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Went back to a carb

Just checking in on this picture....I cannot see clearly enough if you have a dedicated return line going back to the fuel tank.
Now, just in case you do have the correct flow and return lines installed....this advice might be useful to anyone else contemplating a shortcut. :)
There isn't a return line at the carb. The bottom port of the fuel regulator is a return line. If fuel perc becomes an issue as the weather warms up I may have to explore another return line
 
my long time Mopar friend in Phoenix in the Mopar club has said numerous guys are ditching the EFI system, because they are getting tired of being broken down on the side of the road. esspecially when it is 110+ outside.
Very Interesting,,,
 
Sorry you had troubles but I will never go back to a carb on a street driven car. Frankly I know nothing about FI Tech but my Holley Sniper is great. Car runs light years better than with a carburetor, its laughable how much better it is. Yes, had some teething issues at first but it’s all good now, I don’t even think about it.

I would say that for optimal performance, everything has to be in good working order - wiring, fuel delivery and ignition. The electronics need clean, reliable voltage.

It’s a little bit more of an investment up front but it’s best to get all the peripheral parts the system was designed to use like the in-tank pump, ignition box and distributor. It will save headaches later since you’re not trying to come up with workarounds when the disparate components don’t play nice with each other.
All very valid points when installing FI. At the time of install I added a PowerMaster alternator and upped the charge wire to 8 ga., added grounds.
 
My EFI problems sound very similar. I converted my 71 Cuda from carb to Edelbrock Gen 1 EFI with their version on the sump kit for the under-hood electric fuel pump. Late last fall the sump failed and I was towed home (tow of shame). The broken down cuda still sits in my garage. I'm torn between replacing the sump ($500) or going back to carb. When the efi works its great! But when their is a problem, a carb is easy to figure out and cheap to fix. Efi is not.
The thing is carbs rarely "break down"; they may run like crap but they'll limp you home. If the EFI quits you're left with a long list of troubleshooting tasks. At this point, the goal was to simplify my life.
 
There isn't a return line at the carb. The bottom port of the fuel regulator is a return line. If fuel perc becomes an issue as the weather warms up I may have to explore another return line
I am not familiar with the Fi-tech system, but I know the Sniper has a Flow and Return port at the TBI.....it might be worth checking if that is possible on the F--tech….I would say that is the biggest problem.

When I tried using the Regulator as a return path (dead-heading), the fuel flow was severely disrupted, and I had all sorts of problems. With a dedicated return line, those troubles vanished.
 
Let me take a slight detour to talk about EFI hose and fittings. For those of you contemplating EFI and going to an in-tank electric fuel pump, the fuel lines have to be upgraded, both in pressure rating and size. Most of our cars are running 5/16" OEM lines; EFI standard is 3/8" or -6 AN. The best approach is replace the OEM hardline with a 3/8" hardline with the correct flaring and use EFI fittings to connect to the rubber hose. I didn't go that route, instead I bought a kit from Tanks Inc. that included the LS-style filter/regulator, 25 ft of EFI hose, and various push lock fittings.
For those of you not familiar with push lock fittings - be warned! They are the biggest bear to seat in the hose. You can watch all the Youtube videos out there showing the different techniques - dip the hose ends in boiling water, heat with a heat gun, coat the inside of the hose and the fitting flares with axle grease, etc. etc. It doesn't matter what technique you use, assembling push lock fittings will ruin your life. It was the singular hardest and most taxing part of converting the fuel delivery system. For context, I'm a 250 lbs weightlifter that can practically hand-torque head bolts to factory spec and I was left curled up in a fetal position in a corner of the garage praying for Sweet Jesus to just take me. I eventually got it done but it scarred me for life.
So I was bound and determined to reuse the existing fuel lines. The only line I had to make was from the fuel filter to the regulator, and I was dreading the moment. But then my neighbor stopped by (same one mentioned earlier) and showed me the fittings FiTech sent him for his install. The company is Aeroflow, based in Australia and unfortunately they don't have a US distributor. It took 10 days for the fittings to arrive - not bad considering. However, I was able to seat the fittings in about 30 seconds. These fittings require an EFI rated hose clamp; the push lock don't require any clamping.
Here's three types of fittings: Left is the push lock (unknown brand), center is Earl's EFI rated and right is the Aeroflow.

