It's the early on that has frustrated most users. When you don't know what the problem is, how can you fix it. I had an ECU go bad in an EFI unit. How do you trouble shoot something like that. Had to send unit back to Mfr. to have it fixed. It only quit working when hot, ran ok when cold. Luckily the 2 times I got stuck with EFI, I was not too far from home so flatbed charge wasn't too bad.
EFI to replace Edelbrock carb
- Thread starter Rberger
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Me and people I know keep Edelbrock carbs on the shelf to use when starting a new build, because we know it work. Then we only change it out if we want more power. Never before heard anybody slamming an Edelbrock carb. I have a FiTech port system on my 408 and it starts easy and runs smooth. But, don't expect increased power or better gas mileage. The FiTech ported system is sort of like a do-it-yourself kit. If I do it again, I will use throttle body FI.
Another hit n run.
TheDuke
Member
My 383 runs like a dream on an Edelbrock AVS2 even when I lean on it. Whomever told you these carbs are trash doesn’t know how to work a carb and just wants to bill you for a 3-5k efi install. Watch a couple videos on YouTube from Muscle Car Solutions of Uncle Tony’s Garage and you will be a carb guru by the end of the weekend.
As far as the carb stumbling after a drive, I would suspect vapor lock is the issue. Get yourself a wood/plastic carb spacer to block the heat from seeping through the intake.
As far as the carb stumbling after a drive, I would suspect vapor lock is the issue. Get yourself a wood/plastic carb spacer to block the heat from seeping through the intake.
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goldduster318
Overzealous Car Modifier
You have to be really in it to win it to have long term good luck with EFI in a retrofit application.
1) Systems like FITech and the Sniper with the computer on the intake, electronics don't like much over 220F / 105 C for any periods, when it's over that the life drops pretty quickly. There are uprated electronics but I doubt they actually use them. It's not terribly hard for the top of your intake to hit 220F sitting in a parking lot with the hood closed. The ECU needs to be in the car ideally, or at least on the inner fender wells away from most of the heat -> even if that is the case, I would only do it with a stock one made for that installation.
2) You absolutely cannot run an external pump and especially an external pump with PWM/Returnless and expect long term reliability. An in-tank pump with feed and return is mandatory IMO. I would also NOT get caught up in the "Corvette fuel filter" installation. Put the regulator after the rails.
3) Using cheap parts. No no-name fuel pumps, regulators, or injectors
4) Bad wiring. no cheapo blue crimp connectors, you either crimp the ends on OE style or solder/heat shrink everything.
That being said it's been over 10 years on my Megasquirt 3 multiport system with coil near plug and not one issue. Car has an Aeromotive Phantom 340 fuel pump and a 3/8 feed and return line. I did Power Tour in June and averaged 19 mpg.
I'll also say a lot of "carb" problems are igntion timing related so get that dialed first. A lot of cars take a lot more timing at idle than you'd normally expect to be happy.
1) Systems like FITech and the Sniper with the computer on the intake, electronics don't like much over 220F / 105 C for any periods, when it's over that the life drops pretty quickly. There are uprated electronics but I doubt they actually use them. It's not terribly hard for the top of your intake to hit 220F sitting in a parking lot with the hood closed. The ECU needs to be in the car ideally, or at least on the inner fender wells away from most of the heat -> even if that is the case, I would only do it with a stock one made for that installation.
2) You absolutely cannot run an external pump and especially an external pump with PWM/Returnless and expect long term reliability. An in-tank pump with feed and return is mandatory IMO. I would also NOT get caught up in the "Corvette fuel filter" installation. Put the regulator after the rails.
3) Using cheap parts. No no-name fuel pumps, regulators, or injectors
4) Bad wiring. no cheapo blue crimp connectors, you either crimp the ends on OE style or solder/heat shrink everything.
That being said it's been over 10 years on my Megasquirt 3 multiport system with coil near plug and not one issue. Car has an Aeromotive Phantom 340 fuel pump and a 3/8 feed and return line. I did Power Tour in June and averaged 19 mpg.
I'll also say a lot of "carb" problems are igntion timing related so get that dialed first. A lot of cars take a lot more timing at idle than you'd normally expect to be happy.
With all the EFI people trying to shove this down our intake, you would think that they would iron out the problems the average guy is having. Why don't they start a forum where people can post their problems and have a Tech respond. Now if you need Tech support spend hours on the phone listening to music and accomplishing nothing.
