Team Chevelle banner

EFI vs carb

  • carb

    Votes: 38 44.7%
  • EFI

    Votes: 47 55.3%
1 - 20 of 49 Posts

· Registered
Joined
·
157 Posts
Discussion Starter · #1 ·
72 chevelle 454
ive been looking at getting a holley 750 cfm carb or a edel 800cfm thunder carb, then i got side tracked looking at edels EFI systems. what are your guys opinions on the efi conversion systems? anyboy running them? and do you think they are worth the $3000?
 

· Registered
Joined
·
5,677 Posts
break out the december 1991 carcraft.
giant efi test...Although i did not like the choice of internals on the test engine , it does give some comparatives...

I love my carb, or carbs....I have brefiely thought about efi , and seen results of a TBI to MPFI swap that left the owner mechanic scratching his head as to , why isn't there any more power....Stock stuff just aint good enough.

You could make either of your choices work great with enough time and knowledge...

If hood clearance isn't a problem i would choose 2x4's on a tall tunnel-ram..Like 11or 12" tall...lots of atomization time...and decent mileage if set up right
 

· Registered
Joined
·
655 Posts
I'd rather buy 2 carbs and a wide band -- then play with them and still be not halfway to the price of EFI.

Now if you are after the ultimate in driveability for year round driving and varying altitudes then OK . . . EFI may be your best bet. But I can get a carb pretty darn close.
 

· Registered
Joined
·
81 Posts
If youre a do it yourselfer, now days it is possible to get into a decent efi system for a similar price to carbs.

'730 computer and harness = 100 bucks (wrecking yard)
single plane intake with injector bungs 199-250 (only slightly more expensive than carb types)
chip burner = 120 bucks or so (willem programmer is less than a hundred)
fuel rail stock = around 12 bucks a foot
fuel pump (or pumps) same price as carb type electrics (or F250 external inline pump from wrecking yard)
Tunerpro RT software = free!!
ALDL cable = 15-70 bucks (15=diy serial cable ,70 = moates USB cable)
fuel pressure regulator = same cost as carb versions
injectors = 20-300 bucks depending on source
Throttlebody = gutted holley carb


All in all it cost about the same as a carb setup if you can handle rolling your own system. A GM computer running modified $8D code is as good as all but the most extreme aftermarket computers.

If you have ANY interest in EFI go to thirdgen.org and read up in the "DIY PROM" forum, best EFI resource on the web.
 

· Registered
Joined
·
62 Posts
Half an hour ago, i wrote a real long and informative post on the advantages and costs of EFI, prices, parts and links to jobbers, until i accidentaly slipped on the computer and somehow got alt+F4 in at the same time and my masterpiece got annihilated. Now im kinda pissed of but i'll try to make a short summary.

Im going with EFI for the new beast.

It'll cost about 2500$ with
Sensors
Ignition box
EFI (ecu) box
Harnesses
8x 1680cc bosch or Ford racing injectors

The initial mapping and final tuning is about a day in the dyno (or in car) preferrably with the guy who supplied the EFI for you,

Thats pretty much everything needed, and this is a "real" EFI, not edys/holleys TBI style stuff.

The other stuff you need is a fuel pump, some plumbing, throttle pos sensor and maybe a pressure regulator, talk with the guy supplying the rest of your EFI !


Now compare that to the two 1000$ King deamon's that i'd been up for. This is also a DIS ignition
 

· Registered
Joined
·
344 Posts
In a race car its a must... The carb guys that are fast always use a "computer" and a bunch of "ignition boxes"..

Hey, threw the carb away and add injectors. Everything is already there but many folks dont use it.

And when you compare EFI with carbs, dont forget carb type ignition, boxes and boxes, external broadband lamdas, computers for logging, sensors for activating fans, pumps, lots of gauges.

A good ECU and a Dash will do the job, cheapar, faster, better and alot easier.
 

· Premium Member
Joined
·
2,574 Posts
I prefer a carb because its taken me the last 7 years to figure out how to make a carb work half decent.
Guy
 

· Registered
Joined
·
1,350 Posts
find a used carb, spend the rest on a od trans. Holley's are really simple to rebuild. A well tuned carb is pretty close to a efi. My car starts without stepping on the gas as I crank the engine, and can drive it away instantly without missing a beat. But of course I'm sure in weather below 50F it will be another story.
 

· Registered
Joined
·
1,794 Posts
This controversy has been beat to death, and it is still a controversy. Casual logic and F1 would lead us to believe that FI should be superior. Darin Morgan and a lot of other top tuners still say carbs have the potential to make more power.

What we do know is fuel distribution will be better with FI over a wider range than carbs simply because FI can have better manifold designs, maybe. Carbs allow better fuel atomization and that gives them a cooling advantage that FI does not have, leading to denser mixtures than FI is capable of.

To my way of thinking, the ultimate would be 8 piezo nozzles in an IR type manifold. Like the injectors on throttle body injectors, but one for each cylinder. That would give good mixture cooling and atomization along with even distribution. I have no idea if something like this is already being produced. I don't get around much.

