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Discussion Starter #1
I've got a stock 350 in my LeMans and looking to upgrade the intake and carb. I've pretty much decided on the Edelbrock performer series 2156 low rise. I have been looking at Holley 650 cfm carbs, does anyone have a suggestion as to which one I should go with?? Looking primarily at 0-80783c (4150) and the 0-80555c (4175)
 

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I just picked up edelbrock performer rpm duel plane intake. I went with their carb thunder avs 800cfm. Can't give you a review since it's not on yet. Ran into problems installing headers. Got next two days off and no rain in forecast if I get it on ill let you know.
 

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What's on it now?

Hint: On a stock, or near stock engine there is nothing that will out-perform a factory cast iron 4bbl intake with a properly set up Quadrajet, or a tri-power. Period.

All the aftermarket "pretties and shineys" are just that. Pretty and shiny. But they're also slower.

Bear
 

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I second that with Bear. The factory quadrajet cast iron manifold has been proven time and time again to be one of the best picks, especially with a stock or mildly modified engine. Invest in a good replacement Q-jet carb. Small primaries bores are great for gas mileage. Kick those big secondaries in for power - and a sound you won't get with the Holley you are thinking about. The Q-jet is rated at 750 CFM or the later 800 CFM. I installed one on my 1976 Lemans which was a factory 2 barrel 350 CI. More power, awesome sound when the secondaries opened up, and could get 21 MPG cruising at 70 MPH with stiff (as I recall) 2.73 or such. Use a good after market open element air cleaner - the bigger the better.

Just my opinion on this one.
 

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Discussion Starter #5
It is a Rochester 2G with divorced choke, and the stock 2 barrel manifold. Most things I have read say that the Q-jet is a tricky/temperamental bitch.
 

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Discussion Starter #6
Also the smallest Q-jet I have seen is a 750 cfm which by any of the calculators is more carb than needed based on cubic inches and rpm without any other mods.
 

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The Qjet will work fine on your 350. They even used them on the OHC six. Many Chevy 350's, Olds 350's and Pontiac 350's and 326's came with the Qjet. When they are right they work amazing. Great throttle response and fuel economy. Usually it is the accelerator pump and/or throttle shaft bushings that give them the notorious bog. Also stay away from the later "electronic" Qjets, they are the only ones that have wires going to them so they are easy to identify. I much prefer a Qjet to the Carter AFB or Thermo-quad.

Find yourself a good core and contact Cliff Rugles to get it redone( if it needs it).

Cliffs High Performance Quadrajets :: Qjet Carburetor Rebuild Kits, Parts, Quadrajet Rebuilding, Quadrajet Parts, Bushing Kits, Carb Tuning
 

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I will admit that in order to make a QJet run well you do have to know what you're doing and think a little bit. My 69 GTO is an honest 11-second street car (best so far, 11.86 @ 113 mph) that I also drove on the full Hot Rod Power Tour this past summer - all 2300 miles of it (there and back). It has an 800 cfm QJet.

Don't believe everything you read out there on the Inter-tubes. Even here. :nono:

Bear
 

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As Bear stated, 750 CFM is not too big. Same as I had on my stock 350 I mentioned earlier. You can get a good rebuildable core cheap at most car swap meets if you go to these. Ebay has quite a few and one up there now is a rebuilt NAPA Q-jet for $111.00. There are many more cheaper that need rebuilding. You want to make sure you get the Rochester Q-jet and not the Carter. You also need to make sure that you get a Pontiac Q-jet so your carb/gas pedal cable will work with it.

Saw a video that was 16 minutes long on the web on rebuilding the Q-jet. Might give you and idea of what you are getting into OR as Bear suggested, either contact Cliff Rugles for a rebuilt unit, price on having your core rebuilt, or parts to rebuild yours. Shop around a bit. It is really not all that difficult a thing to rebuild. There are also several how-to books on the market on how to rebuild the Q-jet. You will find most members here advise any Pontiac Performance enthusiast to get a copy of Jim Hand's book How to Build Max Performance Pontiac V-8's. You can get it on Amazon.com and it has a section on Q-jet rebuilding and modifications.

You should be able to get a cast iron Q-jet intake cheap at a swap meet, craigslist, local trade paper, etc.. If it were me, I would not pay more than $25 for a Q-jet rebuilder core and then go through it -but I know what to look for and how to rebuild them so that's to my advantage. Last swap meet I was at had a ton of them in the $15 -$25 range. You can always get a cheap one, tear it down to see what your getting into and then decide what you want to do. Its all about fun and learning.
 

