View Full Version : Going back to a carb
Toy4me
08-17-2020, 12:06 PM
While I hate to admit defeat I am convinced the EZ EFI 2.0 system is crap and their techs are totally useless. I have spent way to much time and money trying to get this to work. No matter what I do since day 1 it has always run rich and now it barely runs and fouls plugs quickly. I have run other FI systems with way better results. I wish I had never ventured this way but I did. I hate going backwards but I'm done. I have had the car for sale but can't sell it like this and maybe if I get it running correctly I'll keep it. It just has not been fun to drive for a while. I still have the carb that was on it and it ran fine. I'll just have to rewire a few things and replumb the fuel lines and regulators and such. I have not seen to many positive reviews about these systems and now I know why.
OK Rant over. Just have to vent a little.
I made the switch from the EZ EFI 2.0 to carb last fall. I had issues with the EZ. To make the switch straight forward I left the EFI in-tank fuel pump and retained the return fuel line. I used an Aeromotive EFI to carb conversion regulator (dual stage). Works great and now I have much improved drivability.
https://www.summitracing.com/parts/aei-13220
Olli
Toy4me
08-17-2020, 12:43 PM
Yes I will leave the electric pump in and use the return line back to the tank. Have to unlock the dist also. Not a big deal. Couple of other wiring issues but no big deal. Sounds like you are happy with the switch back to a carb.
rich grsc
08-17-2020, 12:50 PM
Yes the EZ 2 is junk, I fought it for a year. Fast finally admitted it was the issue, and I swapped in the Sportsman computer. The Sportsman is a direct plug n play with the EZ wiring harness. A completely different results, you can now tune and adjust the fuel setting, the car runs great. You could try talking them into a swap or at least a lower upgrade price
GoDadGo
08-17-2020, 04:34 PM
OK Rant over. Just have to vent a little.
Dude,
It's OKAY to rant and vent especially when things go awry.
We've all had setbacks and we power through them.
Hang In There & Keep Wrenching!
Steve
I had a similar experience with the FAST XFI Street. After fighting the same symptoms you describe, I swapped to the Holley Sniper and it's running great after some minor tweaks. I was also ready to go to a carb, but at my altitude I really wanted to make EFI work and I'm definitely in a good place with a very drivable car right now. The good news is that you have several options. The simplest is to work with FAST to get the better ECU that Rich described. If they won't work with you and you still want EFI to keep from having to rework your fuel system, the Sniper is a great option. If all else fails, you can go to a carb with some work, so don't give up on the car!
Dave
Toy4me
08-17-2020, 05:00 PM
Dave, That is another option I am seriously considering. Great reviews from people using the Sniper. I already have the fuel system and the dist locked out and my fans are run by the computer so it would be a pretty easy swap. The carb is the cheapest since I already have it but I do like FI. All my cars run FI and I pretty much tossed all my carb stuff so I'd rather stay that way. Considering all options.
D Stand
08-17-2020, 06:50 PM
I bought my mk4 in a pile of pieces. One of the pieces was a fast efi like you are dealing with. I found nothing good on the searches and have swapped out to the sniper including their hyper spark ignition setup. I haven’t had the first start yet but from what I have read it is a far superior product with better tech support. Don’t give up on the car just yet!
Dale
Norm B
08-19-2020, 11:30 AM
I bought my mk4 in a pile of pieces. One of the pieces was a fast efi like you are dealing with. I found nothing good on the searches and have swapped out to the sniper including their hyper spark ignition setup. I haven’t had the first start yet but from what I have read it is a far superior product with better tech support. Don’t give up on the car just yet!
Dale
I have the Sniper with the Hyperspark and it works good now. Had to shield the distributor and move some wiring to prevent RF issues that were causing the ECU to reboot on the fly. Tech support was very helpful while I was trouble shooting.
Norm
If you want EFI don't give up. Your setback is just another learning experience. Take some time to research different systems and you'll come up with a plan. If you can't make the old one work or sell it, you may be able to donate it to a local school that teaches automotive repair.
FFRSpec72
08-19-2020, 12:35 PM
I think you will be much happier !