I wish John Bathe were still alive. John was somewhat of a fuel management specialist from St Louis, MO. John designed the FI nozzles used on 5 valve Ferraris, and, as I understand it, was responsible for some of the changes done to the AFB carbs after they were bought up by Edelbrock. (John did not work for Eddy. Someone correct me on this if I'm wrong.) John won his class at Indy in the late 60's or early 70's with a BB fuel rail, and he was quite a character besides being an excellent tuner. Here is a short link that mentions John: http://fromtheboonies.livejournal.com/

I used to be able to discuss stuff like this with John, and had great admiration for his knowledge and ability to drive anything like an absolute crazy person. My favorite motorcycle picture is a short tracker with his feet on the pegs, sliding sideways, doing a wheelie, and looking backwards at his competition. John Bathe was that kind of a guy.
 

· Registered
Joined
·
81 Posts
One thing to keep in mind is that carbs have been around for over 100 years and have more or less been perfected. EFI has been around for just a little while and is rapidly getting better by the day. Early aftermarket and OEM EFI systems sucked big time! Even current EFI systems vary greatly in capability.
 

· Registered
Joined
·
130 Posts
One thing to keep in mind is that carbs have been around for over 100 years and have more or less been perfected. EFI has been around for just a little while and is rapidly getting better by the day. Early aftermarket and OEM EFI systems sucked big time! Even current EFI systems vary greatly in capability.
Fuel injection was patented in 1896 and commonly used in diesel engines as early as the 20's. Many gasoline fighter planes used it in WW2. First electronic FI was probably DeSoto in '58 (made by Bendix). So that makes EFI 50 years old.

But yeas, EFI in the 70's and 80's were not that great.
 

· Registered
Joined
·
1,794 Posts
Also, all the car companies need to stop burning gas at 14.7:1, to meet polution standards, and start running Wide Band sensors for milage. We MAY be getting clean air, and I doubt that is really happening, because my carburated 86 Dodge van has lower emmissions than my new 2006 Dodge van. And the old one gets the same mileage as the new one. DUH!

If you double or tripple the mileage, you cut the green house gasses. What we are doing now is burning more gas to make more CO2. We could be burning less gas to make less CO2.

Here is what I know to be fact. A 58 Ford 6 cylinder got 22 MPG on the highway. It had a log type manifold, which is as bad as a manifold can get for even fuel distribution. The tail pipes on those cars burned white, denoting very lean mixtures.

My 6 cylinder 2006 van gets 22 MPG on the highway. It has a high zoot manifold with FI and twin Lambda sonsors. The tail pipe on my van is almost black, indicating, to me, that it could be running a lot leaner.

All newer cars have tail pipes that look like they are running rich. I think that is because they are all running at 14.7:1, instead of 17:1 or 18:1, like the old carburated cars did.

I'm all for clean air, but it is a farce. All we are doing is Federally mandating rich burning cars. Who benefits from that? There has been virtually zero progress in mileage in the past fifty years, except in a few instances. What is interesting is Corvette turned in fantastic mileage numbers with the old mechanical injectors, and they are also turning in great numbers today with their electronic FI. Evidently, the people at GM know something that the people at Chrysler don't.

The Chrysler's with the 4 valve 3.5's (Concords and Intrepids) got close to 30 MPG, but no one bought them. Go figure.
 

· Registered
Joined
·
130 Posts
Running leaner than 14.7:1 drastically increases combustion temperature which forms NO and NO2. NOx (not to be confused with nitrous oxide which is N2O) causes acid rain and algae blooming.

NOx has been the problem with "clean diesels" but is supposed to be controlled now with NOx traps (urea, ammonia etc). I wonder if you could run a gasoline engine lean for economy and use a diesel NOx trap?
 

· Registered
Joined
·
87 Posts
... The Chrysler's with the 4 valve 3.5's (Concords and Intrepids) got close to 30 MPG, but no one bought them. Go figure.
Because they we're crappy cars that broke down easily...


I think both systems have their place. For me the idea of FI is great, but the price over benifit (cold starts, tunability, ect.) isn't worth it to me... If I had the money I'd do it, but I'd rather dump the 3k on a tremec with a .64 final gear... or something along those lines.
 

· Registered
Joined
·
655 Posts
What bugs me about some EFI guys (no offense intended to anyone here) is when they say I can build a decent EFI system for the same price as a carb. BULL PUCKEY ;)

You may be able to build a decent EFI setup with used eBay stuff for about the same price as a TOP OF THE LINE BRAND NEW carb, but I can get an eBay carb for $100 too . . . so lets compare apples to apples here . . .

OK, rant over. :D
 

· Registered
Joined
·
1,975 Posts
Ive got a carb on both of my cars and if I could afford it I would switch to EFI, no questions asked. It also doesnt hurt that when I go turbo, the EFI will make the drivability and overall power production alot easier...either way, if you were going to just build a nice cruiser, a carb will serve your purpose more than well enough.
 
1 - 20 of 49 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top