IMG_5483.JPG
Although the Earl's has only one flare, its' still a bear to seat the hose. If you plan on using push lock, consider investing in this tool by Koul:
kts-409b_s.jpg

It's a little pricey at $279 on Summit but it will seat the fitting in a minute. Realistically it will take 20 minutes per fitting to seat a push lock without a tool, times the number of fittings and it becomes an entire afternoon job, assuming your fingers and hands don't give out first.
 
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I ran all SS braided Earls hose rated for EFI....and Earls fittings. The Aeroflow fittings are good also...but I used them them on other projects.

In this picture you can see how we started out - using the Regulator/Return bypass filter - that was replaced after about 5 miles of drive time....a real PITA. You can also see the Holley Billet Pump - another big FAIL - that Holley pump is crap, and so was the next one....so I opted for a German Bosch Pump, and have not had any problems since.
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Some pipe closer to the tank. I went for the external pump due to having a truck bed that I thought might come in handy one day... :D
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Christmas time...:lol:
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So Kiwigtx, I'm trying to piece together how you wound up; you eventually ran a Bosch pump but did you run the return line from the regulator or at the TB?
 
With the fuel delivery system finished at the tank, what remained was reattaching the Lokar linkage and providing juice to the fuel pump and choke.
The electrical was easy. Years ago I replaced the OEM distributor with a Pertronix unit which bypassed the ballast resistor. I just removed the FiTech harness from the ballast circuit and soldered in a connector for the choke and fuel pump.
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The linkage took a bit longer. Lokar came out with a nice FiTech specific bracket that wasn't compatible with the Edelbrock.
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But, taking a page from Greg Kern's best seller "How to Restore Your B Body Mopar on $10 a Day" I scrounged an earlier FiTech bracket that was laying around and it fit on the Edelbrock. Throttle cable and kickdown are in! IMG_5487.JPG
 
Thanks for the "shout out"....
 
The install was completed last weekend and since then I've driven the car twice. I don't want to drive it much yet because the original air filter won't fit, more on that later.
The engine fired right up. Using a tach and a vacuum gauge I dialed in the best lean idle. BTW, I'm running a Hughes Engines FT hydraulic cam with 232°/236° at 0.50 with .536 lift and pulling 16" vacuum at idle.
Took the car on a test drive with Maria riding shotgun. The low end and mid-range was phenomenal right from the start. Sorry guys, but the low end response blows away the FiTech. Now, I'm thinking it's just me wanting the Edelbrock to perform better after ditching the EFI. So after gassing up, I tossed the keys to Maria and had her drive home. As she peeled out of the gas station, her jaw dropped wide open and her eyes were big as saucers. She laid down rubber the next two stop signs! It was confirmed, the AVS2 is a serious carb.
After reaching operating temperature I put the carb through a series of stress tests. Started the engine at 5, 10, and 20 minute intervals with no issues. Granted, ambient temps were only about 65° so it remains to be seen how the Eddy will perform as outside temps start climbing. But we're off to a promising start.
 
Driving the car again this weekend gave more perspective. Idle is set at 850 rpm and with the fairly small duration and 110° LSA it idles real smooth. Off idle tip-in is incredible! One of the advantages of EFI is supposed to be the responsiveness , but I'm just sayin' the AVS2 feels better than the FiTech did. It could be the hardware, could be my tuning skills (or lack thereof), I don't know but I'm not looking back.
On the back roads out of Lincoln I opened it up and noticed there was still a plateau at WOT. I'm thinking it's the flat hood not allowing enough air. Even though it's an Eddy two plane manifold, it sits higher than the OEM. I had to run a drop base air filter on the FiTech, but it won't fit on the Eddy because of the choke housing.
IMG_5494 (1).JPG

But there's always a solution:
IMG_5488.JPG

Fiberglass six pack hood from Stinger/AAR arrived on Thursday. It's the reinforced model with bosses for hinges and the hood latch. The quality of this hood is A1. The top side is smooth as glass, it just needs to be scuffed, primed, and painted. Going with Organisol- replicated matte black.
 
No matter how well you have a carb tuned, if the weather changes it’s all out the window.

