Before I get started: Tri5, I am no longer using the CCC system and yes, I do agree it is the best way to go and I understand it's functions extremely well. So now that is out of the way.....

When I bought the car I was getting horrible gas mileage (12 highway) and after completely rebuilding the CCC and replacing ALL sensors the carb is running so rich there was gas coming out of the tail pipes after the engine rebuild.

I traced the problem to the computer itself using the shop manual and in anger this is what I did.


I've replaced the distributor and I have my Bowtie Overdrive TC lockup kit on order. My question is -- what carb do I go with? I would rather go with a Quadrajet but right now it's a little out of my price range. I have a Edelbrock 1406 (mechanical secondary) and a Holley 750 (vacuum secondary) that need to be cleaned and rebuilt but they are both very good working carbs.

I have everything already purchased for a Quadrajet so that definitely helps, but a SMI Quadrajet will set me back $400 after shipping whereas the Eddy and Holley will cost about $200 to buy the rebuild kits and required accessories.

Personally, I'm leaning toward the Eddy in the short run just so I can get the car back on the street. I would prefer to use the Holley but I'm afraid the carb is just to big for a stout little 305. Any opinions?

I'm open to all suggestions/opinions. I'm not a carb expert by any means but I know my way around them and know how to tune them to a degree.

Heck, I even considered going with Demons' new Street Demon but for the same money I could have a Quad.

1. Quadrajet from SMI ~$400 I REALLY want this carb, but it's pricey
2. Edelbrock 1406 600 cfm ~ $200 after I buy the parts needed and rebuild
3. Holley 750 ~ $200 after parts/rebuild but I'm afraid that it will be too carb

 

2 quick pictures of the carbs I have to work with.

Edelbrock. 600 cfm, mechanical secondaries


Holley. 750 cfm, vacuum secondaries

 

Edelbrocks don't have mechanical secondaries. They have a mechanical butterfly in the throttle body, but secondary flow is controlled but the air valve butterflies in the main body.

You don't indicate what you've got for an intake manifold. If it's the stock intake, you're either going to have to replace it to run a square bore carb like the Edelbrock or Holley, or use an adapter that will decrease hood clearance and often leads to sealing issues.

Or, for less than an Edelbrock or Holley plus an intake manifold will cost, you can get a rebuilt q-jet: http://www.summitracing.com/parts/SUM-210216/

Since you have a 5-speed, none of these choices are ideal. The best non-computer carb choice for you would be a double pumper/mechanical secondary Holley. 600 CFM should be fine for a 305.

(Is there a new CC q-jet advocate on the Board called "Tri5"??? )

 

I wouldn't use that 750 unless you went with a bigger motor. I vote a Holley 600-650 mechanical secondaries at the most.. or look into Proforms carbs. They're decent for the money spent if you want it new.

 

I would not run either of the carbs you have. Sell them and turn the cash into a more suitable one.

I'd suggest this one:

http://www.summitracing.com/parts/HLY-0-6210/

IMO the all-around best replacement carb for a typical street motor. Not least because, IT FITS THE CAR with a minimum of hacking. It even fits your stock air cleaner and fuel line. You'll need the right TV cable linkage to go on it, which you can get here www.tvmadeez.com You can even get an electric choke kit to put on it, that wioll hook right up to that feature of the car's wiring.

You can get them on ebay sometimes, refurbed by Holley, for a good bit less.

 

I meant five7 - it was about 2 am when I wrote this after being in the garage :-)

I have an Edelbrock RPM intake so the bolt pattern will work for anything.

Thanks for the advice but I found a very good Quadrajet local to me that looks very good and it came off a guy's perfectly running 63 Chevy. I bought a few pieces to run a fuel pressure gauge so everything should be good to go.

 

i have edelbrocks on 3 of my motors now. and one of them is a 600 cfm on a 310CI motor. and it runs great.