D Stand
08-19-2020, 07:40 PM
Thanks Norm. Do you have pictures of your shielding? I did mount my cd box and coil on the firewall so the coil wire is running on the driver side past the sniper to the distributor, think I am asking for trouble?
Dale
I think a lot of the EMI related issues folks have with the Sniper come from either not de-pinning the unused wires from the harnesses or depinning, but not using the plugs that Holley recommends. If either of these two conditions apply, consider fixing them before looking at other possible issues. Holley sells a simple de-pinning kit.
https://www.holley.com/products/fuel_systems/fuel_injection/wiring_shop/wiring_tools/parts/567-101
Norm B
08-19-2020, 09:35 PM
Papa. I de-pinned all the wires I was not using and used the Holley supplied connectors. Re routed wires to avoid the ECU and still had problems. My oval Cobra air cleaner overhangs the distributor and may have been acting as a conduit for the RF. Holley tech support suggested wrapping the distributor with aluminum foil and that solved the issue. Made a shield out of some light aluminum sheeting to replace the aluminum foil and ran a ground wire from it to the frame. Covered it with Canadian duct tape (black hockey tape) until I got the cobra distributor cover off eBay.
Dale, my coil is on the driver side F panel and here are some pictures of the shield I made. Get the best plug wires you can and keep all wires away from the ECU.
Norm
Interesting. I have the same air cleaner and haven't had any interference issues. There are just so many variables with these builds.
Dave
Toy4me
08-20-2020, 07:48 AM
Decided to stay FI and ordered a Sniper. It should get here by this weekend.
DadofThree
08-20-2020, 08:41 AM
26,XXX miles with my Fitech. Keeps on Ticking.
Hope the Sniper works better for you.
Decided to stay FI and ordered a Sniper. It should get here by this weekend.
I really think you'll be happy with the Sniper. Just read through the entire Quick Start manual before you get started with the install and if you have any questions, there are lots of people on the forum that can help.
Dave
Joe Campbell
08-20-2020, 09:58 AM
That idea about shielding the distributor is a really good one. These throttle body EFI units with the ECU mounted seem to be very vulnerable to the noise in the engine bay. I had all the same challenges with the Fitech unit I have now. The other extremely sensitive area is in setting the IAC steps. Took forever to dial it in to Fitech's recommended range of 3-10. Found that as you get close to that range the adjustments you need to make get smaller and smaller or it way overshoots. Takes a little patience but it will run great after that. Even with that, the Fitech throws fits when I have it control timing, and never could get it fixed. Finally got it dialed in using the fuel only mode and it's acceptable.
All of that said, gonna still swap it out for the Pro Flo 4 port system over the winter, it's been truly plug and play in my Mustang.
Just to follow up on the electrical interference part of this discussion, here is what my ignition setup looks like with the large oval air cleaner:
https://thefactoryfiveforum.com/attachment.php?attachmentid=109715&d=1561735574
The only EFI wiring that runs anywhere near the ignition system are the coil wire and the CTS wires. All the other EFI wiring is on the back side of the engine away from the distributor, coil, and plug wires.
Norm B
08-20-2020, 10:58 AM
Papa, the only obvious difference between my setup and yours is, I am running the Hyperspark distributor. This has a 3 wire harness that runs back to the Sniper unit along the drivers side of the intake. I double shielded that and put it as far away from the ECU as possible with the sensor wires in a separate loom on top.
For anyone attempting a first start with both the Sniper and Hyperspark installed, follow the directions and set the ignition timing at a fixed value. Holley actually recommends that, if the engine had been running before with a different distributor, to leave that installed and run the car for awhile, then instal the Hyperspark. The Sniper throws a fit on initial start up when it is controlling both the fuel and timing. Let it get a basic fuel map established then enable timing control.
HTH
Norm
Papa, the only obvious difference between my setup and yours is, I am running the Hyperspark distributor. This has a 3 wire harness that runs back to the Sniper unit along the drivers side of the intake. I double shielded that and put it as far away from the ECU as possible with the sensor wires in a separate loom on top.
