Carb or Tbi?

[omillan99]

my 1978 chevy C20 is running great but the carb is giving me hassles, im thinking of doing a conversion from the carb to maybe a tbi. the carb i have is a holley 750 4 barrel with the double pumper and we've had it overhauled, but the secondary's get stuck alot. my engine is a 400 C.i. four bolt main with an rv cam, headers, edlebrock intake manifold, and its bored 40 over. i usually like to off road, so what do you guys think?? Stick to the Carb or Switch to a TBI??

[Fast305]

my 1978 chevy C20 is running great but the carb is giving me hassles, im thinking of doing a conversion from the carb to maybe a tbi. the carb i have is a holley 750 4 barrel with the double pumper and we've had it overhauled, but the secondary's get stuck alot. my engine is a 400 C.i. four bolt main with an rv cam, headers, edlebrock intake manifold, and its bored 40 over. i usually like to off road, so what do you guys think?? Stick to the Carb or Switch to a TBI??

Quadrajet

[BaggedBurban305]

after battling with electrical issues tuning injector sizing and a tbi chokehold i went carb.ditched my fusebox and ecu all together and wired everything from scratch.bought a brand new holley hp street 750 and honnestly its the best thing i ever did.

[chevy_tx89]

after battling with electrical issues tuning injector sizing and a tbi chokehold i went carb.ditched my fusebox and ecu all together and wired everything from scratch.bought a brand new holley hp street 750 and honnestly its the best thing i ever did.

im having electrical issues too im thinkn about switchn to carb will it bolt right up if its non vortec

[Pre-StrokerC150]

I swapped from TBI to carb also. Very happy with the results.

[chevy_tx89]

sooo it will bolt right up? what all goes into the swap ? fuel? ignition?

[Pre-StrokerC150]

Just the carb, intake, distributor and some basic wiring.

[BaggedBurban305]

a carb on a non vortec engine makes no diffrence than on any other motor except that vortec style intakes are usually a little pricier than non vortec headed motors.i spent about 1000$ converting to carb using all brand new performance oriented parts and the factory intank pump with a bypass regulator.

[BaggedBurban305]

honnestly if its a used carb rebuilt or not id just get a new one.switching to a tbi injection will be more expensive than just buying a new carb.if your tired of headaches tbi isnt the injection for you especially on a modified motor as i learned that the hard way.i wouldnt recommend any kind of fuel injection on a modified motor to anyone unless you can tune yourself.if you cant it will take a fair amount of money and a good tuner to get a tbi to fuel your motor properly but if you do choose to do it i would recommend holley's projection system as you can tune it yourself.down side is there 2 barrel only flows 670cfm and there 4 barrel over 900cfm i believe.

[omillan99]

oh alright i see, so what type of carb would you suggest??

[BaggedBurban305]

i would recommend 4 barrel holley hp street 750 vacumm secondary.they come with a nice silver ceramic coating finish and dont have the secondary flap allowing more airflow.i bought mine for just over 400 new i through ebay and i run it over a edelbrock airgap intake 1" open spacer and matching edelbrock aluminum heads.

[omillan99]

alright,i see. thats almost the same carb i have but it has mechanical secondarys.

[sldhd7]

Quadrajet, as Fast305 stated. When properly set up they they will be your buddy for ever!

[whitelightnin92]

second on my list would be an Edelbrock because the tuning is pretty close out of the box, first would be a Q-jet. i will never have a holley carb, theyre a pain in every category. they all leak and ive seen them burn vehicles up because of it.

[JoshTheCanadian]

Q-Jet IMHO.

[84c10tony]

Howdy, i got a quadrajet e4me rebuilt from carb master888 on ebay, the smog tech at the shop said it was good right out of the box (hard to do in socal) and the best he had ever seen, middle pricing, best workmanship! it has been running just fine.
good luck!

[2LNBLKTOP]

I swapped from TBI to carb also. Very happy with the results.

What all did you have to do to swap to carb? My 305 tbi is smokin like a bitch and can't find a replacement tbi. Think I wanna put my stroker and a automatic in her.

[Guss]

I was thinking of going carb on my 1993 suburban and my new roller motor very mild street 383 small cam all low end staying under 5,000 rpm 33in tires 373 gears stock converter in trans headers and all 3in exhaust.

[Justin_Inc]

my 1978 chevy C20 is running great but the carb is giving me hassles, im thinking of doing a conversion from the carb to maybe a tbi. the carb i have is a holley 750 4 barrel with the double pumper and we've had it overhauled, but the secondary's get stuck alot. my engine is a 400 C.i. four bolt main with an rv cam, headers, edlebrock intake manifold, and its bored 40 over. i usually like to off road, so what do you guys think?? Stick to the Carb or Switch to a TBI??

