Carbing an 89

[Kocher93]

I have a 1989 k5 with a stock 350 that has a tbi, I would really love to throw a carb on it, So after looking at it I was wondering if there is some electrical computery robot stuff that will prevent me from throwing on a new intake manifold and carb on it?

 

[onetonbb74]

The fuel pressure is the biggest thing, you will need a fuel pressure regulator that has a return. You can easily swap a hei dizzy and an intake with carb on that engine. There is no provision on the block for a mechanical fuel pump.

 

[Kocher93]

or could I get a new throttle body and call it good? Where could I find an aftermarket tbi?

 

[onetonbb74]

what is wrong with the one on there? Mine is used from an 88 350, works fine.

 

[Kocher93]

I really have no clue my friend has a stock 83 and it seems to be more to it than my tbi

 

[sweetk30]

you go carb you get less fuel mileage and offroad driving abilitys .

do some basic checks and read up a bit here first before you swap .

there is a efi section just below this section with lots of good info.

fyi i swaped in tbi for my 79k30 when i did a body swap from a 87 that had it. man do i LOVE it over carbed anyday .

oh ya and your in komyfonia so smog checks would be bad day for you if you swap in carb.

 

[ryoken]

I really have no clue my friend has a stock 83 and it seems to be more to it than my tbi

yeah, cuz it's Cally..... comp controlled carbs..

ummmm, don't you need to pass emissions? it wont with a carb...

FI blows a carb away unless your trying to make big power.. even that's a lie if you have enough money... most swap IN EFI..

 

[Kocher93]

Alright so whats a good aftermarket I can put on it then? I don't wanna spend 900 bucks on some edelbrock thottle body

 

[sweetk30]

stock reman unit will be all you can do basicly unless you get in to custom chip tuning and also make sure its C.A.R.B approved for cali emmisions.

like i said tho before you go tossin cash all over the place and screwin your self read up here a bit on tbi mods . there is a few good simple C.A.R.B. approved parts you can swap on and play with exaust a bit for much more bolt on power than just a bigger fuel dumping tbi unit will get you for problems .

 

[Stomis]

Whats with this recent rash of "How do I get rid of this tbi for a carb" threads?

You're going the wrong way. TBI is the upgrade to carbs not the other way around. Theres nothing wrong with the stock unit. With a tune, porting, adjustable fuel pressure regulator, and bigger injectors the factory TBI can handle north of 400hp.

 

[ryoken]

Alright so whats a good aftermarket I can put on it then? I don't wanna spend 900 bucks on some edelbrock thottle body

let's figure out what's wrong with the current setup..

first what are the symptoms/problems?

and is it throwing a code, the check engine light coming on? you'lll need to check for codes with a paper clip...

http://www.cfm-tech.com/gm_tbi_trouble_codes.htm

 

[blazinzuk]

If you are swapping to a carb because your buddys truck feels more powerful, then I think its for the wrong reasons. On a modded ( heavily ) engine a carb can make more power than a TBI (not fuel injection in general but the TBI is somewhat limited). But if your buddys truck feels more powerful there are a ton of questions I have for you

What gears?

Tire size?

Lift?

Engine mileage?

Overall engine condition?

Same questions for your buddy too. Answer all those questions and you may find its in your gearing or possibly his engine is newer or in better shape.

How long has it been since a tuneup?

That stock 83 ( if yours is stock) may have 3.73s and you have 3.08s, that will make a huge difference in the perceived power. Everything else identical the truck with the 3.73s will beat the truck with 3.08s

 

[Kocher93]

4.88
33x13.50
4lift and 102k original miles, my engine is in awesome condition my oil always looks like cooking oil.
Hes running the same stuff, his motor is has 20k more miles but he does have 35s.

 

[Kocher93]

also don't worry about the smog, imagine this is a 75 or older.

 

[ZJumper]

4.88
33x13.50
4lift

Holy crap that thing must feel snappy with that gear/tire combo. As stated before, you might want to do a full tune up:

Cap and rotor
Check and adjust timing if necessary
Plugs and wires
Air and fuel filters

The standard stuff

 

[Kocher93]

Holy crap that thing must feel snappy with that gear/tire combo. As stated before, you might want to do a full tune up:

Cap and rotor
Check and adjust timing if necessary
Plugs and wires
Air and fuel filters

The standard stuff

I already when through all of it when I first got it, its running perfect (as it gets) I just want more out of it.

 

[blazinzuk]

I already when through all of it when I first got it, its running perfect (as it gets) I just want more out of it.

Changing to a carb is not going to net you much at all if any.

Headers would probably do more

 

[ryoken]

not probably, definitely.. as we know, it's the first step in opening up the air pump...

OP... cam and heads dictate power, not what fuel supply it has.... start with a good exhaust... cranking up fuel pressure with an adjustable reg is the beginning of working the fuel end.. plenty of TBI mods out... spacers, salad bowl, etc...

but unless you get involved in changing the valvetrain out to something a bit more aggressive, which brings up other curveballs, it will plateau... TBI bumpsticks not being known for their performance, it's generally the limiting factor...

 

[sweetk30]

just for kicks when last time you changed fuel filter down on pass frame rail ?

i had a 88 tbi 350 and ran great but lacked bottom end power/tourqe to smoke tires. ( young and dumb ) changed the fuel filter and that thing would smoke a set of tires with out even trying .

amazing what a small restriction will do to the system.

 

[p0ps45]

I run a Holley TBI that's CARB approved on a 91 Blazer. It made some difference but I don't know if the cost is justified. I got it years ago on EBay for $350.00.