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I Finally Did It.....EFI

Thanks for keeping us updated in this thread. This will be the way I go when I get the rest of my motor completed.

My question is, did you have to do the tuning or did you do the tuning because you didn't want to wait for the EFI to do it?
 
Thanks for keeping us updated in this thread. This will be the way I go when I get the rest of my motor completed.

My question is, did you have to do the tuning or did you do the tuning because you didn't want to wait for the EFI to do it?

I added the learn table to the base table because that is what I believe needed to be done. It probably didn't make much difference but it cleaned up the tune. Easier to save as a tune without the clutter. And I manually smoothed the fuel curve. And it was a good learning experience getting hands on with the program.
 
@threewood

What manifold vacuum are you seeing at idle and like during cruising speed?
I was looking at that today and wonder how to convert that as the MAP pressure is shown in Kpa.
Since this is "absolute" pressure this is not shown as a negative reading.
So if i am right, 70kpa MAP pressure on the EFI screen is just over 20 In/Hg vacuum?

Because i am seeing around 70 KPa (20 in/hg) MAP at idle and around 40 KPa (12 in/hg) at 50mph cruising.
Strange thing is that i always seen around 7 in/hg on the vacuum gauge when i was playing around with a carb.
Think i am missing something here because those numbers does not seem right..
 
@threewood

What manifold vacuum are you seeing at idle and like during cruising speed?
I was looking at that today and wonder how to convert that as the MAP pressure is shown in Kpa.
Since this is "absolute" pressure this is not shown as a negative reading.
So if i am right, 70kpa MAP pressure on the EFI screen is just over 20 In/Hg vacuum?

Because i am seeing around 70 KPa (20 in/hg) MAP at idle and around 40 KPa (12 in/hg) at 50mph cruising.
Strange thing is that i always seen around 7 in/hg on the vacuum gauge when i was playing around with a carb.
Think i am missing something here because those numbers does not seem right..

My idle vacuum has always been around 13-14 in/hg. I'm not sure what the conversion is from kpa.
I just went back and looked at my start up video and the kpa number is around 46 which is right at 13.5 in/hg according to a conversion I found on line.
 
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@threewood

What manifold vacuum are you seeing at idle and like during cruising speed?
I was looking at that today and wonder how to convert that as the MAP pressure is shown in Kpa.
Since this is "absolute" pressure this is not shown as a negative reading.
So if i am right, 70kpa MAP pressure on the EFI screen is just over 20 In/Hg vacuum?

Because i am seeing around 70 KPa (20 in/hg) MAP at idle and around 40 KPa (12 in/hg) at 50mph cruising.
Strange thing is that i always seen around 7 in/hg on the vacuum gauge when i was playing around with a carb.
Think i am missing something here because those numbers does not seem right..

You are missing something, those numbers are not correct. 100 kPa is pressure at sea level so 70 kPa is fairly high pressure. It is not anything close to 20 inches of vacuum, probably half of that. You can look it up if you need to know the exact numbers.
 
You are missing something, those numbers are not correct. 100 kPa is pressure at sea level so 70 kPa is fairly high pressure. It is not anything close to 20 inches of vacuum, probably half of that. You can look it up if you need to know the exact numbers.

Yes the way i was thinking does not make sense, because you need to work with the KPa that is missing from atmospheric pressure.
The 100KPa atmospheric pressure is reduced to 70KPa (in my case), so there is 30KPa loss.
This 30 KPa would be the vacuum reading, 1KPa = 0.3 in/Hg, so that would give me around 9 in/Hg manifold vacuum at idle which is normal for my car.
At cruise 40KPa MAP, a loss of 60KPa, would be around 18 in/Hg.

In threewoods case, 46 Kpa would be around 16 in/Hg, if at sea level.
I live slightly below sea level so i am always getting a good fill :D
 
I've been off these forums for awhile, I personally had major issues with the Holley Sniper EFI system. Multiple Injector related issues and ECU failure within 1,000-miles, being one of the first to install these units, I've seen hundreds of failures since these were introduced on that specific FB group, Holley updated firmware regularly but never would offer spare injectors or an ECU. You'll see I was fairly prominent before being banned off FB on the Holley Sniper EFI group, created the parts store - spare parts replacement file to keep people who did experience issues (regularly), back on the highway and not waiting for Holley. I even talked to AndyF here originally, because Holley was cutting the Hyperspark distributor shafts too short (383/400 models) which created very little engagement in the oil pump drive gear. You wouldn't know it unless you physically measured and compared it against an OEM unit, as it had an 1/8" engagement.

There is very little to no economy increases with EFI alone over a well-tuned carburetor, the only major increase you'll see is if you allow timing control, which is relatively no different than vacuum advance on a carbureted engine - adding timing during cruise.

