swapping to carb

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mustangluvr8993 said:
ok i got a 91 gt mustang 5.0 and its fuel injected and i was wondering how much work it would be to swap it to a carburated motor. what should i need? thanks for the help


Check this out:


http://www.jason.fletcher.net/default.htm

that place answered alot of questions i had, and its pretty straightforward. im loving doing my swap.. i sold all my efi junk, and selling it bought my carb, intake, valve covers and a few other things :nice:


i havent seen him around in a bit, but crazypete helped me out alot as well.
 
By the way, just to help out...

youll need to run new fuel line. the way im doing it is buying a roll of stainless braided line, because the hard aluminum line i bought proved to do nothing but piss me off. the aluminum is cheaper, but its a pain. youll also have to chose a fuel delivery method (either a mechanical pump, or an electric pump) if you go with a mechanical pump, youll need a pump, and an eccentric. if you get an electric pump (im running a holley blue) youll need a regulator to adjust the pressure, and on both applications, an in line fuel filter. my engine bay is so clean now that i have gotten rid of everything (im keeping the heater, power steering, and all that, the only thing i got rid of was the A/C) moved the battery to the trunk, stripped the engine bay, and am getting ready to paint it. ill try to add stuff in here as i go to help ya out.


oh, and since you have a roller motor, youll have to get a distributor (if your car an auto or 5-speed) from an 85 stang that was originally carb'd with a STEEL gear (thats if you have a 5 speed) if you have an auto, check out thwe link i posted above
 
Like FarBeyondDriven said if you decide to go the carb route you can sell the EFI stuff and it will just about pay for everything for the carb route. Check out that site it looks like a lot of good info.
 
mustangluvr8993 said:
ok i got a 91 gt mustang 5.0 and its fuel injected and i was wondering how much work it would be to swap it to a carburated motor. what should i need? thanks for the help
Once again, why?
Carbs are great for the track and make good power. Step on the pedal and flush - it's a gasoline toilet!

EFI RULES on the street for a car that is driven in all kinds of weather, up and down mountains and gets great gas mileage. EFI will make just as much power as a carb and be easier to drive on the street. If isn't hard to tune if you know what you are doing.

There isn't a carb made without computer assist that can do all those things as well as EFI can. The only possible exception would be the IDA or DCOE Webers which cost major $$$ - like $3000 for 4 each IDA 48's and a manifold.

Here's a book that will get you started with how the Ford electronic engine control or "computer" works.

Ford Fuel Injection & Electronic Engine Control 1988-1993 by Charles Probst :ISBN 0-8376-0301-3.

It's about $20 from Borders.com see http://www.amazon.com/ . Select boo...any better with a carb than it will with EFI.
 
jrichker said:
It isn't hard to tune if you know what you are doing.

And have a decent savings acount, and alot of time to trace all the gremlins you will encounter with 13 year old wiring.



jrichker said:
If you are adverse to reading books, the car won't run any better with a carb than it will with EFI.


But did you think that maybe he wants the simplicity of running a carb? I wont get into the arguments over which is better, they both have thier strong and weak points, and ive read every post i could find were it was debated (usually by knowledgeable people like you, Michael Yount, and Crazy Pete) And i made my choice based on the 40,000 "surging idle, no start, and all the other misc threads that people have with the old wiring. If my car doesnt start, i want to be able to look, and actually see if im getting gas or spark. I dont want to sit there with a multimeter, and test light for hours trying to figure out which wire is shorting to ground, or what relay is not working all the time.

So many people say "EFI is better", but it is ultimately based on what the owner wants out of the car. mine isnt a daily driver, and i will deal with losing a few MPG because im building a car for horsepower, and simplicity of maintenance.
 
pb_paulie_b said:
What we have learned. EFI for everyday use and carb for weekend users:)


I agree. I've personally never had any trouble from carb's other
than small leaks here or there sometimes. I don't even mind a
daily driven car with a carb. I personally don't preferr a car
that runs absoblutly perfect, i like a nice loud cam, rough idle,
a car thats a little bit naughty, thats what hot rodding is all about.
And unless you put a huge 750-850ish carb on your car(Which is
by far way to much for a 302 anyhow), i don't really
think your going to notice to much gas miliage loss over a cammed,
EFI car with large injectors. If you want a nice, quite ride that runs
like a top all the time, gets great gas miliage and has really good air conditioning, for god sakes get you a damn Honda! :)
 