EFI is so much more precise than a carb. You can drill orifices and mess with jetting, air bleeds and emulsions until you’re blue in the face but in regular street driving with varied throttle positions EFI will do a better job of mixing the air and fuel because the “resolution” is finer. It’s like comparing an old, yellowed photograph to a high resolution image, not to mention having the ability to change or enhance the image further with software. All-out drag racing a carb might have the edge but that’s probably the only instance where that could be true. Even the best carb tuners are using sensors and related software to analyze their tune.

Regardless, depending on how robust the associated software is and how much you as a tuner know or learn, you can program it to whatever target you want. I’m an utter philistine when it comes to tuning but the few things I’ve done make me look like Austin Coil.

Also, Push-lok hose does not require the $279 tool. I use a heat gun on the hose and a small amount of assembly lube. Have to be quick about it and push the hose on before it cools but it works well.
 
So Kiwigtx, I'm trying to piece together how you wound up; you eventually ran a Bosch pump but did you run the return line from the regulator or at the TB?
I removed the regulator/bypass unit as pictured above after only about 5 miles of driving. Kept starving of fuel and shutting down.

The first Holley pump failed within 30 minutes of running.

The second Holley pump failed within 15 minutes of running.

Discovered that the 'alternate' plumbing of fuel lines in Sniper instructions was actually wrong, and should never have been put into print. This is when I removed the regulator/bypass unit. At that time I had been in discussion with JohnnyMac at BluePrint Engines also regarding the O2 sensor and a few other minor questions. This is when the extra dedicated Return line was installed.

After being told I would not get a refund from Summit from the first Holley pump due to length of time I had it (took nearly 3 months to ship it to me) I got pissed off and bought a Bosch pump from a local Speed Shop. Cheaper and works better. No issues now with the pump.

I want to stress quite clearly that regardless of a return line or not, the two Holley pumps were never going to work. It is a design flaw, and given that they are made in China, they are not to be trusted. After some initial trepidation, we decided to dissect the first pump to ascertain the problem.

Inside the pump is an impeller, which is 'driven' by the motor by means of a small plastic 'castellated' gear. This gear was NOT engaged fully onto the shaft of the motor upon disassembly. This is the reason the pump failed to pump.

The castellated gear could easily be snapped back to where it should be, but we were unwillingly to trust such a pitiful effort as far as design goes. Here is a video below showing the gear - unfortunately this was shot just after the gear had been pushed back into place....so it actually shows the pump working.



(apologies to @Kern Dog for video being shot in Portrait) :p

Since Holley apparently don't want to know about this issue, I am quite happy to share this video.

That's the last pump I buy from Holley....ever. :up:
 
All points well taken. In my case it came down to reliability vs drivability, although after a couple short sprints around town I don't feel I compromised there either. The Coronet and Dart are fair weather toys that never see rain or sub-freezing temps.
I will say that the AVS2 is much more responsive than the Thunder series Eddy on the Dart. I see a 650 cfm AVS2 in the Dart's future.
 
All points well taken. In my case it came down to reliability vs drivability, although after a couple short sprints around town I don't feel I compromised there either. The Coronet and Dart are fair weather toys that never see rain or sub-freezing temps.
I will say that the AVS2 is much more responsive than the Thunder series Eddy on the Dart. I see a 650 cfm AVS2 in the Dart's future.
I'm not getting at you at all.....but it does seem only fair to try and explore what may have gone wrong for you, and potentially offer some good advice to others reading this. :)
 
I've thought about an EFI unit for some time, and figured it was an eventuality (much like a Gear Vendors unit). In the meantime, I researched various carbs; sought advice from the clan here on FBBO; talked with local guys. After all that I plopped down the dough for a new AVS2 also. It just went on this week, so today is the day I'll fire it up.
I appreciate hearing of your experience with EFI. Maybe it's best to stay with the old-school carb setup. I went with the 650 version of the AVS2, and I suspect I'll be very happy with my choice.

@Hilljack68 What engine do you have?
 
I was considering EFI, but for me I don't get the same feeling when I see an old muscle car with EFI or a new Hemi. There's nothing better than opening a hood and seeing 3 2's or 2 4's sitting on top a big block. I'm not saying there is anything wrong with resto mods, they're just not the same. If I wanted a GenIII hemi, I'd buy a new Challenger.
 
