TBI VS CARB

[willbro]

Whats the main advantage to this swap TBI TO CARB -more power or ?

 

[mikeru]

The main advantage is that because it is computer controlled, you can more precisely tune with TBI. This can not only increase power but can also increase fuel economy.

There is so much information on the web about the advantages of fuel injection over carbureted engines. TBI is fuel injection, so even though most of the articles out there talk about port or direct injection, much of that also applies to TBI.

 

[HemiLonestar]

Whats the main advantage to this swap TBI TO CARB -more power or ?

That can happen, but more to the point you can change things. Completely stock (and running correctly) that TBI will get you better mileage, smoother power delivery and better mileage than the carb that preceded it. Unfortunately it cannot account for or be changed for parameter changes (head upgrades, cam swap, boost, etc) and also seems to have a spotty record for reliability. Upgrading intake, exhaust and cam will require either a carb & distributor swap OR swap to an aftermarket EFI, be it TBI or port.

The main advantage is that because it is computer controlled, you can more precisely tune with TBI. This can not only increase power but can also increase fuel economy.

There is so much information on the web about the advantages of fuel injection over carbureted engines. TBI is fuel injection, so even though most of the articles out there talk about port or direct injection, much of that also applies to TBI.

Unfortunately he is referring to the OEM TBI around 1989ish. ZERO tunability.

 

[mikeru]

That can happen, but more to the point you can change things. Completely stock (and running correctly) that TBI will get you better mileage, smoother power delivery and better mileage than the carb that preceded it. Unfortunately it cannot account for or be changed for parameter changes (head upgrades, cam swap, boost, etc) and also seems to have a spotty record for reliability. Upgrading intake, exhaust and cam will require either a carb & distributor swap OR swap to an aftermarket EFI, be it TBI or port.


Unfortunately he is referring to the OEM TBI around 1989ish. ZERO tunability.

Fair enough. I have no real experience with TBI other than when I once owned a '91 Camaro with a 5.0 TBI engine. Guys in the Camaro forum talked about tuning those but I never ventured there. Thanks for clarifying that.

 

[David Vandercook]

Whats the main advantage to this swap TBI TO CARB -more power or ?

Swapping TBI to carb is the best thing you can do. The more black boxes we throw in the trash the better life will be.

 

[Jeepwalker]

Most guys who grew up on EFI forget all the negatives of carb'd engines, and even guys who haven't driven carb'd vehicles forget about some of the reasons car's went to EFI:

-Poor cold operation & choke performance,
-Running rich a lot and stinking up the garage, reducing plug life,
-Finicky tuning (some carbs),
-Acceleration lagging or bogging when the accelerator pump isn't working right.
-Carbs don't tend to last as long as EFI (bushings/seals/float valves may/will need replacing etc)

Those are the negatives because most car and truck owners were not real good at fixing or tuning their DD vehicle's carburetors, and then they'd run out of spec with the issues above. But carbs are completely analog and can operate great when tuned properly. To the guy who knows what he's doing and doesn't mind and and can deal with the issues which come up, such a knowledgeable owner can quickly remedy & make corrective tweaks to get a carb running good again ...which you can't (not so easily) with TBI's. Some types of carb's are simpler than others.

Unless a guy is running Ignition Points & a vacuum advance, there may still be an ignition module, which is an electronic "black-box" of sorts. And aftermarket Ign modules can be a source of problems too..so yer not totally out of the woods from electronics with an Ign module. Although OEM ones are pretty reliable. But when they DO fail, there's usually no warning, and the vehicle is just 'dead' in your garage ...or worse, on the side of the road. I carry a spare ign module in my GM OBS tk...because I've had ignition modules on various 80's vehicles fail a couple times over the yrs (going down the road of course!). When they fail, carb or no...yer down to walking. And just about every Classic Car ower I know has battled aftermarket ignition module failures. They don't seem that reliable. I'd stick with an OEM one if I could. And aftermarket EFI's from wathing people I know who've installed them, don't seem all that reliable (compared to OEM EFI).

To the guy who wants a set-it-and-forget-it driver, EFI makes sense. For the analog gas-loving "Tweaker", carbs and old-school factory ignition can actually be fun and run forever and you don't have to worry about fuel tables and computer mumbo-jumbo, lol (if yer not into computers). And you can adapt to larger HP mods. No EMP is going to take you out (although wrap your coil in tin foil)!! LOL. I wish manufacturers would unlock their computers to 'tweaker' after x number of yrs.

So there's good an bad. Hey! You could always go with an 80's Computer-Controlled Carb system!! Best (or is that Worst?) ..of both worlds! ha ha. I actually liked the CCC systems. I must be the only one.

 

[Docwagon1776]

Edelbrock sells an aftermarket TBI set up that's tunable, but the money isn't really worth it for these, IMO. Once you're dumping in that much cash, might as well look at doing a magnum transplant.

What you can do is have the throttle body ported and some light headwork if you want something that's cheaper, gets a bit more power, and doesn't require as much of a time investment.

 

[Jeepwalker]

..Or the time.

I know a couple guys who've sunk a LOT of time getting their conversions tuned to the point where they are reliable and working good. They're not always the 'take-out-of-the-box-and-turn-the-key' product some think they are.

I'm sure they are continuing to get better....