 1/2 is way too large for the Sniper sensor).
 
I finally gave in to the dark side. Purchased a Holley Sniper EFI for my GTX. I've been having a weird lean pop at mid-low rpm that I just cannot tune out on my Edelbrock AVS carb. Said "F' it and bought it.

I already have the Holley Sniper EFI gas tank with 255 Walbro pump and an o2 sensor installed so it should make for an easy swap. I went with the EFI 4150 550-516 unit. 800cfm and good to 650 hp. Has a built in pressure regulator and is what sold me on it.

Going to document my install as I go. I'm curious as to how my throttle and kickdown stud fit. I am assuming I'll have to tweak it.

View attachment 1037855
 
New here trying to do a Sniper on my 67 Coronet.
Got questions. 1, Where is best source for key on and crank 12v?
2, Where is best to mount the Walbro inline pump?
Not much room
What works? Pictures appreciated.
I'm really bad using the site here. Help
[email protected]

Thanks
TomH
 
New here trying to do a Sniper on my 67 Coronet.
Got questions. 1, Where is best source for key on and crank 12v?
2, Where is best to mount the Walbro inline pump?
Not much room
What works? Pictures appreciated.
I'm really bad using the site here. Help
[email protected]

Thanks
TomH

There is no source for key on and crank 12 volts in a Mopar, you have to build it yourself. How you build it depends on how skillful you are. I prefer to start with a reproduction engine wiring harness which I take apart and redo. I eliminate the ballast resistor from the harness and tie IGN 1 and IGN 2 together to power the Sniper.

As for your second question, I'd recommend putting the pump inside the tank. You can buy a tank from Holley for your Coronet: https://www.holley.com/products/fuel_systems/fuel_injection/sniper_efi/fuel_tanks/parts/19-183
 
3 month update....

Everything is running great. No issues. I played with smoothing the fuel tables and haven't had any negative effects. AN fittings are still tight. I've been driving it to work for the past month and a half. Gotta get my drive time before we get +100 temps.
 
3 month update....

Everything is running great. No issues. I played with smoothing the fuel tables and haven't had any negative effects. AN fittings are still tight. I've been driving it to work for the past month and a half. Gotta get my drive time before we get +100 temps.

What does the learn table look like? You want the learn table to be all small numbers, everything should be less than 10. If everything is less than 10 then the system is dialed in pretty well and you can reduce the learn percentages. If not, then transfer learn to base and keep driving it until all numbers are less than 10.

Once you get a tune that is working great for you then you can save that tune under another name as a backup. I sometimes turn off closed loop operation for the back up tune so if you get stuck somewhere with a bad O2 sensor you can plug in the back up tune and drive home without the O2 sensor. Having a back up tune in your ECU can save you a tow bill or a long walk home.
 
What does the learn table look like? You want the learn table to be all small numbers, everything should be less than 10. If everything is less than 10 then the system is dialed in pretty well and you can reduce the learn percentages. If not, then transfer learn to base and keep driving it until all numbers are less than 10.

Once you get a tune that is working great for you then you can save that tune under another name as a backup. I sometimes turn off closed loop operation for the back up tune so if you get stuck somewhere with a bad O2 sensor you can plug in the back up tune and drive home without the O2 sensor. Having a back up tune in your ECU can save you a tow bill or a long walk home.

Thanks Andy. The numbers looked fairly small for the most part. I'll have to pull it back up and double check though. I'll save it too.
 
Sweet!

Now that you some time with it, how do you like it compared to the carb

Understand this isn’t a fair comparison to carbs in general cuz the carb wasn’t happy

Mostly in interested in perks/convenience like reduced warm up time, mpg(?), drivability, and if you have some or foresee trade-offs

(Hi all, I know “nobody gets these for MPGs”, but if it extends range per tank significantly that’s a nice perk to most; only takes a few mpg improvement)


A buddy wants to do it with his Camaro


Thanks!

And congrats again for knocking this thing out
 
Sweet!

Now that you some time with it, how do you like it compared to the carb

Understand this isn’t a fair comparison to carbs in general cuz the carb wasn’t happy

Mostly in interested in perks/convenience like reduced warm up time, mpg(?), drivability, and if you have some or foresee trade-offs

(Hi all, I know “nobody gets these for MPGs”, but if it extends range per tank significantly that’s a nice perk to most; only takes a few mpg improvement)


A buddy wants to do it with his Camaro


Thanks!

And congrats again for knocking this thing out

Cold starts are simple. Key on until the handheld loads (2-3sec) then one crank and it fires. The cold idle is fantastic, you can go immediately without nursing the throttle.

Driving is smooth, throttle instantaneous. Good idle manners. Ease of tuning is a great feature.

Only trade off I can think of is the price vs. carb. With efi there is little to no fuel smell, better tuning and more precise. Pressurized fuel system = no evaporation from system.
 
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