Swap or not?: Carby to EFI

[Advancedynamix]

Mega Squirt, then your covered for later enhancements.

[Bert]

Don, talk to Kartracer46. He can give you the best advice in this regard. He's rebuilt them, and would rather Carb a car than EFI, if I'm correct. He may be the one to bring you to the dark side.

Dark side? Carbs have been around a darn sight longer than EFI and by and large are bullet-proof. If you're lucky and they're stand-alone (no electronics) you can upgrade to Webers. You'll be able to get home with a hose and gas can on the hood if the fuel pump gives up.
What I did discover years ago was that carb vehicles don't readily start on ethanol-mix gas when temps are below 0 F. Something to do with not vaporizing adequately.

[garagedoorguy]

i got better mpg with carb and 4 speeds

[georgeb]

Dark side? Carbs have been around a darn sight longer than EFI and by and large are bullet-proof. If you're lucky and they're stand-alone (no electronics) you can upgrade to Webers. You'll be able to get home with a hose and gas can on the hood if the fuel pump gives up.
What I did discover years ago was that carb vehicles don't readily start on ethanol-mix gas when temps are below 0 F. Something to do with not vaporizing adequately.

I prefer carbs but the latest carbs like the 88-89 Festiva units are actually more complicated than EFI to get comparable mileage and emissions readings. My carbed '89 runs well but I foresee the day when it can't be maintained with the feedback unit.

[bravekozak]

To pass emissions with a carb, turn the screws in until it starts getting rough then back off slighly, add a bottle of Guaranteed to Pass, take the test. After you pass the test, turn the screws out until it starts getting rough, then back off slightly. All done.

[Damkid]

Personally if I actually owned a carb festiva, I'd convert it to EFI

[Bert]

I prefer carbs but the latest carbs like the 88-89 Festiva units are actually more complicated than EFI to get comparable mileage and emissions readings. My carbed '89 runs well but I foresee the day when it can't be maintained with the feedback unit.

Trying to computerize an otherwise purely mechanical device to try to make it something it isn't supposed to be is bound to cause problems and likely explains why the ultimate Festy switch to EFI. However there should be carb kits or aftermarket carbs that require none of that electronic control. Throttle should be all that's needed and perhaps if you're so inclined; automatic choke and seasonal air pre-heat.
The performance Austin Minis of yore had dual carbs whereas the standard versions had a single. Features like this are kinda handy to provide more fuel/air (no rev limiter!) if you install stiffer valve springs and a different camshaft.

[Christ]

I prefer carbs but the latest carbs like the 88-89 Festiva units are actually more complicated than EFI to get comparable mileage and emissions readings. My carbed '89 runs well but I foresee the day when it can't be maintained with the feedback unit.

Remove the feedback crap and cap the vacuum lines. The feedback system only includes a throttle kicker and a cutoff valve, as far as I can see, other than the obvious electric choke. The rest is all the sensors required to tell the ECM when to kick the throttle or cut fuel (DFCO, I presume).

Other than that, the Festiva carb is "just another carb" and functions exactly the same.

[Flw Sock]

I personally love carbs. I would give them a chance.

[sketchman]

Keep the carb, then later grab a set of these. GSXR owners seem to throw them away. Got mine for $55 and shipping on eBay.
Then "rev it and rev it and rev it until the valves come out and dance round on top of the bonnet."

[scitzz]

I would say stay carby, and learn some new tricks!

They came before EFI, so they can't be more complicated.

It takes learning new things to keep the brain young.

Learn carbs!

[Christ]

I would say stay carby, and learn some new tricks!

They came before EFI, so they can't be more complicated.

It takes learning new things to keep the brain young.

Learn carbs!

Most of us wish that were true... however, the venturi system used by carbs CAN BE very finnicky to things even as simple as changes in air temperature.

Tuning a carb perfectly across a large RPM range is nearly impossible without complexity. A ECM just requires a 5 minute re-map cycle (in some cases) to be effective from idle on up to 14+k RPM, and the injection system itself is actually about the simplest way to effectively introduce fuel to the air charge.

[Bert]

It's interesting that the older generation is leery of dealing with EFI (includes me) and the younger gen. is scared of carburetors. Good carbs are almost bullet proof. They have to be way out of whack in order for you not to get home and the lo-speed and hi-speed adjustment screws very rarely move or go out of adjustment without your help. Toying with an old GM Quadrajet full of watch springs, brass seats, needles and seals is not for the faint-hearted but in the case of Festys the parts list won't be very long.
That set of 4 carbs shown in an earlier post sure sounds like an excellent recipe for a fire-breathing dragon. Smooth idle gets to be a bit of a problem with that amount of air coming in but once the revs are up it sure is nice for when the motor is set up to rev another 1500-2000 rpm beyond stock. Old tuners used stethoscopes or a length of hose held at the intakes to adjust for a consistent sound from each carb.

[Bert]

Keep the carb, then later grab a set of these. GSXR owners seem to throw them away. Got mine for $55 and shipping on eBay.
Then "rev it and rev it and rev it until the valves come out and dance round on top of the bonnet."

How on earth would you come up with or concoct a set of intakes to house these carbs and have them bolt up to a B-series engine?.

[Christ]

It's interesting that the older generation is leery of dealing with EFI (includes me) and the younger gen. is scared of carburetors. Good carbs are almost bullet proof. They have to be way out of whack in order for you not to get home and the lo-speed and hi-speed adjustment screws very rarely move or go out of adjustment without your help. Toying with an old GM Quadrajet full of watch springs, brass seats, needles and seals is not for the faint-hearted but in the case of Festys the parts list won't be very long.
That set of 4 carbs shown in an earlier post sure sounds like an excellent recipe for a fire-breathing dragon. Smooth idle gets to be a bit of a problem with that amount of air coming in but once the revs are up it sure is nice for when the motor is set up to rev another 1500-2000 rpm beyond stock. Old tuners used stethoscopes or a length of hose held at the intakes to adjust for a consistent sound from each carb.

Much easier to just sync them with a length of vinyl hose and some transmission fluid LOL.

I've been working on bike carbs since I was a kid, done a few swaps onto cars, even one for an "emergency fix" onto an otherwise EFI car with bad injectors. (Turns out that if the ECM doesn't notice the injectors are bad and the A/F stays within spec, it doesn't turn the CEL on. )