Back in 2015 as I was getting nearer to completing the Coronet resto I decided to ditch the carb and go with EFI. The car was being built as a driver, something my wife could jump in and drive with no drama. That summer FiTech had taken SEMA by storm with their $995 throttle body EFI; ECM built into the TB so you didn't have to carve up the firewall running a bunch of wires. At the same time they released their Fuel Command Center or FCC; essentially a 1 quart fuel sump with a built-in electric fuel pump and regulator that was installed in the engine compartment. You kept the stock mechanical fuel pump and plumbed the low pressure fuel line into the FCC inlet, and the outlet pumped 58 psi to the TB. On paper it was a great idea; you keep your entire fuel delivery system stock in case you ever wanted to go back to carb (foreshadowing?).
I bought into the hype, ignoring my own rule about not being a guinea pig on new product releases. It was an easy install and when the car was finally roadworthy in early 2016 it fired right up. I ran the two wires for the handheld controller through the clutch pedal grommet in the firewall and hung the controller above the dash in the FiTech supplied stalk.
The unit never ran "right"; low idle like it wanted to die, surging at WOT. And it had a hot start issue related to heat soak. I could stop for gas and the car would start right up. But stop off for lunch or a quick beer at the local brewery and after 15 -20 minutes it wouldn't start. It would prime but nothing afterwards. I wound up carrying starter fluid in the trunk and I'd have to use it every time the car was stopped for 15+ minutes. I subscribed to a dozen EFI threads and forums, read hundreds of pages of posts, watched hours of Youtube, emailed and talked to FiTech tech countless times. I dialed in the IAC, fiddled with the Prime Mult and the Hot Start Crank.
I could prattle on forever about all issues but I'll condense the timeline to keep everyone from nodding off. In 2018 the fuel pump in the FCC died while entering the Mopars in the Park show in Rancho Cordova - had to be towed home. At that point I was ready to go back to a carb, but I had invested so much time and money into the system, plus everyone was saying it's the FCC. So the car sat for a few months while I collected all the parts from Tanks Inc. to convert to an intank pump. Got it running winter of 2018 but still couldn't solve the hot start issue.
Spring of 2019 the car was surging again and then one day it died coming to a stop sign. I was able to restart it again after about 30 seconds and went upon my way. Several days later it happened again. This time I turned around and headed home and the car died again for good as I was pulling into the garage. Long story short, FiTech took the unit back and shipped me a refurbed Gen II unit with the 4+2 harness (separating the power circuits) replacing the original 6 pin harness. To their credit, it was almost 4 years since purchase and they didn't charge me anything, not even shipping. That's either a) great customer service or, b) the felt obligated. Didn't matter, I figured I had a new and improved unit and could finally start enjoying my car. Well, the car ran fine but still couldn't solve the hot start heat soak issue. Then last year the handheld controller died. My neighbor across the street has the same FiTech unit in his pickup truck so I plugged it in and it lit up. I had a bad controller. To make matters worse, the original controller with a 2 bullet-plug input (which had sold on Summit for $100) was discontinued. Turns out over the last four years some FiTech engineer stumbled across the cutting-edge new fangled technology called a 'USB cable', converted their handheld controllers, and felt so proud of their new technology that they doubled the price to $200 (you know how pricey those USB cables can be).
At that point I was done. I had struggled for five years and in that time every major piece of hardware had failed at least once. I had to suck it up and come to grips with the wasted time and money, and the wasted moments of not enjoying driving my car for 4+ years.
Maybe next time have a professional install it.
 
Sorry to hear about all your frustrations. I think halfway through that I would have taken a sledge hammer to it and sent it back just to relieve myself!

Lot's of debate back and forth on the subject but nobody can deny the benefits of EFI, it is superior. What's sad is the companies that don't log thousands of miles on their products before releasing them to the public. On the other side of the spectrum you have the ones that claim they'll never go back to a carb.. maybe never tuned a carb correctly?? I don't know but I've had a few carbureted motors that didn't miss a lick and don't have the added concerns of finding specialty parts just common tools. This is what has kept me relying on my QF, no issues, no special parts, no break downs.

Good luck, hope the carb serves you well.
 
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