EFI vs Carb

[PBXII]

I am building an engine soon. 351w, TKO 600 trans, Eagle internals, Eldebrach heads and intake. I am not set on these brands, just a starting point. Using the car as a daily driver and some "spirited" driving. I was pretty sure on EFI, but now looking at possibly a carb now. Just looking at options. I already have the fuel tank set up for EFI, but will change tank if necessary.

I have seen the oval and round air cleaners, & the 8 velocity stacks. Which is the be a configuration for the engine to breath the best in EFI and carb.

I don't have the engine yet, so doing homework now for the day I assemble engine.

What do you have and what would you recommend?

Many thanks. FS

[HOODEY]

I have nothing but efi is newer technology. I am still shocked that many people still use Carbs.

[Wayne Presley]

Here's a tried and true set up
351w
AFR 185 heads
Comp XE274HR cam
Edelbrock Air Gap RPM manifold

Top it with either a Quick Fuel SS750-AN carb or Powerjection III and enjoy.

YOu can also do the 8 stack and it will make more HP, TQ and have better throttle response that the carbs or top it with a set of 48 IDA Webers.

[Greg_M]

I have nothing but efi is newer technology. I am still shocked that many people still use Carbs.

So is a Prius but I'm not surprised many people still build an FFR. Just kidding. Carb vs EFI, it's a personal decision for sure.

Greg

[efnfast]

carb > all

it's easier to tune, easier to install, easier to everything.

No regrets here. (holley 4150hp, no choke)

[jlfernan]

Go with a carb. Just do a quick search here and elsewhere and all you see are people asking about different codes spit out by their engine computers and having problems with the mass airflow sensors and such. I have a carb, had it tuned properly, and runs perfectly. Starts every time, no regrets. Keep it simple.


http://img193.imageshack.us/img193/2561/jorgec.jpg (http://thefactoryfiveforum.com/private.php?do=newpm&u=111)

[Racer 28]

I would go with the PowerjectionIII, very easy to install, looks just like a carb, but of course runs like EFI.

[efnfast]

Go with a carb. Just do a quick search here and elsewhere and all you see are people asking about different codes spit out by their engine computers and having problems with the mass airflow sensors and such. I have a carb, had it tuned properly, and runs perfectly. Starts every time, no regrets. Keep it simple.



This.

As long as it's properly tuned (and you arn't trying to do something like tune at sea level, drive to 6000ft above sea level) it's a pleasure.

The biggest thing to remember is that there's no computer - if it's cold outside and you need to start and idle it at 1500rpm, your foot is the computer and needs to give it gas to idle.

[John F]

It's a personal thing. You can build a strong motor either way. If you are building for power, you can do it cheaper with a carb, as upgrading the EFI stuff and putting a chip in to make it all work gets expensive. It's nice having the computer tell you why it's running funny, though.

[Bob Cowan]

EFI Vs. Carb is a pretty standard question around here. They both have plusses and minuses. You get to decide what you want.

CARB + : period correct look. Inexpensive. Easy to install and tune. Can use a standard mechanical fuel pump.
CARB - : not very accurate. cannot adjust for changing conditions. If yu live in a hot climate, you should use an electric or high volume mechanical pump with a bypass regulater and a return line.

EFI + : Extremly accurate in all conditions. Self adjusts for altitude, temp, etc. because of accuracy, you usually get better fuel mileage and better drivability. You'll also get decreased emissions; IMO, that's always a good thing. If you have a radical engine with a big cam and lots of compression, EFI will make it much easier to drive on the street.
EFI - : Expensive. More complicated. Need to use electric or mechanical high pressure pump. Usually needs a return line. The learning curve can be steep. Not only in tuning, but in shopping, understanding, parts selection, and installation.

Life's full of trade offs.

As for air cleaners, the standard Cobra finned oval one is usually only 1-2" high. It's a real power robber. A 14x3-4"" round drop base filter looks better (IMO), and certainly performers better. The K&N filter top can also add some power, depending on your set up.

[Lex]

The more the merrier! Not just carb but carbs!
http://i177.photobucket.com/albums/w220/lex446/CobraProgressMay09005.jpg

[3kcarbon]

I wanted a old school car like the originals so I went with a Holly carb. If money isn't a issue and you want to be the class of the party get one of the stack injection setups. Looks like Webers but its not....

[MHCobra]

Here's a tried and true set up
351w
AFR 185 heads
Comp XE274HR cam
Edelbrock Air Gap RPM manifold

Top it with either a Quick Fuel SS750-AN carb or Powerjection III and enjoy.


Wayne, what hp & tq do you see with this set up?

