edelbrock carbs

[bblockss]

I have another carburetor question. I have 2 Rochester qjet carbs that have both been rebuilt but are still giving me problems. I have a 67 Chevelle SS with the 396/325 (with auto trans.) and I am considering replacing the Rochester with an Edelbrock model 1901 carb. I have read both good and comments about the Edelbrock carburetors. Can anyone give me advice as to making the switch or should I try another Rochester? I'm trying to keep the car as original as possible and yet make it drivable. I have the stock intake manifold on the car and don't want to change that.
Thanks for any advice.

[69 chevelle]

If memory serves me correctly, Vick Edelbrock bought the patents for Rochester's Quadrajet. So when you buy an edelbrock carb it is essentially the same platform just dialed up to a specific set of jets and CFM. What problems are you experiencing? Maybe one of us can help steer you in the right direction.

[bblockss]

Originally Posted by 69 chevelle

If memory serves me correctly, Vick Edelbrock bought the patents for Rochester's Quadrajet. So when you buy an edelbrock carb it is essentially the same platform just dialed up to a specific set of jets and CFM. What problems are you experiencing? Maybe one of us can help steer you in the right direction.

Thanks for responding. With the one carb I have the biggest problem is too much fuel. The Chevy garage that last worked on it replaced the idle mixture jets and worked on the car for 2 days. They have one jet turned all the way in and the other one turned out just a little and at idle the car still runs rough and is getting too much fuel. I have to power brake it just to keep it running.
The other carb that I have I just tried before storing the car for the winter. So I only drove it twice. It works alot better from what I can tell by just 2 test drives, but will still require a little tweeking.
I'm just thinking it might be best to start with a brand new carburetor instead of one that's 37 years old. From what I've read about the Edelbrock 1901 it should be a direct replacement. My only hesitations are cost and on another site folks were really slamming the Edelbrock, saying that they work great the first year and then fall apart.

[68chevelle]

well, the idle mixture jets your talking about on the first carb, arnt really jets, they are just idle mixture screws. all they do is control the amount of fuel at idle only. are you sure it is getting to much fuel, and it not just that they arnt getting enough with the screws tured so far in? they sould probably be about 2 turns out. usualy you can turn them two and three quarters out and thats a good starting point and adjust them from there. if it is getting to much fuel, it could be the actual jets, they are inside the carb, and or the main metering rods. you dont have to change just the jets to make it run leaner, you can run the same jets and a bigger metering rods and it will lean it out because the bigger rods are displacing more fuel, or run a smaller jet with the same metering rods, cuz it has a smaller hole to let the fuel through. the other thing could also be the float. if it is out of adjustment it can also cause the carb to flud. and the final thing that is a big problem with quadrajets is the throttle shaft in the baseplate. where the shaft goes through the baseplate becomes worn so much that it creats a leake and lets extra unmeatered air into the intake. thus leaning the AF out. and its basicaly imposible to get a car to run good if it is leaking there. you can either take it and have new bushings put in or find another baseplate that already has new ones or is stil good, but that is probably the most commen problem and cause of problems with qadrajets. hope this helps some.

[bblockss]

Thanks, I'll try your suggestions before I give up on the Rochester completely. The baseplate issue sounds like it could be the problem. I'll go through each suggestion though and check it out one at at time. I probably won't get to it until spring when I get the car out, but I do appreciate your advice.

[69 chevelle]

IMO the q-jet is the most reliable carb available it just requires a little more working knowledge of the carbs internals. do an internet tech search for q-jets, theres a lot of information out there. I use to run a Holley 3310 for BB cars then got a matching numbers 2029200 for my SS convertible out of a 427 Impala, it has just slightly larger jets than the ones for 325, 350 horse cars. Once I started running Rochesters after I learned rebuild them, and understood how they worked, I find they are bulletproof, they rival even todays high tech fuel injection systems. my .02cents

[69 chevelle]

68 has a point about the baseplate, however it is highly likely you could have a vacuum leak as well based on the description of your current problems. How does your exhaust look, smell?

[molhannah]

I have a 68 Chevelle that I tried to keep stock since it's rebirth a year and ahalf ago. I spent about a month and $200.00 to have my original numbers maching carb rebuilt and dino'd to match my engine, only to have it fail again after 6 months of weekend driving. I went to ebay auto parts store and found an Edelbrock new for $150.00. I'm running a 350 4-speed with posi and for the first time since the restore it smokes them both. It is now putting out the true power this motor has. I say go with the Edelbrock. Also I'm useing the original cast intake. Good luck with your decision.