Living with my Sniper fuel injected 78 NYB

[73 T&C]

It’s been almost a year since it was installed so I thought I’d start a separate thread as to how this radical change (upgrade?) is going.

The good:

Starts every frogging time
Runs a little smoother and cooler
Gas mileage about the same.
No more electronic lean burn ignition
A lot of things left to try to make better


The bad:

Installation done right was expensive (you can see the initial install in my other thread)
Took a while to tune in.
Throttle Tip in response took a while to equal and then surpass carb.
Now I want to install the timing control

The ugly…

Still trying to find an acceptable place to put the monitor. Thinking ashtray.

Todays project: stagger the throttles so as to open in steps.

The sniper comes with two holes for connecting the front two barrels with the rear two linkage.

Took out the linkage and bent it so as to work the rear throttles after 1/2 way point of the front pair. Like a mechanical secondary.

Took about 1/2 hour after install for the computer to relearn what was happening and adjust itself to a more progressive amount of air. Needed to adjust the initial throttle setting up a bit to get the idle air control to work at around 11%. Monitor provided with Sniper is an invaluable tool.

Here’s a picture of the “adjusted” linkage.

Here’s the original set up as it went in.

Here’s a detail of the linkage

The original style linkage (silver link below throttle cable and cruise cable) set up shown above did not work with the air cleaner and cruise control in place due to interference. This link was just bent to 90 degrees at the same bend point and moved to the next hole up.

Cruise control was moved to the outboard end of the alignment pressed pin. It works fine now.

Next project: clean up the adapter plate where the original throttle and cruise control are connected….. now that it actually works.

 

[75LandYacht]

Good stuff Javier…

 

[commando1]

You're gonna find a wrecked Tesla, break out the tape measure, and start all over from scratch before you finish your foolishness with this.

 

[73 T&C]

Today I reworked the cruise control and throttle cables for smoother operation.

Took a small crowbar to it to move it about 1/4 outboard for better alignment.

Cruise now engages very positively and works perfectly. However, the set button records the speed that is set but does not activate the system. I have to push “resume” and it activates. No idea what the issue is. Brake and set button will deactivate it. Let me look around here to see if anyone has written about this or similar issues.

Car starts fine but putting it gear seems to fluster the system and the fuel air goes to 19 for a split second. But then settles in fine. Looking into that.

Increased the acceleration f/a to 12.5. More responsive of the line…… after fully warmed up.

Here’s the latest readings from the sniper control box:

MAP, kPa is: Mass Airflow pressure
CTS is: Coolant Temp Sensor, 200 is about average after warmup
TPS is: Thottle Position Sensor, idle no throttle is 0
AFR is: Air/fuel ratio. 13.5 to 1 is a little rich but less and it has more to make up of line and tip in of throttle suffers a bit.
Battery/Volts is: self explanatory
Ign Timing is: ignition timing… next upgrade.
MAT.F is Mass Air Temp in degrees F. 99 is a lot cooler than engine compartment air due to outside air ducts. Before ducts it was a source of pinging problems.
IAC pos % is Idle Air Control position as a percentage of available idle air which can be added. Sniper literature says to tune it to 11 at idle.
RPM… do I have to say it?

 

[73 T&C]

You're gonna find a wrecked Tesla, break out the tape measure, and start all over from scratch before you finish your foolishness with this.

Well at least I got rid of the Thermoquad……

 

[fury fan]

For all you future/unfamiliar readers, finding this discussion a few years from now, and wondering how we got here.

78 NYB Holley Sniper install.. the end of my lean burn fun

 

[Rick T]

It’s been almost a year since it was installed so I thought I’d start a separate thread as to how this radical change (upgrade?) is going.

The good:

Starts every frogging time
Runs a little smoother and cooler
Gas mileage about the same.
No more electronic lean burn ignition
A lot of things left to try to make better


The bad:

Installation done right was expensive (you can see the initial install in my other thread)
Took a while to tune in.
Throttle Tip in response took a while to equal and then surpass carb.
Now I want to install the timing control

The ugly…

Still trying to find an acceptable place to put the monitor. Thinking ashtray.