[289FIA_Cobra]

There are so many factors in this decision and it's easy for all of us to make a recommendation but at the end of the day, YOU have to live with whatever you get.
I went carb for it's simplicity of installation and ease of tuning. I have all the required tools for this: screwdriver and vacume gauge... but in a pinch, you don't need the vacume gauge.

I have considered EFI in the future after having run carb since 2006. When I started to build my FFR, I didn't know if I'd like to stay with carburators and/or add a supercharger so I installed an external electric pump along with a fuel pressure regulator and return line. This gave me flexibility for an upgrade; I also set aside a couple of circuits on my I-Squared in case a computer is in the cards. :D

As of this year, I still haven't seen a need to go EFI. I've driven my 650DP Barry Grant to varying elevations in California and so far, have not had to touch my carb very much. The upgrade of the heads and cam did have me fiddling with it a bit, but at this point, I think it's set pretty well. My upgrade path is set though; to add in something like stacked injected setup such as Waynes, I would replace the fuel pump to a high-pressure style, and re-plumb the FPR for the new setup if needed. Wire up the computer and whatever else is required for the setup and I should be good.

You could do the same as I did and plan your build to be flexible for either type. Good luck with your decision. It's never an easy one but remember one thing: you drive this thing with the hood closed. ;-) (except when you're go-karting!)

[PBXII]

Thanx for all the replies. it seems carb seems to be the majority vote. I have the fuel tank set up as EFI, but no fuel lines from tank forward. What will I need to do to change to carb? I also have the Ron Francis FFR wiring kit installed, can't remember if it has the EFI harness or not, do I need to change anything there?

289fia, I agree what you said about set up for both carb and EFI. Which ever I go, it would be less trouble re-plumbing for the other.

I will keep you updated on the route I take. Again, many thanx, FS.

[DougR]

I went with the Mass-Flo EFI and haven't regretted it. Easy to install. No tuning. Just bolt on and go. Same performance at sea level and on mountain tops. The only thing I've done in 6 years is change the fuel filter.

[Wayne Presley]

Wayne, what hp & tq do you see with this set up?
390-400 RWHP and similar TQ with 10.5 CR

[Mesa Mike]

I started with EFI and 7 years later changed over to carb. Much cleaner and no problems. I used the same donor fuel tank and just removed the in tank pump and blocked off the return line. As I recall I installed a tubing to replace the in tank pump. I'm sure you can get the plumbing from many of the vendors.

[teebee9320]

I just want to subscribe seeing as how I am trying to make the same decision....I have been bouncing back and forth, but now my heart is set on a Mass-Flo system....I just need to find the money for it :confused:

[PBXII]

Thanks for all replies, now the fun begins!! I am going with a carb setup, replumb for carb, but have EFI also installed in case I decide in the future to go EFI.

Now, with all the great replies, the engine build starts. The car is basically a daily driver, with a fair amount of spirited driving.

351W, TKO 600 trans. Question, if you were building engine from a bare block, what would you use for the rotating bits and other internal bits and pieces?

Many thanks.

[Don DePontee]

From carb to injection on FFR-2224, unbelievable increase in performance across the board with increased fuel economy and I'm never going back to a carb!
Before:
http://i152.photobucket.com/albums/s173/CobraDon/FFR-2224/24%20Stack%20Injection%20Conversion/DSCN6597.jpg
And After:
http://i152.photobucket.com/albums/s173/CobraDon/FFR-2224/24%20Stack%20Injection%20Conversion/DSCN6983.jpg
Don

[Bob Cowan]

I started with EFI and 7 years later changed over to carb. Much cleaner and no problems. I used the same donor fuel tank and just removed the in tank pump and blocked off the return line. As I recall I installed a tubing to replace the in tank pump. I'm sure you can get the plumbing from many of the vendors.

The fue system is easy. Use a stock Mustang tank, just like FFR recommends. Use the stock type in-tank fuel pump, and return line. Use a low pressure return style pressure regulater right next to the car. There are a couple of advantages to this - you won't have to worry about vapor lock, and it's easy to upgrade to EFI later on. BTW, I saw someone on the other forum was selling a Mass-Flo system.

For a rotating assembly, I would use a cast crank, stock rods, and Hypereutectic pistons. Quality parts but nothing exotic or expensive.

Use a roller cam. These days, keeping a flat tappet cam alive is getting to be a real trial. It's like a lot of things - a little more money now, but saves time, money, and frustration down the road.

[R. Button]

another vote for Carb... Made the switch from EFI to Carb lost maybe about 2 mpg hooked it up just like Bob describes and it's run smooth ever since. Never a problem in the heat with vapor locking.

[Arch]

I posted this on a thread asking about all the acronyms associated with efi:

All of the initials, acronyms, 60 pin connectors, computer codes, etc. Are part of the fun. After watching these guys have extensive "fun" with these systems, I have flelt left out with my Holley carb. Each day I get in, turn the key and go, what fun is that?

