Author Topic: 79 Formula Firebird 301 4 barrell quadrajet  (Read 3325 times)

Offline 79_Formula-Fbird

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  • 1979 Formula Firebird 301 4 barrel quadrajet
79 Formula Firebird 301 4 barrell quadrajet
« on: June 10, 2011, 05:01:13 PM »
my fire chicken has about 75K original miles on her and person I bought it from had it sitting off/on for 2 years.

Carb doesn't look bad--she starts every time, most without pumping pedal 2X!
Just 1/2 pedal and she roars to life...

I'm thinking it might be good to get the carb rebuilt due to occational black smoke at full throttle (which isn't that wonderful in a 301!) and a bit a fast idle like it doesn't know to throttle back once warmed up.
There is even some spark knock--mid octane is helping--when going up hills.

Which of the rebuild kits is best for this?
Found a guy at a car show who does the rebuild for $100 + $20 for part kit from O'Rilleys--he seems be one of last to specialize in them.  Since I know very little, not sure what to ask him/inquire as to the rebuild.  He does have a business card, older/retired, belongs to a local car club, lives near by, etc.

This guy did mention something about putting on a Edelbrock carb with a plate adapter.  Would that be better to wake up the 301?  OR does the intake manifold just choke on any more fuel??  For that matter, could bigger secondary jets do it some good??
« Last Edit: June 10, 2011, 05:05:02 PM by 79_Formula-Fbird »

Offline omaha

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Re: 79 Formula Firebird 301 4 barrell quadrajet
« Reply #1 on: June 11, 2011, 12:14:05 AM »
   I'd get pne of Cliff's SR kits. WAY WAY better than a kit from O'Reilley's. I think I would also get a throttle bushing repair kit. (comes with the special drill, the bushings and locktight and maybe some new screws for the butterfly plates). I think your runaway idle might be due to loose throttle shafts letting air bypass the plates. THe kit has high quality parts that you just cannot find anywhere. The accel pump's rubber material and the needle and seat are designed to be extra tough to withstand the new fuels today with the alchohol in them. Cliff has them special made just for his kits (or for sale seperate)
   Sure you could go with an Eldebrock carb but think about this. First youre gonna have to use an adapter so, more chance of vacuum leaks especially with the cheap stuff out there. Second, how much of a pain in the ass is the throttle linkage going to be to set up. With the original carb, you know that is gonna work. Third, the eldebrock has a "one setup fits all" concept that does not take into consideration the fuel curve requirements of any specific engine. In other words they set the carbs up with a "rich" fuel curve as to make them universal for many applications. they are just not trailored for a specific application like the original Q-jet. Forth, the design of the Eldebrock is "old" compared to the Q-jet which came out of the mid sixties, not the fifties. It is not as good at fuel mixing compared to the Q-j and its dual booster design. The Q-j works way better at low speed  and general street operation. Fuel milage will go down AND engine wear will go up due to the extra fuel cylinder washing tendencies. Ok just my .02  worth.
    A good friend of mine used to own a 79 firebird back in the 80's early nineties. Ran good and got good fuel MPG. Looked like "Rockford's" car with the gold color.

Offline 17058263

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Re: 79 Formula Firebird 301 4 barrell quadrajet
« Reply #2 on: June 14, 2011, 11:46:56 PM »
so is your 301 nutless will it do a burn out