Todays project: stagger the throttles so as to open in steps.

The sniper comes with two holes for connecting the front two barrels with the rear two linkage.

Took out the linkage and bent it so as to work the rear throttles after 1/2 way point of the front pair. Like a mechanical secondary.

Took about 1/2 hour after install for the computer to relearn what was happening and adjust itself to a more progressive amount of air. Needed to adjust the initial throttle setting up a bit to get the idle air control to work at around 11%. Monitor provided with Sniper is an invaluable tool.

Here’s a picture of the “adjusted” linkage.

View attachment 614465

Here’s the original set up as it went in.
View attachment 614474
Here’s a detail of the linkage
View attachment 614475
The original style linkage (silver link below throttle cable and cruise cable) set up shown above did not work with the air cleaner and cruise control in place due to interference. This link was just bent to 90 degrees at the same bend point and moved to the next hole up.

Cruise control was moved to the outboard end of the alignment pressed pin. It works fine now.

Next project: clean up the adapter plate where the original throttle and cruise control are connected….. now that it actually works.

View attachment 614484

I have the same system on my 78 New Yorker with the # matching
440 however, it’s built and has a different manifold. Without getting into too much detail once we got it dialed in and adjusted. It’s great I love it it’s been on for over two years. I have my controller setting in my ashtray cable going through the glove department so if I need to adjust it, I just pick it up from the ashtray. We skipped the self learning and tuned it how we wanted to and locked it in. Here is a picture of it before we built the engine. The other picture is after the rebuild.

 

[73 T&C]

I have the same system on my 78 New Yorker with the # matching
440 however, it’s built and has a different manifold. Without getting into too much detail once we got it dialed in and adjusted. It’s great I love it it’s been on for over two years. I have my controller setting in my ashtray cable going through the glove department so if I need to adjust it, I just pick it up from the ashtray. We skipped the self learning and tuned it how we wanted to and locked it in. Here is a picture of it before we built the engine. The other picture is after the rebuild.

View attachment 616240

View attachment 616241

I’m thinking edelbrock manifold as well. Maybe along with the sniper ignition.

 

[Rick T]

I’m thinking edelbrock manifold as well. Maybe along with the sniper ignition.

I do have the complete sniper system & I love it.

 

[73 T&C]

As I’ve come to enjoy the reliability of my new sniper, I’m also enjoying dialing it in.

One thing I did recently was change the linkage to progressive opening of the throttles. The front two open first followed by the rear at about 30% throttle (as measured by the sniper itself) picked up another mile net per gallon to a whopping 9 mpg! Mostly city driving. Put it on the highway for a client meeting in the next county and got an honest 15 MPG. I attribute this to the progressive linkage change. This change also came with a change in the programming to progressive throttle setting. It allows for selection of when the rear two injectors come on. I set it at 30% throttle to coincide with the linkage. My initial setting was 45% since the rear were only just starting to open at 30%. I figured that bringing on the extra injectors too soon might bog the engine but instead noticed it had a mild flat spot. So 30% it is.

Of course, I had to fiddle with the fuel settings. Dropped the fuel enrichment by temp a bit (works like a choke on a carb) for better mileage with no resulting detriment to the drivability. Meaning I was dumping to much fuel into the engine.

Whereas before I had to really be really careful with the throttles or suffer unwanted acceleration (such things are now possible), now I can give it a bit of throttle , say up to 15%, for a nice smooth and rather strong pull away. Even at that level of throttle I find myself pulling out ahead of those around me. Highway cruising at 65 mph has the throttle at anywhere from 7 to 17%

The timing is also now a bit more advanced. Started at base 10 degrees and have been bumping up 2 degrees at a time. 16 degrees seems the be the sweet spot for this engine. Distributor set at 18 degrees base was making it ping under more than normal load… i.e. I was goosing it.

Whereas before, with the two sets of throttles opening simultaneously the initial fuel pressure/speed of throttle movement was set high at initial throttle movement speed off idle, this was reduced to avoid a hesitation issue.