If thats your only problem, then get this
http://www.summitracing.com/parts/PRO-67155/

solve your secondary problem. why spend money to switch to an inferior fuel injection system only to have different headaches.. fix the **** ya got cheaper and be light years ahead!

[whitelightnin92]

If thats your only problem, then get this
http://www.summitracing.com/parts/PRO-67155/

solve your secondary problem. why spend money to switch to an inferior fuel injection system only to have different headaches.. fix the **** ya got cheaper and be light years ahead!

inferior? yeah right. get your head out of your A$$.

they can be hard to tune when highly modded but not inferior

[Justin_Inc]

they are 100% inferior. I know you hail the TBI setup, but the stock GM TBI setup is junk in all sorts of the name. Power, economy, etc can all be done just as well with a carb, plus have better fuel atomization than the tbi's.

It would be pretty hard for a TBI setup with a great tune to beat a properly tuned annular booster carb.

[whitelightnin92]

you are highly opinionated with your statements. give me some good reasons why a carb is better. i just think your a poor tuner and you run back to your lovely carbs that need to be tuned everytime the weather changes(not trying to sound like an ass here). tbi starts better(because it knows how much fuel to dump in VIA the coolant temp sensor, wich means cold and warm starts are effortless), idles smoother(if you can tune right) and it has better throttle response because there are so many more variables you can fine tune. you have 100% controll of the idle speed and have built in stall saver. the ONLY advantage with a carb is a few more HP on the topend. TBI is superior when it comes to lowend TQ aswell.

and if stock TBI is junk then lets compare that to a 100% bone stock 350 with a 4bbl quadrajet. TBI kicks its ass in all categories. i think those things wer putting down like 180 hp in 86?

[SierraDan]

The TBI in my Sierra runs perfect at 201K miles, starts fast even in winter and I never get less than 18mpg city. On my 86 Silverado I had a 500CFM Edelbrock Performer and it was all headaches with 160K on it. My Sierra feels stronger than that Silverado did and that truck had longtubes and 2.5" duals, a Lunati Voodoo cam Accel HEI distributor with a high output ignition coil. It could have used better heads but I could never get it tuned right, no matter whch jets I used and the choke would always stick open. I'm not the best at tuning carbs by any means but i've just always had better luck with my TBI, been perfect so far (knock on wood) so why mess with it? Like stated above if I want a built motor i'd use a 4bbl TBI unit like a Holley Pro-Jection or something similar. also heard guys having luck with TPI swaps on mildly built motors, i'm just no fan of carbs. I find it easier to tune EFI to make more power, economy and better drivability, I don't see why it's so tough to learn how EFI works and get the equipment to tune it yourself or fork over a few bucks for a pro to tune it.

[whitelightnin92]

they can be beaten easily by a good multiport setup, but not a carb. like i said earlier, the only place a carb is better than TBI is all out topend power, and thats not a concern untill you start turning super high rpms with it.

[SierraDan]

I'd chose a carb in a mud truck, like there are lots of guys with the old 22r powered Toyota trucks (2.4L, 22re is the same but EFI) they take mudding and I totally see why but for anything else i'd take TBI or any other EFI. In high school we build two dirt track cars, a 94 Escort 1.9 EFI and an 87 Accord DX 2.0 1bbl, the Accord we could tune and get more power out of it but the Escort we left the stock tune since it was a junker and not worth the money to tune it, and the Accord was faster, although it would have been anyways since it was a 5spd and the Escort an auto, but the point is that the carb made it easier to get the full power out of for cheap. But like I said for daily driver and 99% of the time, EFI anyday for me.

[AAKTM]

So I hope I am in the right place. I have a 1989 Chevy 3500 crew cab 4x4 turbo 400 trans 350 tbi stock.
I plan to use this to pull my 30 ft rv. It is gutless. If you guys would give opinions and ideas, that would be super.
I also have a 5 speed tranny I may put in.
Am I better off staying with the TBI or swapping to a 4 barrel carb.
I at some point may go with a 383 stroker, but not for a while.
I just want to be able to pull a hill at more than 25 mph

[topcok88]

If anything do a swap to something newer. IF you do go to a carb, be ready for the greater problems like: Cold Start Ups SUCK, Carbs work well at only one given RPM/LOAD range, the inability to change running characteristics due to altitude with out a extra set of jets in your dash! And the list goes on and on and on... Anyone who says a Carb is superior to fuel injection for a street driven vehicle is a fool and would rather tune his vehicle every Saturday due to the change is weather and density than drive his vehicle and enjoy it. Swap a LS1 or a 6.0LQ in it if anything. Good Luck!

