thinking now of ditching the q-jet on '81

[pauld]

After considerable thought and discussion, I am now considering ditching the computer controlled carb and replacing with either an Edelbrock or holley which will be a standard setup and not computer controlled.
I wondered who else has taken this route and are you happy with ditching the Q-jet.
I was going to rebuild the q-jet, but now i am thinking that the computer control is more trouble than it is worth. Non computer carbs are easy to adjust by cpmparison and alot more straight forward.

Your thoughts please???


Paul.

 

[Jack]

Paul:
First, I’d check if there are any laws/regulations/emissions standards that prohibit such changes … check local & parliament. If it’s OK to make changes then consider this:

!. I dunno about your 81’s distributor. Seems like many 81’s did not have a “vacuum advance” … seems on some models the advance was controlled (in part) by computer. Prior Non-computer models had both vacuum & mechanical/centrifugal ignition advances that are both part of distributor. I strongly suggest you’ll need both. If yours is missing either … it is likely YOUR distributor can be retrofitted with the needed advance unit.

2. Your original GM intake manifold has mounting flange pattern for only Spreadbore carbs.

3. I suggest the Edelbrock 19xx series carb. It is a copy of the Non-computer Rochester Quadrajet and its mounting flange is same (spreadbore) as your computerized Qjet. Edelbrock’s 19xx series carbs cost about twice what their 14xx series do. Their 14xx series is a copy of the Carter AFB carb. Qjet has the “spreadbore” pattern … while the AFB has the “squarebore” pattern like most Holley & Demon carbs do. G’Luck.
JACK:gap

 

[Vette/Berlina-coupe]

-Study your '81/Repair-manual....

-Why not carefully study your 1981/Factory-manual to see if by simply disconnecting the wire going to the Carb./Solenoid-valve that you render the Rochester tantamount to a 1980 iteration (not having the integral/Solenoid-valve); --although i suppose you will then get a pesky dash-message saying "check engine". Actually, these are inherently much better carburetors than the Hollys, ---so try to work with'em...
~Bob vH

 

[MaineShark]

I'd agree with Jack. Just get a Q-Jet that is not computerized. Either get on off an earlier Corvette, or get a performance one like Edelbrock sells.

Joe

 

[Stallion]

I do have to second what everybody is saying. There is no better carb than the QJet. It is even in competition with some FI units. It is well designed, with primaries that are narrow for response and efficiency, and secondaries that are huge to really pack it in when you step on it.