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Discussion Starter #1
How can I find out what year my 305 is? It was transplanted in my 68 Chevy panel wagon in 81 from a Firebird.

And, how do I find out what carb is on it? Looks to be a Rochester, 2 barrel, has BC next to fuel inlet, but all I can find with BC is 1 barrel. Carb either needs rebuilt, or if there's a good cheap option, replaced. I'm not looking to smoke the tires, just a good reliable old truck.
Thanks,
trapperjack
 

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Hates: Liver. Loves: Diesel
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On the driver's side of the carb there should be a stamping number. Give us that number and we should be able to at least tell you the carb info.
 

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Visually it looks like a 2GV, from 1974.
That´s the nearest I could get looking through Doug Roe´s
book, ROCHESTER Carburetors.
 

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Discussion Starter #5
Below is a photo with the number.
Yes, that's a wood screw holding the manual choke cable. The golf tee and wood screw are only 2 of the wonderfull add-ons my uncle did. They do serve the purpose, though.
Thanks for the replies,
trapperjack

The number was on the passenger side. Couldn't find anything on driver's side.
 

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Personally I´d trash that carb and inlet manifold, find something more seviceable.
Doug Roe reckons most of the stuff on carbs that old is too far gone and not available.
Let that motor breathe.
 

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Hates: Liver. Loves: Diesel
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The 170 indicates that its 76 or newer. The next two digits (58) indicate the year of 1978. The next digit (1) is the emissions code. I think it means 49-state. The next digit (1) indicates the chevy motor division, and the last one (4) means probably an automatic transmission.

Rochester USUALLY followed those rules, but not always. At least they always follow the year code pretty well. Its possible that a 1978 carb sat around long enough and made its way onto a 79 engine, but that would only account for a small percentage.
 

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Buick Hybrid Guy.
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I'm not a numbers expert when it comes to finding stuff like this but when I need a carb rebuild kit I'd get it off the carb. I think it's a 7 or 8 digit number on there. get it cleaned up and you'll find it on the main body of the carb.

Look on the pass. side of the block where it meets the head. There will be a pad that has numbers on it. You'll be able to look up the info on the block from there.
Maby someone here has a link to a site that has all the block ID's on it?
Good luck,Scott~
 

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malc said:
Personally I´d trash that carb and inlet manifold, find something more seviceable.
Doug Roe reckons most of the stuff on carbs that old is too far gone and not available.
Let that motor breathe.
Normally I'd agree with you, but on this one, that carb is probably supplying more than enough. The heads and cam in that engine are probably so anemic that adding more won't do anything.

My guess is that its the 160-hp version at best, but probably the 125 or 140-hp, so the 380 cfms he's getting from that 2-jet is more than he needs :)
 

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Discussion Starter #11
Thanks ya'll. Getting it narrowed down. Advance auto says it's a mid 70's Chevy. No telling what my uncle did. Swapped in the 305 in 1981 from, he said a Firebird with 24,000 miles. From what I can find here, pontiac didn't make a 305, but did use some Chevy 305's. He was very excited about it having a "Pontiac" 305 as opposed to a Chevy 305 for some reason, though he did say it bolted right up. I just don't know what to look for or ask for in the way of parts. I'm not going to build it up right now, I just want a smooth running, dependable driver. The carbs gotta go though.
Champion Reman has a #3-737 for $99 that looks to be a replacement for this one. anyone have anything good or bad to say about that?
Thanks,
trapperjack
thanks for the pics malc
 

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Buick Hybrid Guy.
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Much past 1973 GM went into... Mono mode... They used SBC's in pontiac's and others. Smog and emmissions regulations pleagued them to the point they forogot about how to build brand specific engines.
3.8 Buick engine's went into a host of makes
SBC did too.
2.5L went into everthing from LLV (postal trucks) to Camaro's. Yuck.
Be sad to get passed in a postal truck in your 82 camaro ;)
Anyhow....
A rebuilt carb might help.. .but I'm sure there's more problems than the carb. Golf T's don't belong as vaccume caps :drunk:
Just kiddin...
Look into the health of the engine before sinking too much into it.
~Scott
 

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Discussion Starter #13
One problem I'm up against is that I just don't know where that carb came from. It may have been on the firebird when they swapped in the 305, or knowing him, he may have found it on the side of the road and stuck it in. He was driving this everyday...to WORK....until I went and picked it up. Did I mention he just turned 90? He definately has a "make it work" attitude. Why buy spark plugs when your neighbor just threw his out? He'd sand the tip a little, regap, and if it screwed in, he'd screw it in. First thing I did was change fluids and spark plugs. Had 4 different brands, and even one of those "no gap" jobs you see now. Ran like a dream after that, but carb started leaking, and accelerator pump is going, etc.
I assume all that stuff he had capped with golf tee's and vac ports looped over to the next one are for emmisions stuff this truck doesn't have?
Thanks for all the replies,
trapperjack
 

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Discussion Starter #14
Looks like it's either a 78 or 79, at least the carb. Was there anything special about a Firebird 305 vs a Chevy 305, different heads or something? My uncle made a point of it being a "Firebird" 305, and the head mechanic at the Chevy place saved it for him and put it in himself at his home shop. Or did my uncle think that because it came from a firebird it must be souped up.
Thanks
trapperjack
 

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Back in ´84 I had a ´78 Camaro and that came with a Q-Jet on it´s 305.
A regular Q-Jet not those feedback things.
Surely a Firebird never came with less than a four barrel ??
 

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ATA Welding Technology
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My 305 came stock with a Rochester Quadrajet feedback carb on it. I recently yanked everything going to the puter and swapped out for a regular Quadrajet and now it will go from 0 to ticket in no time flat! :evil:
 

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happy with 2GV

Wanted to encourage you to stick with it and rebuild the 2GV. The kits are available- just search your part number from passenger side of carb on the internet. You can get an original manual PDF from www.tocmp.com

These carbs were used for decades, were designed with simplicity as a primary concern and provide rock solid reliability.

I have a 68 pontiac Le Mans 350 with a 2gv that could not be a more reliable performer(cold start, idle, accel-you name it). I would never put on a demon, holly whatever and take all the time to dial it in thinking I would be better off.
 

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Discussion Starter #18
Well, I had the rochester rebuilt. Hooked everything back up and tuned a little. Super smooth idle, ran like a scalded dog. Still had a little hesitation on takeoff. If you didn't feather the pedal, it would die. But ran great other than that. By the way it stumbled before the rebuild. Went on a 40 mile round trip, and performed great. Started and stopped several times. Got back from the feed store, killed it unloaded feed. When I started it after that to move it back around from barn, it would barely idle, very rough. Gas around base of carb, flooding. Took it back to the guy who rebuilt it and said that something had washed in around the spring at the filter and replaced filter, seat and needle. No flooding now, but can't get smooth low idle. Barely runs. High idle is fine.
sorry so long, but what else could cause 1) the stumble on takeoff and 2) the rough idle?
thanks,
Jack
 
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