[Guss]

Go with shorty smog headers DONt go long to many issues and a y pipe Flowtech is good and a tbi intake edelbrock do all tbi mods and a set of under drive pulleys . I should say First make sure it is in a good state of running good tune up and all stock stuff working as it should otherwise it will be an uphill battle. See tbi mods in the tbi section all so go to TBIcity.com

[Guss]

I will look I may have an ADS super chip for that I have a bunch left I have not looked at the box in awhile I will look to see if I have it.

[Bad Bowtie 91]

If anything do a swap to something newer. IF you do go to a carb, be ready for the greater problems like: Cold Start Ups SUCK, Carbs work well at only one given RPM/LOAD range, the inability to change running characteristics due to altitude with out a extra set of jets in your dash! And the list goes on and on and on... Anyone who says a Carb is superior to fuel injection for a street driven vehicle is a fool and would rather tune his vehicle every Saturday due to the change is weather and density than drive his vehicle and enjoy it. Swap a LS1 or a 6.0LQ in it if anything. Good Luck!

That's a bunch of crap, I drive mine daily and never fool with the carb at all. Hell all the OOBS had em from the factory and alot of em are still on the road.
I'm not saying a carb is superior to fuel injection, they both have thier own advantages/ disadvantages, but to say you'll have to tune for a weather change is just silly.

I drive it in the rain, when its 100* and never mess with it anytime. Sounds to me like you have never really messed with a carb before or just don't know how to properly tune one....

[whitelightnin92]

whatever you do do NOT get smog headers, they make less power than stock manifolds. you can get shortys and see good hp gains but dont get the smog headers. if it was up to me id run midlength headers, long tubes or Tri-ys. i acuallly have flowtech midlength headers on my truck and like them well. i actually went lean when i installed them untill i tuned for it.

[AAKTM]

I have no smog restictions where I live so none of that DEQ testing is required.

[SierraDan]

That's a bunch of crap, I drive mine daily and never fool with the carb at all. Hell all the OOBS had em from the factory and alot of em are still on the road.
I'm not saying a carb is superior to fuel injection, they both have thier own advantages/ disadvantages, but to say you'll have to tune for a weather change is just silly.

I drive it in the rain, when its 100* and never mess with it anytime. Sounds to me like you have never really messed with a carb before or just don't know how to properly tune one....
You live in Georgia, even in north Georgia the temps never significantly change. Here in Kansas it can be 90 degrees one day with 80% humidity and 40 degrees the next, and having the carb tuned for the hot humid weather then going to cold in a day will mess it up, when the weather got cold I had mine run lean from the denser air and not enough fuel. It depends where you're at, for crazy sudden weather changes i'd rather not mess with a carb. If I was in the south and it was relatively warm all year a carb would be fine. It doesn't get cold down there, when I was in San Diego for boot camp in was late November and at night it'd get down in the 50's and the So Cal people were in coats. I was like, "are these peopel serious?" because I was still in shorts and a t-shirt because that's nice weather for KC.

[topcok88]

That's a bunch of crap, I drive mine daily and never fool with the carb at all. Hell all the OOBS had em from the factory and alot of em are still on the road.
I'm not saying a carb is superior to fuel injection, they both have thier own advantages/ disadvantages, but to say you'll have to tune for a weather change is just silly.

I drive it in the rain, when its 100* and never mess with it anytime. Sounds to me like you have never really messed with a carb before or just don't know how to properly tune one....

This is actually not 'crap'. And yes they both have their own advantages... A Carb is honestly ONLY GOOD AT ONE SPECIFIC RPM/LOAD RANGE! And if you don't think you have to tune for a slight weather change, YOU KNOW NOTHING about carbs. Ever been to a dirt track race? Or a drag race? See those nice little DA calculators, temp gauges, and log books full of information from the past. In one night of racing a mod we had changed jets 4 times.... 4 TIMES!! Why you ask? Because TEMP, HUMIDITY, DA, and many more variables affect how a Carb reacts. RANT OVER!

[Bad Bowtie 91]

Yeah, in drag racing or whatever you might have a point.
But for streat driven vehicals it's not that serious, I mean for the 40 or 50 years that cars came with carbs, people just carried around jets incase it rained, or the temp changed???
Ever been to a Nascar race? how often do they change jets during a race? how about the night races when the temp has to drop over time?