So, keep asking questions, reading, and watching. Eventually you will be able to confidently spend large sums of money and join in the fun of trouble shooting one of these systems.

Me? I will continue to putt around with my old school carb and remain jealous.
Arch

[PBXII]

I drove a friends carb'd C***a, wow!! He switched from a troublesome EFI to carb, still tuning and tweeking, but what a difference!! The beast is more alive!! It has a stock 302 with a Holley carb. I forgot to ask which Holley.

Now time to get the engine built. I hope to get 400,000 miles out of mine!! I'll keep you posted on progress.

[Mesa Mike]

Be sure to use good fastners (ARP)for all internal components and use anti-seze lube and torque to the right specs. Felpro gaskets and seals and top of the line cam, bearings, etc. Enjoy.

[PBXII]

I agree, I have been going over a few parts catalogues and have seen the ARP hardware. I keep saying, "Rightytightyleftyloosey" over and over. The engine builder and I are going to go over all the components soon. Now, about the engine block, I have seen the 351 in vans, trucks, and cars, are they the same or cast different for the 3 different vehicle styles?
I am having engine built as a short block and will finish the rest in the shop.

[cobradawg]

I guess if you are looking for a real sixties look cobra, or building from scratch, a carb is fine. However if you are using a donor you already have all you need to go EFI, which means better gas milage and no tinkering. I'm EFI and I've not touched mine in 5 years of driving, and hey even NASCAR is going EFI!!

[kevin12973]

If you decide on a carb, I would suggest the quick fuel also. However If I were to do it over, electronic fuel injection would be under my hood right now. Been tuning my carb for a week now, pain in the but, ordering parts, changing jets, power valves, accelerater pumps, cams,nozzels, choke settings, idle air, secondary springs, jets. I would rather do it with a laptop and not have to open up the carb and get fuel all over the engine every time I want to change something. Not to mention its expensive to buy those little tuning bits. The air fuel meter was pricey too. My vote is go with a simple efi, not the complex stack efi.

[Bob Cowan]

The air fuel meter was pricey too. My vote is go with a simple efi, not the complex stack efi.

A good wide band sensor is a valuable tool, no mater what induction system you have. It may be a little expensive, but it's worth it.

Stack systems are no more complicated to tune than a central throttle body. It uses the same sensors, injectors, ECU, and the same software. The initial set up has a few extra steps, but they're not complicated, either.

[mike forte]

Hi FS,
Your build plan looks fine. Use the Eagle or SCAT 408 Stroker, Edelbrock Performer RPM heads & intake, MSD or Crane distributor & ignition, not to crazy hydraulic roller camshaft (always convert to roller for reliabilty), and a Holley 670 street avenger or Powerjection III. As for valve cover & air filter I mostly sell the Ford Racing Cobra valve covers and Cobra oval air filter.
NOTE: We dyno lots of customers engines and have seen a significant increase in HP & torque over most carbs. If you're on a budget then carb it and swap over in the years to come...

MIKE FORTE
FORTE'S PARTS CONNECTION INC.
40 PEARL STREET
FRAMINGHAM, MASS. 01702
508-875-0016
fax: 875-0032
cell:781-248-8946
Established 1981: Back in 1993, Mike Forte developed the original conversion of the Ford Tremec into a GM 5-speed. These have always bolted to OEM GM aluminum bellhousings without an adapter plate. The Early Ford & FE Tremec were also originals from Mike Forte. The Mustang firewall adjustable quadrant kit also is an original from Mike. His latest developments are external slave clutch release conversions & cable release conversions too. Now Tremec sells the GM TKO-500 & TKO-600 as a direct replacement thru their Elite distribution system. Forte's is one of 11 Elite distributors in the US & Canada that carries the complete line of Tremec transmissions including T-5, TKO-500, TKO-600 & T-56 Magnum. We also sell service parts and in house rebuilding.. Complete in house engine machine shop and engine dyno for turnkey engine/transmission packages.
Please call me with any questions.
Thanks for your interests,
Mike Forte



I am building an engine soon. 351w, TKO 600 trans, Eagle internals, Eldebrach heads and intake. I am not set on these brands, just a starting point. Using the car as a daily driver and some "spirited" driving. I was pretty sure on EFI, but now looking at possibly a carb now. Just looking at options. I already have the fuel tank set up for EFI, but will change tank if necessary.

I have seen the oval and round air cleaners, & the 8 velocity stacks. Which is the be a configuration for the engine to breath the best in EFI and carb.

I don't have the engine yet, so doing homework now for the day I assemble engine.

What do you have and what would you recommend?

Many thanks. FS