For anyone attempting a first start with both the Sniper and Hyperspark installed, follow the directions and set the ignition timing at a fixed value. Holley actually recommends that, if the engine had been running before with a different distributor, to leave that installed and run the car for awhile, then instal the Hyperspark. The Sniper throws a fit on initial start up when it is controlling both the fuel and timing. Let it get a basic fuel map established then enable timing control.
HTH
Norm
And with this post, you hit the magical post count ...
https://thefactoryfiveforum.com/attachment.php?attachmentid=133939&d=1597939866
D Stand
08-20-2020, 08:51 PM
133973133974133975OK you guys are scaring me with electrical noise and shielding issues. Please critique my install so far and let me know if I am going down the wrong path!
Thanks Dale
Norm B
08-21-2020, 11:05 AM
Dale, a couple of observations/recommendations.
1. If possible, I would get the coil wire out of the intake valley. You could run it along the driver side on top of your plug wires for a cleaner look while avoiding the ECU better.
2. If you look at the pictures in my post 14 and Daves' post 20, you can see that we have arranged the plug wires on the distributor to go straight out the sides avoiding the ECU as much as possible. You have a couple of wires very close to the ECU (the block on the front of the Sniper at the left edge of the red circle in the following picture). I would try to re-route those wires.
HTH
Norm
Donkeyteeth
08-21-2020, 02:38 PM
I fell your pain. I went from carb, to Holley Sniper, back to carb. I had EMI issues with the Cobra air cleaner, swapped for a round Edelbrock and it went away. Then I could not get the idle circuit to work so I removed the Sniper. Later found out my piss poor install of the intake manifold caused my gaskets to fail and probably caused the idle issues because the engine was compensating with a ton of fuel. Only good thing was I had the o2 sensor installed from the Sniper. I bought a cheap Air/Fuel gauge to help me tune the carb and now it runs so good I don't want swap everything back! Might go with a bypass fuel pressure regulator now since I still have the fuel return line. Good luck with which ever way you end up going!
Avalanche325
08-21-2020, 02:50 PM
I know a guy with a Backdraft that runs EFI and frequently does long trips. I don't remember what brand. He actually keeps a carb in his trunk for when his EFI breaks down. He has used it twice that I know of.
D Stand
08-21-2020, 10:19 PM
Thanks Norm. I will definitely shorten up the wires at the cap. Great idea with re-routing the coil wire too. I purposely did not route it with the plug wires thinking it could cause a miss fire on that side but your point is more valid with keeping it away from the ECU.
Dale
Cobradavid
08-22-2020, 09:05 PM
While I hate to admit defeat I am convinced the EZ EFI 2.0 system is crap and their techs are totally useless. I have spent way to much time and money trying to get this to work. No matter what I do since day 1 it has always run rich and now it barely runs and fouls plugs quickly. I have run other FI systems with way better results. I wish I had never ventured this way but I did. I hate going backwards but I'm done. I have had the car for sale but can't sell it like this and maybe if I get it running correctly I'll keep it. It just has not been fun to drive for a while. I still have the carb that was on it and it ran fine. I'll just have to rewire a few things and replumb the fuel lines and regulators and such. I have not seen to many positive reviews about these systems and now I know why.
OK Rant over. Just have to vent a little.
I have similar problems with the FiTech system on my daughter's 1966 Ranchero (rebuilt 302 roller block). It started out ok, but has gotten worse and worse lately. Now it runs super rich, is fouling plugs, and is very hard to start and keep running. It will not idle at all by itself. Once I do get it running and get it out of the garage, I need to air out the garage for 15-20 minutes just to get the noxious fumes out. FiTech has been minimally helpful.
I want to dump the EFI and go carb but will need to keep the in-tank fuel pump. Currently, the FiTech computer controls the fuel pump. What do I need to do to make the fuel pump work for a carb? Do I need a regulator and some sort of controller for the pump, or does the pump just stay on and the regulator returns unneeded fuel to the tank?
David
David,
Look at the second post of this thread, I posted a link to a dual stage pressure regulator. For electrical side of the fuel pump I used a fuel pump controller from Revolution Electronics. https://www.revolutionelectronics.com/Products/Fuel_Pump.html
Olli
GoDadGo
08-23-2020, 08:07 AM
Gentlemen,
If any of you end up going back to a Carburator, then you may want to look at Edelbrock's AVS-2.
