apache
1/2 ton status
Curoius what was the first year of the computer controlled carbs on K5`s,Calif particulary if there was a 49 state and then Ca version.
CK5
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First year of computer carbs
- Thread starter apache
- Start date
Kenny78
1/2 ton status
Not positive, and I havent even seen a CCC carb on a truck out here. I believe the dual accelerator pump was '86
I don't have an exact answer for you, but I can tell you this. A coworker has an '84 GMC 2wd shortbed with the 305 and CA emissions, and the carb is not the computer type. The truck seems to be all original, save for custom paint.
apache
1/2 ton status
Interesting, my 84 K5 has a CCC with 02 sensor and the rest of the fun stuff,also have a 84 C20 that has no cat even from the factory. Must be required on "passenger type vehicles" like the K5 and not trucks till later or depending on GVW.
American84K5
1/2 ton status
My 84 has a pcm.
Isn't hooked up though.
I believe it controlled the choke and some other ****.
Isn't hooked up though.
I believe it controlled the choke and some other ****.
American84K5
1/2 ton status
Yeah I think mine DID the timing and choke at one point in time. 
badmix
1/2 ton status
I have an 84 K5 that is factory carbd. under the dash , way up, there is a box that looks like an ECU, I have no idea what it does. But when I got rid of the quadrajet carb for my Holley, I was told that I needed to change the Dizzy, so I got a Mallory Dizzy and it runs fine, been that way for years. No O2 sensors, etc.
So ya got me.
So ya got me.
It was at least '85, perhaps '84. First year it was even *possible* was '81, as all GM US cars had it, but AFAIK no trucks got it that early.
It was a CA only deal, I doubt CA mandated that setup specifically, more likely a change in emissions requirements that it corresponded with, I don't believe Dremu's brochures talk about the CA only trucks in regards to the CCC. Only way to know that I can think of is for those that have '84 and older parts manuals to see what year they are first listed.
People get ESC/EST and CCC confused. Truck CCC uses a carb with THREE electrical connectors (choke, TPS, Mix Control Solenoid) along with an O2 sensor, while ESC/EST was a timing-only deal, no special carb or O2 sensors. ECM for either setups was mounted in the same place later on (above glove box), while early ESC/EST was mounted near the gas pedal IIRC.
It was a CA only deal, I doubt CA mandated that setup specifically, more likely a change in emissions requirements that it corresponded with, I don't believe Dremu's brochures talk about the CA only trucks in regards to the CCC. Only way to know that I can think of is for those that have '84 and older parts manuals to see what year they are first listed.
People get ESC/EST and CCC confused. Truck CCC uses a carb with THREE electrical connectors (choke, TPS, Mix Control Solenoid) along with an O2 sensor, while ESC/EST was a timing-only deal, no special carb or O2 sensors. ECM for either setups was mounted in the same place later on (above glove box), while early ESC/EST was mounted near the gas pedal IIRC.
right Dorian, my 85 had only a 4 wire connector to the distributor, and would retard the timing by up to 12* by what I observed. The knock sensor was in the drivers side coolant drain pipe plug above the oil pan. I ended up bypassing the computer, by putting a jump wire between 2 of the electrical pins on the dist. connector, and adjusted the timing manually. My carb had a 2 wire hookup to the front pass side.
The truck was a 85 C20 w/ 7200gvw.
The truck was a 85 C20 w/ 7200gvw.
Kenny78
1/2 ton status
I think the carb 76zimmer had only had a dual volume accelerator pump, not full CCC controls. Havent had to get into one, but I think that this solenoid could either be bypassed or hotwired and it would be just like a regular carb, correct?
Lots of "AFAIK" on these carbs, but I suspect it wouldn't matter if you bypassed the dual capacity pump or whatever GM called it. What I've read about it seems that it's only a cold engine feature, so at worst it will not accelerate as well with the engine cold. Not sure how GM could have done this though, as engine vacuum and throttle position still are what govern fuel delivery on non-CCC vehicles.
No, if it still runs, it is not a PCM or an ECM, it is probably just the EST controller. EST doesn't make the spark, it just has the ability to introduce some extra retard from what the dizzy would otherwise be doing.
CCC never came on 49-state trucks. It appeared on some California models in 84 and 85 and was then replaced by TBI in 86.
Thunder
3/4 ton status
87 was first year for TBI in trucks. 1986 was still carb even in Ca.
pauly383
Daddy383
I'm in AZ , and have seen some CCC Quadrajets on 85's and 86's . Most of the 49 state trucks were like my 83 before that , no nothing but regular charcoal can vented Quadrajet on the few that had 350's , ESC spark and regular charcoal can vented Quadrajet on the majority which had 305's with the 9.2 to 1 compression .
I believe ESC/EST was across the board on the "high compression" 5L's in trucks (which is why we see it so much), and Dremu's brochures also back that up I believe. GM made specific mention of it in the specs.
I did end up disconnecting the acc pump plug (if thats what it was called) I put a 350 in it, and had to open up the jets to accomodate that, (Vortec heads, .450/.460 lift cam, and headers) and it accelerated very good. NO bog, or flat spot.