All of this is really great advice, but the part about not using the Corvette filter and return system...while I've always agreed with that, can you tell us what your reasons are? Thanks.
I ran the older Edelbrock Performer Carburetor #1406 for a while and have had no issues with it driving around town. The only time i had issues with it was because the car was sitting for a few years and I just opened it up and cleaned the old fuel residue.
Some of the issues I heard about EFI was due to them having the ECU built into the throttle body and suffering from over heating issues. It might be safer to go with an EFI that doesn't have the ECU built into the throttle body.
goldduster318
Overzealous Car Modifier
Well the Corvette filter does 2 things. 1st, it makes the line only a feed to the front of the car (anywhere in front), if you have an aftermarket pump without a check valve or the car sits for a while you have to crank to purge the air. That's a minor problem.
2nd, what it actually is, is a regular fuel filter, set to 62 psi with a return there. Do you want to run 62 psi at idle with larger injectors in a performance application? Will it actually bypass enough fuel with a big fuel pump? You also get hydraulic delay due to the distance and the dead heading past the filter. With a big pump the 5/16 return may also be too small.
If you have a return system you have neither of these problems, it can vacuum reference to the intake to drop the fuel pressure at idle, and it actually regulates the fuel to what you want for consistency. I'm only running fuel pressure in the mid 40s wound up and about 40 at idle. Also with it after the rails the fuel is always there and it responds to the pressure drop after feeding the injectors.
How precision do you think both the control of the actual fuel pressure and the quality control of that filter is? It may make you chase your tail, or do you run a couple more feet of fuel line and use a real regulator? Would be even worse if you were running boost.
In our cars you're doing a fuel system anyway. Why not just do a little extra to never worry about it again?
Thanks! I've argued for years that those filters weren't good enough for a true HP application. They were arguably good enough for stock Chevys. I was aware about the 62PSI regulation, but hadn't taken all the rest into account. Makes perfect sense. Thanks!
"upgrading" to EFI is opening a totally different and WAY WAY more expensive can of worms. Did it once on a 318 and will never ever do it again. Have Edelbrocks on all my cars after that. Put a bung in the exhaust pipe for an O2 sensor and buy an Air Fuel Ratio meter setup. Way cheaper than EFI. What ever the cost of the EFI system is the fuel system will be at least the same cost to double what Sniper's or FiTech's are. The Edelbrocks are TRIVIAL to change metering rods and main jets.
340sFastback
Well-Known Member
Sounds like some real idiots giving advice at that shop. Which is pretty common these days.
What Edelbrock carb you have? Maybe its old tired internal passages blocked?
I ran an Edelbrock AVS2 650 when my stock 340 was in there. Had to jet up, bigger accelerator pump nozzles, ect but once tuned it was an outstanding carb.
What Edelbrock carb you have? Maybe its old tired internal passages blocked?
I ran an Edelbrock AVS2 650 when my stock 340 was in there. Had to jet up, bigger accelerator pump nozzles, ect but once tuned it was an outstanding carb.
DionR
Well-Known Member
My brother and I used a returnless system on his 6.4 swapped Demon with a Corvette filter. We even went to GM for the filter as I had heard of problems with the aftermarket ones.
His motor has a cam and aftermarket intake and MMX suggested a big in tank pump. When we energized the system the pressure gauge showed like 100psi and would hold that pressure for days. He called someone (can’t remember who) and they said those Corvette filters won’t work with a big pump as they just can’t handle the flow, so we added a filter and regulator but kept the returnless system.
We used a returnless system as that’s what the stock PCM expects. I think the factories use that system because it is cheaper as it saves a fuel line run. And I think even high HP cars like the Demon 170 was still a returnless system, and if so I would say it can be made to work. I’m not saying the stock PCM couldn’t work with a return system, but why spend money on more fuel line if it works?
My build will have a returnless system as well, but using a Gen5 Camaro pump in the tank. Simple to plump and good enough for me.
To be clear, not arguing that a return style system isn’t better, only that it isn’t absolutely necessary.
His motor has a cam and aftermarket intake and MMX suggested a big in tank pump. When we energized the system the pressure gauge showed like 100psi and would hold that pressure for days. He called someone (can’t remember who) and they said those Corvette filters won’t work with a big pump as they just can’t handle the flow, so we added a filter and regulator but kept the returnless system.
We used a returnless system as that’s what the stock PCM expects. I think the factories use that system because it is cheaper as it saves a fuel line run. And I think even high HP cars like the Demon 170 was still a returnless system, and if so I would say it can be made to work. I’m not saying the stock PCM couldn’t work with a return system, but why spend money on more fuel line if it works?