I'm running the standard AVS-800 and may upgrade to the AVS-2 down the road.
They sport annular discharge primary jets and adjustable secondaries.
They come 500, 650 and 800 CFM versions.
https://youtu.be/3npwfIOdKPc
Steve
NOTE:...I'm happy with the Standard AVS, but feel the Annular Primary Jets will atomize the fuel better since I'm running a Race Style Single Plane intake.
Joe Campbell
08-23-2020, 10:28 AM
There are some regulators that will take the pressure down to carb levels. Other option is a spare in-tank fuel pump hangar with a carbed 85 Mustang GT pump in it. Don't need to use the return line with it in.
134145
If you want to go back to a carb and really want a challenge.
glastron351
08-24-2020, 10:04 AM
I just finished the conversion on my 408 from EFI to carb (Motor was in a 95 mustang utilizing an enormous intake and mustang computer, which I didn't want).
For a fuel pump I just went with a simple Carter electric fuel pump rated at 6-8psi I think...Summit/Jegs pretty easy to get....and yes it is noisy but once the car is started you cannot here it at all. Bought a single tube Fuel pick up from Breeze just to keep things simple.
Originally had a BLP 750 4150 carb on it (not cheap). Lots and lots of issues with this carb!.. No return calls or emails from BLP very disappointing!. On the dyno it kept going lean around 5k rpm.
Speed shop/Dyno owner recommended a Quick Fuel 'Brawler' 750 cfm carb and had it for me the next day. One jetting change on the secondaries (stock 84 down to 80) very nice AFR curve and picked up 25 rwhp over the BLP.
Currently at 411rwhp with an rpm cutoff at 5300 (faulty reve limiter...but thats another story).
While I would like to go to an EFI system at some point I wanted to get the car dialed in on a simple setup that takes out unknown electronic problems.
And as another comment the Dyno owner also recommended the Holly Sniper but in his words the Quick Fuel Carb will make the same power at about 1/2 the price and he pushes the EFI on the younger guys who don't know how to operate carbs :)
Just my 2 cents....its only money :D
Cobradavid
08-24-2020, 12:56 PM
Thanks, guys for the replies and advice!
After the hurricane(s)/tropical storm(s) get out of the area and I return from vacation, I'll be coming to the brain-trust for carb suggestions.
David
Chilly
09-01-2020, 04:07 PM
I have a 427 with carburetor looking for ideas for an in tank fuel pump setup any suggestion for a pump. Trying to stay away from the inline setup. (Not thrilled with the location blueprint suggests to mount the pump with IRS - behind passenger seat.)
FLPBFoot
09-01-2020, 06:23 PM
I have a 427 with carburetor looking for ideas for an in tank fuel pump setup any suggestion for a pump. Trying to stay away from the inline setup. (Not thrilled with the location blueprint suggests to mount the pump with IRS - behind passenger seat.)
Following: I have your same setup and the pump is on the passenger side down by the 4in main tube. It is noisy and I know their life can be an issue. I’d like an in tank once the external goes bad.
Steve
skidd
09-01-2020, 06:33 PM
In have no idea if it had the sustained flow for your 427, but this in tank pump makes 6psi dead headed at my 600cfm carb ony 302.
https://www.amazon.com/gp/aw/d/B008M4R69E
D Stand
09-01-2020, 06:57 PM
I bet breeze has the parts needed to install in the factory tank....
Chilly
09-02-2020, 09:06 AM
Thanks for the input. Gives me a direction.
Chilly
JETAV8R
09-02-2020, 09:56 AM
Gentlemen,
If any of you end up going back to a Carburator, then you may want to look at Edelbrock's AVS-2.
I'm running the standard AVS-800 and may upgrade to the AVS-2 down the road.
They sport annular discharge primary jets and adjustable secondaries.
They come 500, 650 and 800 CFM versions.
https://youtu.be/3npwfIOdKPc
Steve
NOTE:...I'm happy with the Standard AVS, but feel the Annular Primary Jets will atomize the fuel better since I'm running a Race Style Single Plane intake.