Meanwhile, I'm still driving my carbed truck, it rained today but it's supposed to be sunshine tomorrow, I guess I better go change my jets and hope she runs agian.....

:looking:

[Fast305]

Yeah, in drag racing or whatever you might have a point.
But for streat driven vehicals it's not that serious, I mean for the 40 or 50 years that cars came with carbs, people just carried around jets incase it rained, or the temp changed???
Ever been to a Nascar race? how often do they change jets during a race? how about the night races when the temp has to drop over time?

Meanwhile, I'm still driving my carbed truck, it rained today but it's supposed to be sunshine tomorrow, I guess I better go change my jets and hope she runs agian.....

:looking:

Point is EFI DOES THIS AUTOMATICALLY, MANY TIMES PER SECOND!!! CARBS ARE STONEAGE TECHNOLOGY WHEN IT COMES TO CARS. TBI on a street car or truck is better than ANY CARB. There is a reason GM went to them.

I have had my fun with carbs and I am slowly going EFI on everything.

[cancritter]

tbi over carb anyday

[SierraDan]

There are reasons why EFI is everywhere, if carbs still worked for daily drivers then why not still use them on current production cars? It's because they're not efficient or convenient. Aslo why is it that most of the world's best performing race motors use EFI? Baja Trophy trucks, WRC, Formula 1 and even NHRA drag racers all use fuel injection, because it's better all around. You can tune a carb but you can tune EFI also, so why not run EFI? The only reasons I see to use it would be if you're racing a junker and don't want to spend money on tuning it up. I wouldn't run a carb even if I had an old classic or muscle car, i'd get a stock looking TBI system for ease of use, carbs be damned.

Yes i've owned carbed trucks, I didn't see what the big deal about tuning and rebuilding was, I thought it was a hassle and was glad to get rid of it. In my experience something was always a bit off, whether it be how it was tuned (extreme whether changes making it a bigger pain) or the choke was acting up or something along those lines. To me, it's just not worth my time and money.

[bclax1408]

they are 100% inferior. I know you hail the TBI setup, but the stock GM TBI setup is junk in all sorts of the name. Power, economy, etc can all be done just as well with a carb, plus have better fuel atomization than the tbi's.

It would be pretty hard for a TBI setup with a great tune to beat a properly tuned annular booster carb.


alright, lets put it this way:
what does a carb do? it opens it flaps and dumps in as much fuel as it can to get it to run right.
what does a TBI do? it has sensor and all that good **** that TELL it how much fuel yo use. sure, there are things better than a TBI like fuel injection, but i love them. my stock 93 4x4 with a TBI whoops the **** out of my buddys built 2wd thats carbed. both 350s.

but really, if your system is alreay carborated, dotn switch it. just get a new carb. quadrajets are really nice. got one on a mopar 318, work really good.

[Justin_Inc]

LOL, hating on TBI sure works alot of people up HAHA. :toolman: TBI is a great system for daily's/mild builds. Only reason i say carbs are better is from a performance standpoint. I've personally played with them all. And have been able to pickup hp/tq on a carb'd setup from TBI setups almost every time (in anything more than a mild build). Like anything they all have drawbacks (except MPFI). People need to relax abit.:stir:

[buellwd01]

i perfer a carb because there's only three thing u have to worrie about in a carb engine is not workin is the combustion,ignition,or the fuel. for the tbi engines it could be a computer,sencers etc. carb engines are easier to fix and maintane

[randeez]

been trying to dd my carb'd truck for a few weeks...kinda sucks, i'm going back to tbi soon. granted there are better carbs for a daily but my tbi before the swap was pretty reliable and shouldnt be to bad to tune

[carter442]

i tell you im 18 and love my tbi i also love my carb in my 72 442 and my sfi in my 95 beretta. everyone has its issues and positives my carb in my olds makes alot of top end power the low end comes from the stroke my tbi makes tons of low end torque and is awsome for offroad basically tbi is a self tuning carburetor it functions in the same manner except the injectors vaporize the fuel like injectors should do. sfi is great for overall driving and adapts even better than carbs and tbi u can take a stock engine add parts and it will adapt for them with no tune. now im in college for diesel trucks and jst took an electronics class the sensors on a tbi are truthfully prehistoric the only modern sensor on it is the tps and those are almost outa the door. the hall effect is replacing them. in six weeks i went from nothing to pretty much understanding sensors how they work how to test syumptoms and what they do im sure people who are older and have more experience can easily understand the tbi electronics i would still choose carb for all out drag racing or something that involves alot of top end power