HELP me decide... EFI or carb!

So I am working on this retired Gen 4 Cup car project. I have been lucky enough to get a couple of 2016 "eagle" Gen 3, 5.7 Hemi engines. Both need to be gone through, so I am using both to build a test mule motor. I am looking at two options. Option one.. .go with a carb intake and whatever fuel feeder I come up with. Use a Hemi 6 controller from MSD and go on. Second option is the stock EFI (stock -ish). Since  I have to swap out the reluctor wheel in any case to work with the MSD, I could also swap it and run the 2005 Dodge PCM which is easily tuned and modified. Of course, I will have to learn to tune the thing or pay someone to wrote the tune for the cam I'll be running. Cost is $700 ish different. Money isn't the deciding factor totally so let me hear your opinions! 

Carb setup roughly $2300 all in. 

Fuel injection $1650 including buying the set up for HP tuners, new injectors, and new throttle body. 

Total:$1,632Total:$2,335




 

What's the intended final use? To go with two extremes, if it's a turbo drag car there would be no way I'd convert a factory EFI motor to carbs. On the other end, a carbed (or better yet, dual quad) intake would look a lot better than the factory intake on a T-bucket. (Unless the T-bucket was also a turbo drag car, in which case, back to EFI.)

MadScientistMatt said:

What's the intended final use? To go with two extremes, if it's a turbo drag car there would be no way I'd convert a factory EFI motor to carbs. On the other end, a carbed (or better yet, dual quad) intake would look a lot better than the factory intake on a T-bucket. (Unless the T-bucket was also a turbo drag car, in which case, back to EFI.)

Strictly a track day car and flying mile competitor. No turbos on this one. 

The reality of DIY EFI is that you end up with a new hobby more so than a fueling system. Lots to learn, lots of guessing and possible $$$ spending opportunities.

The carb amd MSD box gives you coarser control of the engine,  but easier to wrap your head around.

Either way, the fist step I would do is install a wide-band O2 sensor.

NOHOME said:

The reality of DIY EFI is that you end up with a new hobby more so than a fueling system. Lots to learn, lots of guessing and possible $$$ spending opportunities.

The carb amd MSD box gives you coarser control of the engine,  but easier to wrap your head around.

Either way, the fist step I would do is install a wide-band O2 sensor.

What if you didn't already know carbs?

Factory Efi?  Yes.  Aftermarket? No. 
 

don't forget fuel tank and plumbing differences!

I wish we had left our 72 bronco carb'd.  it was running great.  Then I Efi'd it.  It's finally good but I wouldn't say better than the carb.   But it's aftermarket.  Factory systems just work.  

I have gone with Factory EFI in a few swaps and would do it again in a heartbeat. I would not go aftermarket EFI however. I'm currently helping my buddy Roy go Factory late model Hemi EFI in his 68 Cuda. He had the same conversation with me about carb and MSD versus Factory EFI, and drivability and reliability wins out with EFI every time. At least that's my opinion and worth every penny of what you paid for it

Cose to stock motor and track toy? Factory EFI would be my choice, particularly if you're not an experienced carb tuner.

Aftermarket EFI is not as bad as some say.  I did it 15 years ago when systems were much cruder and got a decent set of tunes in a few tries.  Now many are self learning, or so they say.  

Since you're working with engines that basically came with EFI, I'd stick with a tuneable, factory-style EFI setup, especially if it's multiport. 

Aftermarket EFI is usually as good as whoever's installing and tuning it. I converted both the old LA 318 and the current Magnum 360 in my Power Wagon to MSD Atomic 2, and it works pretty well. Only real issues I've had with it are caused by either the aftermarket throttle cable/kickdown setup (not supplied by MSD/Holley) or the tune itself. A lot of the issues I see on the install side are due to people not following the install instructions and wiring/plumbing things incorrectly. 

In reply to MadScientistMatt :

I can tune carbs. Probably one of the few left that "Ain't skeered" of things like the Q Jet and Thermoquad. 

In reply to wvumtnbkr :

If you cant figure out carbs then you are not going to like learning EFI.  Or maybe you will, who knows?

Carbs are like trying to get 4 of your buds to an event at the  pub at  the same time. EFI is getting 20 of them to show up, they all have to show up in the proper order,  in the proper parking spot and they  first have to check with their moms and their wives. Glorious when it works.

If you are building anything with headers, let me ask you: When was the last time you saw a header that did NOT leak? It is a game killer for EFI because it messes up your O2 sensor data and all of your friends show up like they all pre-drank and got bad  vibes from the family. The carb will see the same lie but since it does nothing  in response to the info, just keep driving.

NOHOME said:

In reply to wvumtnbkr :

If you cant figure out carbs then you are not going to like learning EFI.  Or maybe you will, who knows?

Carbs are like trying to get 4 of your buds to an event at the  pub at  the same time. EFI is getting 20 of them to show up, they all have to show up in the proper order,  in the proper parking spot and they  first have to check with their moms and their wives. Glorious when it works.

If you are building anything with headers, let me ask you: When was the last time you saw a header that did NOT leak? It is a game killer for EFI because it messes up your O2 sensor data and all of your friends show up like they all pre-drank and got bad  vibes from the family. The carb will see the same lie but since it does nothing  in response to the info, just keep driving.

I like that analogy!

I never had experience with carbs.  Only EFI.

When I started road racing a 78 Malibu, it had a carb on it.  I bought a wide band o2 sensor and a tuning kit and started tuning it like it was efi!  Pretty simple!

However, I did eventually put a tbi system on it.  I got tired of fiddling with floats and transient things that made it difficult to be smooth.  I probably lost some powah! But more than made up for it in driveability!

Me personally...  I'd be adapting a stock efi system.

In reply to NOHOME :

Wow, thanks for the explanation, had not thought about it like this, and definitely helps to explain the issues I had with my Fitech unit. Yes, had headers, yes they leaked and yes the EFI computer ran rich and had issues all explained by what you just said. My favorite is the "carb sees the same lie, but does nothing and keeps driving" :-)

It's funny; I prefer EFI to carbs, but I have both in the fleet. A lot of the tuning principles I learned with carbs apply to EFI (especially DIY EFI like I have on my truck). The biggest difference is turning a wrench vs. uploading a tune to the ECU. With my truck, I can monitor everything that's going on in real-time and make changes with a few clicks of a button. On my carbed Trans Am, it's more of a guessing game trying to figure out what the thing wants, but almost more rewarding when you get it right. Makes me feel like a sorcerer when I get that thing running as it should. 

NOHOME said:

The reality of DIY EFI is that you end up with a new hobby more so than a fueling system. Lots to learn, lots of guessing and possible $$$ spending opportunities.

The carb amd MSD box gives you coarser control of the engine,  but easier to wrap your head around.

Either way, the fist step I would do is install a wide-band O2 sensor.

You nailed it there I suppose. I am one of those "perpetual learners". I WANT to learn how to tune the EFI. I worked for Dodge when the first TBI system came out on the 318. There was NOTHING you could do to it and it was so fickle. I plan on using the stock system and not some other standalone. 

I do plan on adapting the stock EFI. The motor is a 2016, but the controller I will be using is the 2005-2008. There are no security issues tuning them and no Security Interlock to deal with. My "roadblock" is learning HP tuners and all of the tables. I can do a carb all day, but I like being different. 

In reply to NOHOME :

Best analogy EVER!

There had been a few MFI systems around when I started wrenchin', but financially unaffordable to my crowd. EFI was coming out, but not on the stuff we cared about. 
So far, I've never hopped up any of them new-fangled EFI, but have learned a fair bit about simple maintenance. 

Looks like factory EFI has won the battle!