My advice - run a fuel pressure regulator, the internal unit is prone to failures. Don't run the external Walbro GSL392 pump the kit ships with, run an in-tank or 'submerged' fuel pump and make sure to carry a spare for a long road trip. Like everything, 100-micron fuel filter pre-pump and 10-micron fuel filter post pump. Find my file on the FB group to purchase all the user-serviceable parts (available from any local parts store or Rock Auto) for the unit and keep them in the trunk, you'll likely need one in the future and will be a lifesaver. If you have a Gold unit, some of the paint is known to flake off internally on the FPR side, it's a good idea to verify after a month or so that everything is still looking clean internally.

I'm back to tuning carburetors with a Wideband 02 sensor. I'm all for EFI, but factory OEM EFI systems. If I were to do it all over again, it would be a Dominator EFI setup with the ECU in the car, and a spare ECU / Fuel Pump / Injectors in the trunk. By that point though, I'd just purchase a GEN III Hemi with a 'Plug & Play' OEM Mopar ECU package to control it.
 
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First hiccup.

Driving home from work and car stalled. Showed high afr, still cranks. Get out, pop hood look at wiring and fuel lines.

Walk to the back to see if there is any vacuum in the tank and smell gas. Look under and it's soaked. Crawled under and....if you remember the rubber efi line I left on because of sealing issues with the an fitting.... Well, it popped off. Kind of an easy roadside fix. Tightened the clamp and drove home without issue.

I ordered a new 6an 1/4npt so I can install the an hose back on and give me more peace of mind.
 
First hiccup.

Driving home from work and car stalled. Showed high afr, still cranks. Get out, pop hood look at wiring and fuel lines.
I warned you that EFI was going to give nothing but problems. :poke:

I'm just kidding, of course. It's good to see that the system is working out.
 
Here is a B body with a Sniper that I just worked on.

DSC_4560 (Large).JPG


DSC_4560 (Large).JPG
 
Success!

Crawled under today and got to it. No more rubber lines and clamps. Used an Earls -6 to 1/4 npt fitting. Fired it up and no leaks. Best part was being able to just loosen the tank to get to the fittings.
20210416_174652.jpg


I inspected the Summit fitting and compared it to the brass barb fitting. There was much less taper on the Summit fitting. No wonder it wouldn't seal. In the trash!
20210416_174527.jpg
20210416_175427.jpg
 
Looking good. Yep, I've run into the poorly made fitting problem before. I typically buy parts from several different vendors these days just to increase the odds that I'll have some parts that work when they show up.
 
You sure that black fitting is NPT? To me it looks parallel thread (BSPP)
Looks like between hex and thread is place for an O-ring as well.
 
You sure that black fitting is NPT? To me it looks parallel thread (BSPP)
Looks like between hex and thread is place for an O-ring as well.

It was shipped as 1/4 npt. Bought 2 of them, one for the return and one for the feed. That one pictured leaked bad, like a running drip. Threads are certainly wrong. If you go back to where I installed it originally I mentioned it being closer to a bulkhead, or straight thread fitting.

Big takeaway is to buy name brand parts.
 
Summit fitting are trash IMO, I tried them twice and they failed both times I only use Fragola fittings now.
 
I used a combination of Russell Twist-Lok and Aeroquip hose and either Russell, Aeroquip or XRP fittings. Cost a small fortune but no leaks. No rubber hose, no worm clamps, not at 60 psi.
 
BTW, I finally got my laptop hooked up to the Sniper ECU two days ago. Just for fun, I updated the Sniper firmware from V15 to V26 today. Had a little bit of a scare when something stopped the flash in the middle and I had to cycle the key. Turning it back on I almost blindly tried to start the car and there was no fuel pump. Crap! Don't remember what I did to get it back on track but eventually the flash resumed and finished installing. I think the laptop went to sleep and dropped the connection? IDK. When it was completed everything was back to normal. Whew.

After that, a light went off in my head today regarding the software. I will admit that up to this point I was clueless about how to navigate it. I've had a few cold start and stalling issues recently and decided it was time to try and iron things out. After reading through the instructions in the 49 pg. PDF, I got into the software and found myself building some tables. I can now see what I was missing by not getting into this earlier. Guess I was just happy the car was running OK and didn't feel the need to mess with it.

You really can't just let the thing tune itself and endlessly learn. By building your own config files you can see how crude the base cals are. Couple that with any mechanical issues like exhaust leaks and you'd be so far out in left field you wouldn't be able to see home plate. Regardless, my car seemed to be running decently enough so it was eye opening to see how much room for improvement there is.

Keep up the good work there 3 Wood.
 
You dodged a bullet there. You have to turn off your sleep setting when doing an upgrade or else you can lock up the Sniper. The best way to upgrade a Sniper is to put the new file on the SD card and then upload it from the hand held device. That way you don't run the risk of locking things up.
You are correct that the prebuilt tables are very crude. They work okay for a mild engine but they really need to be adjusted for a performance engine. The other thing to think about is the creation of a "locked" tune once you have the tune where you want it. You can also build a "limp home" tune that allows you to drive the car home if the wide band sensor goes bad. Holley doesn't tell people how to do these things but people should take the extra steps if they can. A few minutes time up front can save you from a long walk home.
 
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