Beyond the arguments (both good and bad) it all depends on what you are going to use the car for. Look up posts by crazypete, Rick91GT, Michael Yount, Daggar and JRichker concerning carb vs EFI. Thats how i made my decision. either way, there are people here that will root for either team, and you should be able to get plenty of help either way. Good luck with whatever you decide
 
Yea if your going to be driving the car alot, i would stay with the EFI definatly. But if your car is only driven mybe a couple times a week just here and there and you put it on the track a good bit. Go with the carb. Trust me, when something goes wrong and it wont start, wont run etc., your going to know real quick which one is the best in the "Ease to work on" category. But EFI for daily driver, Carb. for track car or little driven street car.
 
ok well i will probably only drive it on the weekends. ok so i think im going with the swap then. and actually i think im swapping it to a 351w. is the computer thats in it going to work still? plus another question i have is how big of carb should i use? id like to have to car into low 12's how high 11's. what kind of intake too?
 
for a high built 302 with a cam, use a 600-680cfm. For a beefed up 351 use around a 680-720 based on the cam and intake choice. Intake is also totally based on what you want the engine to do. YOu want a high rpm screemer? Use a Victor, you want low end trqu and grunt, use a RPM or a Weiland Stealth Ram. But it all depends on what you want the engine to do.
 
pikappaphi said:
I switched from a supercharged EFI to dual quads on my 95 cobra... it runs great, is more reliable than before, and looks badass. Check it out here...

http://www.insane-motorsports.com/


Your a better man than me. I have had 3 dual quad cars, 2 big block Chevy's and a built 355 small block. They were all plug fouling untunable pigs that all ran 100% better when swapped to a single 4bbl.
 
FarBeyondDriven said:
i havent seen him around in a bit, but crazypete helped me out alot as well.

You rang? :D

Been snowed in for a long time now and sorta fell away from the stang. But now with spring around the corner, I'm all fired up for it. Greasing down the entire bottom cause I "GASP" noticed a spot of rust down there!

So here is my input for the carb vs efi debate. EFI is a good system but costs a lot of money to tune and has a great many points of failure: fuel pump, FP regulators, dozens of sensors, injectors, wiring....as my esteemed colleage mentioned, its all 13 years old now. Plus you change something and now the EEC has no idea what to do with all the air. Well, now you need a recalibrated MAF, new injectors, another fuel pump....all $$$. I remember seeing pages of "which maf/injectors/TB should I run" threads. Also the uqiuitous "why wont my car start?" threads.

With carb, you have 3 points of failure: the carb, it's fuel pump and your ignition system. The fuel is easy enough to measure, the ignition can be tested with a timing light. The carb? I can replace my entire fuel metering system in the same amount of money it takes to replace a single MAF. I upgraded my heads? rejet = $5. EFI = new injectors $180 + MAF $200 + TB $100 (?), maybe new fuel pump = $75...well you get the idea. The jets take about 5 minutes to change while installing all that takes much longer.

Now about failure....when my efi died on the road....well, thats it. I'm getting towed home for a 1 week probing session to figure out which circuit is not cooperating. Last time my carb died (3 times now since I've converted 4 years ago, 1 intake leak, 2 carb base leaks, all fixed within 10 minutes once I got it home), I sprayed carb cleaner at it and restarted it.

Plus, you can stare at your EEC and you will have no idea what it's doing. Now you can stare at your carb and its very understandable. Levers, springs, pumps, cables, all stuff you can grok. If something goes afoul, your really can mcguyver a paper clip in there and drive it home.

If you dont like what your eec is doing...tough. You can get a chip or a tweecer, both $$$. If you dont like what your carb is doing, you walk up front and turn some screws.

Finally, daily driving. I DD this carbed mustang for 2 years and I have no complaints. I mean winter driving too (hence the greasing I mentioned above). Most of the folks that talk about non idling cars and pigs over carburate. Vacuum signal is EVERYTHING. People are so used to bigger is better and they slap a 750 on a mild 302 and then complain how their car has no throttle response. I run a 570 vacuum secondary on a custom cammed afr165 headed 302. Talk about throttle response!! It really pegs you into the seat, gets over 20 mpg, starts on the first or second turnover. Vacuum signal is EVERYTHING with a carb.

So I hope I put in a good argument for the carb side of things. Let me know if you need any help with your conversion if you decide to go for it.

Good Luck!

Pete