Quadrajet carb????????

[zbhover]

Hello everyone, today between the rain drops I was messing around with our 350 donor engine, just trying to get it running as good as I can while its still in the truck, which is a 1977 Chevy C-20 Camper special.

The choke is always closed on the quadrajet carb so I figured I’d take a look at it and see what I could do. I got out my Haynes manual to look at a parts break down of the carb to check and see if all the linkages were there and correct, etc…. Maybe it’s the bimetal heater too???

Anyways that’s when I noticed that my carb didn’t match the drawings of the 4MC/4MV or M4MC/E4ME series quadrajet carbs in the manual. The main difference that I noticed was the fuel line was going straight into the front of the carb instead of into the side like the drawings. So I wrote down the numbers from the carb which were:

Rochester Quadrajet
17058263
0938 BBC

I jumped on the internet to see what I could find and it looks like this carb was originally on a 1978 Pontiac with a manual transmission. And built 93rd day of 1978, and I have no clue what the BBC means??? From what I could find it’s an 800cfm and the original carb on the truck may have been a 750cfm????

Does anyone know a link to a parts break down of this carb or have one they could email me??? Or maybe which series or model # this carb is???

I also have a couple other questions:

If this carb is actually a higher CFM carb could I get any performance advantage with it???

Also would this carb have mounted to the stock chevy intake??? Or is it likely that I also have different/ Pontiac intake.

As far as I and the p.o. know this was the stock engine for the truck (casting #3970010) he had the engine and heads reman’d but reused the intake and carb that was on it when he bought it.

[zbhover]

I found one on ebay that looks simular and the number on the carb is the same except it was on an automatic. the link is:

http://cgi.ebay.com/ebaymotors/Rocheste ... enameZWDVW

and if that doesn't work the auction # is 250292353819

Thanks

bye

[zbhover]

After a few hours of searching I finally found the info and drawings I was looking for. I finally found one of these carbs on ebay and he had a model # with it so I searched for that model # and came up with the carb doctor http://www.carburetor.ca/carbs/tech...ajet-index.html

There is a BUNCH of drawings of all the rochester carbs on there along with a bunch of manuals, etc.

I found carb sheets for 75-79 pontiac carbs (104mb pdf 200 pages) and after searching it looks like the only car that this carb was put on was the 1978 pontiac firebird 400cid 4 speed manual and the carb model # is M4MC. The carb sheets show a few nice exploded views of the carb and list out the part# for various kits, gaskets and every part in the carb.

I also found an 79 page manual that covers that model carb, with lots of info

If anyone needs info on rochester carbs, I'd take a look at that link above..... Lots and lots of stuff

I think I'll keep this carb, it doesn't look like people are getting much from them off of ebay, I might go with a different intake, but I think I'll keep the q-jet.... But that will be another post.

Now if it ever stops raining here in central IL I'll be able to go back to working on it.... LOL



Talk to you all later

bye