Quadrajet Questions

[WESTOF7]

Im thinking about keeping a qjet on my camaro its an 86 canadian z28 non ccq with the dual capacity pump controlled by coolant temp would it be worth rebuilding and modifying this carb? can the dual capacity pump be eliminated? i also have 17086246 quadrajet that i took apart and there was no apt? it seems like it has no provision for the apt from the factory?? would this carb be a good candidate for a performance rebuild? im also trying to find out if any third generation camaro's came from the factory with a regular m4me with no dual capacity pump but cant seem to find any information if they ever did. canadian models? exports? i have the stock carb off my 75 camaro 7045202 that appears to have the first variation of the apt are these carbs really that bad? sorry for the long post any feedback would be greatly appreciated.

[omaha]

I am not familiar with the dual capacity pump controlled by coolant temp. How does it work? How do you identofy them? Sorry cant help with that but, the 17086246, is this a design that uses the early casting design (like a '71). If this is the case then the apt would be built into the base-plate. The apt is adjustable after you bust out the plug in the base plate. (between the idle screws) But sometimes it is "froze-up" If you can un-free it you will be somewhat lucky.

   As far as the 1975 carb is concerened, yes they are not really worth messing with unless you have a total restoration back to stock.  THey were a one year only carb. I only have one of these carbs, actually they are hard to find and get some of the parts for, but still they are not woth that much unless for the resto deal and not too many people are resto-ing anything from 1975. As far as I know all q-jets on the 3rd gen camaro's were E4ME. That is only from my experience as far as I know.   I like the 17086246 would be best for a performance build. By the way i just found a really good chevy type large bore carb in a strange place. Right on top of a mopar motor in a one ton Dodge van from 1985. Hey its a chevy carb built in the mid eighties; just something to think aout.

[Cliff Ruggles]

The accl pump solenoid can be left unhooked, and/or block off the passages under it.

To date all 76 and newer carburetors withe the later APT design I've worked on had the APT system in place.  Some early 76 units still used the aneroid located APT and auxilary power piston deal, but no exceptions otherwise that I've seen.....Cliff

[Schurkey]

I am not familiar with the dual capacity pump controlled by coolant temp. How does it work? How do you identofy them?

I don't know about Canadian carbs,  the accelerator pump doohickey is most commonly found on NON COMPUTER-CONTROLED  pickup trucks in the early-to-mid 80's

Full accelerator pump shot when cold, partial accelerator pump shot when warm.

Looks like the connector for a mixture control solenoid.  Different color.  One's grey, one's blue, if I remember correctly.  I forget which is which.  Look at a mixture control solenoid connector, and the accelerator pump electrical connector will be the OTHER color.

[WESTOF7]

are there any side effects to unplugging the accelerator pump solenoid or blocking it off? ex running rich, lean etc? if i blocked it off would i have to change anything else?

[omaha]

Ok, so the auxiliary accel pump has only one set of wires going in the area of the accel pump.
Ok, now that I have that picture in my mind, I have actually seen them but not too often.
Interesting.

[Cliff Ruggles]

No negative effects that I've seen.  It has nothing to do with "running rich", it only reduces accl pump shot on a hot engine.....Cliff