Steve,
I second the Edelbrock AVS-2. I have an AVS-2 500CFM on my 306. Runs great!. I started with a AVS-2 650CFM. A little rich for my little engine. Plugs ran black and fouled after about 500 miles. Switched to the 500CFM and seems be dialed in now, 4200 miles on the odometer. I have the 650CFM in the box if anyone is looking for one slightly used, with about 500 miles on it.
GoDadGo
09-02-2020, 10:05 AM
Steve,
I second the Edelbrock AVS-2. I have an AVS-2 500CFM on my 306. Runs great!. I started with a AVS-2 650CFM. A little rich for my little engine. Plugs ran black and fouled after about 500 miles. Switched to the 500CFM and seems be dialed in now, 4200 miles on the odometer. I have the 650CFM in the box if anyone is looking for one slightly used, with about 500 miles on it.
Does the AVS-2 650 sport smaller jets up front like standard AVS?
daberry
09-02-2020, 10:17 AM
Following
JETAV8R
09-02-2020, 10:18 AM
Does the AVS-2 650 sport smaller jets up front like standard AVS?
The AVS-2 650 has Primary .101 and Secondary .098
The AVS-2 500 has Primary .095 and Secondary .095
GoDadGo
09-02-2020, 11:25 AM
Jet,
Sorry, my mistake, I meant the bore sizes so I asked the wrong question.
I looked it up on their website and this is what I found.
500 / 1.44" & 1.6875"
650 / 1.44" & 1.75"
800 / 1.75" & 1.75"
I'm wondering if the 650 would over choke my 383 and make it nose over.
I'm thinking drivability would greatly improve since I'm running a Team-G Single Plane Intake.
Hummmmmm???????
Steve
Steve, I ran the numbers on your engine with the 800CFM carb and with a 650CFM. You’ll give up 8 HP & 5 lb ft of torque switching to the 650 CFM. However, you can loose much more than that by not tuning either carb correctly.
For those thinking of running a carb, by all means use one that you are familiar with and know how to tune. Tuning carbs is becoming a lost art and is so very important to achieve a good running engine performing to its potential. But if you are new to carbs, go with a Holley 4150 or one of the clones like Quick Fuel Technology makes (a Holley company) as they have been the most popular 4-barrel carb since 1957 and have the largest support of any other carb.
But don’t choose a carb because of first cost as in the long run a carb is not less expensive than the newer self-tuning EFI systems. To tune a carb correctly requires knowledge, skill, and support equipment that all ads to the cost. And if you don’t possess these, be advised that it’s becoming more difficult to find shops that have the experience to correctly tune carbs. If you were born after around 1970 you probably have very little if any experience with carbs.
Also, if switching from EFI to carb, pay close attention to not just the fuel pump & regulator required to support a carb but to the fuel line size. The lower fuel pressures run with carbs are much more sensitive to fuel line size than higher pressure EFI systems. Pressure drop from too small a fuel line will limit flow to the carb more than with EFI and you could end up starving the engine for fuel under high load/RPM conditions.
FLPBFoot
09-02-2020, 12:09 PM
I bet breeze has the parts needed to install in the factory tank....
I checked with Mark about a year ago and he did not have a solution.
Steve
GoDadGo
09-02-2020, 12:39 PM
Steve, I ran the numbers on your engine with the 800CFM carb and with a 650CFM. You’ll give up 8 HP & 5 lb ft of torque switching to the 650 CFM. However, you can loose much more than that by not tuning either carb correctly.
I'll play with it because the AVS is easy to deal with; however, the lure of going to annular boosters with smaller primary barrels may improve drivability.
You know the Mighty Mouse 383 engines very well and my combo with the tall port 215 Dart Iron Eagle Heads makes a ton of power.
I made over 460 HP @ 10-11 Degrees Initial Timing and am bumping 500 when we start the game at 13-14 degrees.
Questionable gas quality is why I keep the timing so low, plus it is easier to start too.
Just didn't know if going to a 650 would be an improvement or not.
skidd
09-02-2020, 09:34 PM
If annular boosters are important.. the summit branded carbs have them. They are copies of the old holly 4010 . A decent carb. I have one on my 302 (see sig for details). It runs pretty good IMO.