Of course the above has to do with the engine I had built and is specific to it. It’s a good record of what I did in tuning it in.

And since no post is complete without a picture….. here’s a picture of her in daily driving duties.

 

[commando1]

As I’ve come to enjoy the reliability of my new sniper, I’m also enjoying dialing it in.

One thing I did recently was change the linkage to progressive opening of the throttles. The front two open first followed by the rear at about 30% throttle (as measured by the sniper itself) picked up another mile net per gallon to a whopping 9 mpg! Mostly city driving. Put it on the highway for a client meeting in the next county and got an honest 15 MPG. I attribute this to the progressive linkage change. This change also came with a change in the programming to progressive throttle setting. It allows for selection of when the rear two injectors come on. I set it at 30% throttle to coincide with the linkage. My initial setting was 45% since the rear were only just starting to open at 30%. I figured that bringing on the extra injectors too soon might bog the engine but instead noticed it had a mild flat spot. So 30% it is.

Of course, I had to fiddle with the fuel settings. Dropped the fuel enrichment by temp a bit (works like a choke on a carb) for better mileage with no resulting detriment to the drivability. Meaning I was dumping to much fuel into the engine.

Whereas before I had to really be really careful with the throttles or suffer unwanted acceleration (such things are now possible), now I can give it a bit of throttle , say up to 15%, for a nice smooth and rather strong pull away. Even at that level of throttle I find myself pulling out ahead of those around me. Highway cruising at 65 mph has the throttle at anywhere from 7 to 17%

The timing is also now a bit more advanced. Started at base 10 degrees and have been bumping up 2 degrees at a time. 16 degrees seems the be the sweet spot for this engine and distributes set up as 18 was making it ping under more than normal load… i.e. I was goosing it.

Whereas before, with the two sets of throttles opening simultaneously the initial fuel pressure/speed of throttle movement was set high at initial throttle movement speed off idle, this was reduced to avoid a hesitation issue.

Of course the above has to do with the engine I had built and is specific to it. It’s a good record of what I did in tuning it in.

And since no post is complete without a picture….. here’s a picture of her in daily driving duties.

View attachment 620023

I'm completely lost on what you're doing dialing in that sniper, but I'm impressed .

 

[73 T&C]

Monitor found a home:

After having it the glove box, I didn’t like that I had to open it to see the monitor and then remember to close it to avoid the drain on the battery.

So I propped it up between the A/C vent under the glove box and my aftermarket cup holder

And the glove box door opens without interference.

It also has the added benefit of stabilizing the cup holder…. Which is also very good.

 

[73 T&C]

Car runs fine. Gas mileage kind of sucks because I like goosing it every now and then. About 8-9 mpg in the city.

Highway… I get at least double at 70mph.

 

[70bigblockdodge]

Well at least I got rid of the Thermoquad……

Blasphemy, lean burn yes, a reworked TQ and it would be good. Glad the sniper is working for you. Lot of people with carburetor problems still have problems with the sniper. It only cleans things up, not a miracle maker.

 

[fury fan]

I'm completely lost on what you're doing dialing in that sniper, but I'm impressed .

Actually, you probably understand it better than you think.

Tuning EFI requires knowing how an engine runs and what it needs when conditions are changing.
Airflow is the key to the fueling and timing on any engine - whatever it wants with a carb, it wants with EFI.
For instance, the airflow changes and fueling requirements when the throttles crack open are unchanged.

So - if you can understand what the engine is lacking, you find out what parameter that is in the ECU, and you adjust it.
You just need to learn some definitions to correlate the terms.
It's like those old-school experts bending a tab here/there, or maybe lengthening a slot, or changing a jet vs changing a metering rod to one with a different step.
But the big (best) difference is if you don't like something, you can change it back easily, as many times as you want.

Just like the optometrist does.
And if you can't really tell the difference in your right foot or seat of pants, the self-tuning can make those subtle changes.

 

[bikemobile]

Ashtray mount works well in my 63’ 880