My build will have a returnless system as well, but using a Gen5 Camaro pump in the tank. Simple to plump and good enough for me.
To be clear, not arguing that a return style system isn’t better, only that it isn’t absolutely necessary.
matthon
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FiTech dual quad here.
FiTech has been extremely helpful, and the times I needed to call it was no problem calling and getting an actual person on the phone.
Tbs require a constant 58psi.
The ecu controls the pump with pwm (pulse width modulation), basically slows pump at idle, ensures pressure throughout driving conditions.
Based on that, I went with the corvette filter/regulator.
Each tb has a regulator, if you want to go that route.
They sent an in tank pump with a regulator as well.
There are plugs for the tb and pump regulators, which I installed.
I also ran a harness and a relay for a future regulator, if needed/wanted.
Turn key to run, pump primes the tbs, tbs squirt a bit of fuel, as intended, starts immediately every time.
One exception, it's butt cold out, I'll turn to run twice to get an extra squirt.
I ran it with carbs on the tunnel ram for a few years, would not start immediately, every time.
I expected, heck, I prepared for an external regulator, however it has worked as designed.
No issues with fuel psi, and it's a different animal with the tbs.
Tunnel ram keeps ecu away from underwood heat.
Just reporting the facts/results from my experience.
Efi is definitely not for everyone, not needed for many, and more importantly, it's not a simple bolt on swap and go.
Wiring, power, grounds, fuel, everything has to be considered and redone.
We did Power Tour as well, 2,500 miles round-trip, quick math, based on a $4/gallon average, we got 23mpg.
We actually met another guy running a bb chebby dual quad tunnel ram FiTech on the tour.
FiTech has been extremely helpful, and the times I needed to call it was no problem calling and getting an actual person on the phone.
Tbs require a constant 58psi.
The ecu controls the pump with pwm (pulse width modulation), basically slows pump at idle, ensures pressure throughout driving conditions.
Based on that, I went with the corvette filter/regulator.
Each tb has a regulator, if you want to go that route.
They sent an in tank pump with a regulator as well.
There are plugs for the tb and pump regulators, which I installed.
I also ran a harness and a relay for a future regulator, if needed/wanted.
Turn key to run, pump primes the tbs, tbs squirt a bit of fuel, as intended, starts immediately every time.
One exception, it's butt cold out, I'll turn to run twice to get an extra squirt.
I ran it with carbs on the tunnel ram for a few years, would not start immediately, every time.
I expected, heck, I prepared for an external regulator, however it has worked as designed.
No issues with fuel psi, and it's a different animal with the tbs.
Tunnel ram keeps ecu away from underwood heat.
Just reporting the facts/results from my experience.
Efi is definitely not for everyone, not needed for many, and more importantly, it's not a simple bolt on swap and go.
Wiring, power, grounds, fuel, everything has to be considered and redone.
We did Power Tour as well, 2,500 miles round-trip, quick math, based on a $4/gallon average, we got 23mpg.
We actually met another guy running a bb chebby dual quad tunnel ram FiTech on the tour.
goldduster318
Overzealous Car Modifier
Anything with PWM will have a fuel pressure sensor that the computer needs to control the fuel pressure. Otherwise, pressure drop from any variable (big change in engine load, fuel filter restriction increase, etc) would result in it leaning out. You'll find that OEM cars that have a PWM/return less have a sensor and usually no fuel filter other than the sock in the tank. Most of the time in these you see the sensor near the tank even. If the sensor has a fuel filter after it it's a virtual guarantee you'll have problems over a long enough span.
Cheaper is the reason you do returnless in a factory application. As mentioned, you can have problems with mixing parts, especially performance type pumps and OE parts not designed for it. Not entirely sure all the fuel pumps are necessarily made for PWM either.
Just much harder to make a mistake with a return system.
Cheaper is the reason you do returnless in a factory application. As mentioned, you can have problems with mixing parts, especially performance type pumps and OE parts not designed for it. Not entirely sure all the fuel pumps are necessarily made for PWM either.
Just much harder to make a mistake with a return system.
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Sometimes you see PWM combined with a return and regulator, usually when running a very large fuel pump on the street. The idea is to throttle down the pump at low RPM to reduce heat buildup.
rmchrgr
Skate And Destroy
EFI is not magic. These systems employ the exact same tuning parameters that a car with a carburetor does but it's presented in a digital/software-based program. Period.
