I have an 84 TA with a '92's L98 350. Stock 9.3:1 compression, cam, heads, ect... please read mods at bottom of post
I was running the Q-jet with the fuel mixture solenoid hooked up, but recently disconnected it. Everything else is connected... TPS, ignition, ect..., but it seems to run better with the fms disconnected (especially during winter).
I get less gas mileage, ~18 highway instead of ~21mpg.
I intend to reconnect the fms now that summer is here, but I haven't had the chance to yet (the land lord frowns upon open hoods in the communal parking lot ).
My questions are:
-Does it run better disconnected because I went from a 305 to a 350 and the extra fuel compensates for the increase in displacement?
-The carb is just old (it was rebuilt twice since I had the car, ~5years and itself is ~13yrs old) and has run out of it's 9 lives?
-Something I'm missing?
-CC Qjets for 82-88 350's any different from those on 305's (like cfm, jetting, ect)?

I was intending to get a new CCQ-jet, probably from www.carbruetion.com AKA Carbs Unlimited, who seems to have a nice selection of stock replacements, but I won't if I don't have to. Even at $350+$35 core charge, if I can save money I will. Thanks for any answers and opinions.http://www.carburetion.com

 

No difference in the Q-jets from those years. I doubt their is even a difference in the chips. Fuel tables do not exist in those ECMs as far as I know. It simply maintains 14.7:1 air/fuel ratio at part throttle and goes to whatever your jetting allows under WOT. The reason it runs better is you are giving the engine the optimum air/fuel ratio for power all the time.

I would however grab some DR or DA secondary metering rods and a F-hanger or below.

I went from a 307 to a 455 oldsmobile in a friends cutlass and kept the CCC q-jet. A set of secondary metering rods from a 454 truck and a primary jet change really helped the way it ran.

 

IIRC, 3rd gen 350s where never carburated. But anyway, it's possible your Mixture Control Solenoid has gone bad. The CC q-jet should work fine on a 350- lots of guys on the board have done it and are pleased with the result. You shouldn't have a problem with lack of fuel if the carb is jetted correctly. Try bumping up the jets/metering rods so that way you'll have power when you need it but still keep a good air/fuel mixture from the MCS. Get a dwell meter and check the MCS and if it is not working properly, replace it and then look and changing metering rods and jets.

 

I was referring to ccQ's on pickup trucks, and the like for a 350 calibrated ccQ-jet. Something in that time had to have a 350 in it... right? Wouldn't they be just a plug and play replacement?
If not, rejetting and metering would probably be the only route huh? Anyway, thanks for the replies so far.