It's definitely not for everyone though especially people who think it's being "shoved down their throats". That is total nonsense - no one is pointing a gun at your head forcing you to shitcan your trusty old wheezer. Carburetors have their place and for those who doesn't tinker much and/or only putt their car to cruise nights or local car shows EFI is not worth the money or effort.
I know this might be an unpopular opinion but the reason the "average guy" has "problems" with EFI conversions is that "the average guy" thinks they know more than they do. If the "average guy" knew better, no one would be running a carburetor any more. Go to the drags these days, all the fastest cars are equipped with some sort of ECU and are tuned with software. Sure there's still fast carburetors out there but don't be mistaken, they're using software aids too.
To the O.P. - is EFI what YOU want or does someone want you to pay them a couple grand to make that decision for you? if you're relying on someone else to diagnose and fix your issues, you really have no business considering EFI. Have whatever place you chose solve the issues at hand first and go from there. My guess is they can't or won't because they don't have experience properly diagnosing and repairing a poorly running car with a carburetor, no matter the make or type - those guys are gone. Even if someone's had a repair shop going for 30 years they've never dealt with carburetors on a daily basis. There's no check engine light on a '70 Dart.
In reality, retrofit fuel injection systems are expensive, time consuming to install and require patience to work through bugs. I always suggest completely re-wiring the car while upgrading to modern wiring and fuse boxes to avoid static interference. You up for that? How about an entirely new in-tank fuel delivery setup and a digital ignition system? No? Keep your money in your pocket then because you can't half-*** EFI or you will be worse off than you were.
And let's be perfectly clear - EFI won't "fix" your issues, it will only magnify them. Make sure the car runs as well as it can first before even thinking about converting. Rebuild the carb or just get a new one. Make sure there are no intake or exhaust leaks, ensure your timing is right under all conditions and loads etc. This is basic stuff that anyone can do. Again, EFI will not fix a miss or intake leak.
I've experienced the EFI shuffle directly when a neighbor asked me to help him convert his Brand X cruiser. He was having drivavbility issues because everything on the car was trashed and he couldn't get it to run right. He saw me driving my Coronet around with a Sniper and wanted it for himself. After going over a plan with him, he essentially ignored everything I suggested and did the install himself. He had no clue how to wire a car and made a mess. He ended up having a terrible time with it and almost ripped it all out in frustration. I said sorry man, not sure what to tell you. I don't have time to babysit grown men. It's been years now and he still can't figure it out. Guys are stubborn, lazy, won't read instructions, don't know anything about wiring or electronics and often buy into the advertising claims that you don't have a lift a finger and the car will magically run better. Horesshit.
If you're wary of spending a bunch of money, don't have wiring skills, don't like or trust "computers" and don't want to put any effort into the tuning, save your money and stay with a carburetor.
Sounds like you really have it nailed down. I applaud you. It appears that if you go EFI, regardless of what style, the key is not to cut corners. ANY corners.
rmchrgr
Skate And Destroy
Lordy! Just the sheer amount of posts there would make me say no to EFI. That is, IF I was considering it, which I'm not. lol
DionR
Well-Known Member
Personally, PWM fuel pump control makes a lot of sense, big pump or not. Why have the pump thumping away at full speed all the time and bypassing a bunch of fuel that isn't needed? And with PWM there is no need for a regulator at all, just a sensor. Not that it is cheaper, the controller kits are fairly expensive.
rmchrgr
Skate And Destroy
It's no different than this forum. There's thousands of pages of repetitive questions about basic stuff.
Like I said, it's not for everyone. If it's intimidating/confusing or whatever then just stay with what you know. No need to add complexity.
That's where people get me wrong with it. I spent YEARS on the line as an alignment tech. Why is that important? Because in dealerships, the alignment tech gets all the stuff no one wants or can figure out. Which means I got a ton of driveability. I learned a lot. I know way more about EFI than I let on. I know enoufh to know I don't like it and that's enough for me. Intimidated? Hardly. I detest it. Computer and cars should have never happened.
rmchrgr
Skate And Destroy
I doubt the O.P. cares about pulse width modulated fuel pumps.
My EFI Holley in-tank pump uses a preset filter/regulator installed just forward of the tank. it has a return port so no need to run a return the length of the car. The Sniper throttle bodies are internally regulated but do require a return unless you use the one I have.
DionR
Well-Known Member
No argument. The thread kind of went off the tracks into the plusses and minuses and who like what and why. It was just a general comment, but I agree it probably isn't helpful to the OP.
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