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These guys are steering you in the right direction. I swapped out my 2 bbl Rochester for a cast iron 4bbl intake and a Qjet. I bought Cliff's (of Cliff's High Performance) Qjet rebuild book, then I bought a rebuild kit, jets, rods, hardware from him. I told him what I had and he was able to sell me exactly what I needed. This was my 1st rebuild so it took me some time and I made many mistakes. But after all my screw-ups, I can easily take one apart and put it back together with confidence.
 

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Discussion Starter #11
Since my last post I talked to the people at Butler Performance and they suggested I go with the Edelbrock 2156 Performer intake and the Holley 4175 0-80555c(which is a Qjet replacement). They said it was a good combination. I am not ruling anything out or knocking anyone's setup, just trying to gather info and be a little informed hopefully before I make any purchases.
 

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The people at Butler know Pontiacs, so you can put stock in their suggestions. The factory intake and Q-jet is just an option or suggestion because it is a great factory piece that works well, and sometimes better, than aftermarket pieces. For us who do a lot of our own work and build/rebuild our rides, the factory combo saves money and we know the ins and outs of rebuilding a carb.

That said, buying a new intake and carb is a simpler bolt on/no fuss installation. The aluminum intake looks good when you pop the hood. I suggest you find a clear coat that is made for your intake to preserve the finish. The manifold unprotected will oxidize and dull out. Top it off with a nice big open element air cleaner with chrome top, and you have a nice look. Dress your engine up with chrome valve covers, some nice spark plug wires and wire looms, and you'll have a sharp looking engine.

Keep us posted on your results. If you go with the Holley and Performer, make sure you come back with a post (maybe a photo or two), even if it is weeks from now, to let us know how the combo works on your application, any problems encountered, and how the car's performance has improved. This way, the forum has your post to reference in the future if another reader is seeking the same advice or application.
 

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Discussion Starter #14 (Edited)
I found someone local with a Rochester Quadrajet supposedly functioning for $100.00. He says the #'s are on the main body GM 17054779 and on the front 17053289 and there is a circle with a # 6 in it and to the side of that a #9. It has electric choke and a side fuel inlet. Or is there a resource I can consult?

Can anyone decode the #'s and let me know if this is on I should be interested in?
Or is there a resource I can use to find out?
 

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Discussion Starter #15
I found the casting # chart at Cliff's High Performance but not sure which of the above 1705 #'s I should use in decoding.
 

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You could use that, but being that it is for a '77 Chevy, the inlet comes in from the passenger side, instead of the front like a Pontiac carb. You can do better for less money, I'm sure.

The thing with a Quadrajet is that it's only as good as the last guy who worked on it. It's a VERY good carb and you will not do better (or any where near as well) with the other combinations you've thrown out so far. Unfortunately, they're complicated and guys do stupid things to them trying to out think the factory. Cliff wrote the book on Quadrajets (literally!) And if you follow his advice and give him a call, he'll walk you through it and you'll have a trouble free carb that will last for years.

$.02

Chuck
 

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Found a website Carburetor Parts & Kits for Carter, Ford Motorcraft, Holley & Rochester Carburetors which decodes the carb. Seems to be a 1975-1979 carb, but you want to be sure it is a Pontiac 350, 400, 455, and not a 301CI.

You may also want to make sure the carb is for an automatic versus a manual transmission as there may be some differences in linkage as you may need an attachment for your kickdown cable to the transmission. Not sure on this, but looking at different Q-jets on Ebay. Look at your throttle linkage brackets to match up.

NAPA used to carry a master list of Q-jet carb numbers that could identify the carb as well.

Just found a blog that says the 17054779 in a circle is the main body part number and not the carb number, 17053289 was the part number for the top, and there was another number "17057502" on the side near the throttle linkage. THIS seems to be the ID number location, so get that number from the seller and see what it is. If the carb has the same numbers as what I have found here, 17057502, it was a 1977 Chevy Q-jet 350 CI 180 HP, AT.
 

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I have my 73 GTO that has had several carbs & 5 different engines in it over the life of the car. I now run a 462 with E-heads a performer RPM intake a RA IV cam (crane blue print) SRP forged pistons & eagle H-beam rods. I have tried several crbs with this combo, a 750 Holley HP carb, an 800 duel feed Holley, & am here to say I am back to my Q-jet. I run a 79 800 cfm Q-jet that I have played with & has some of the tricks from cliffs book in it to. My car is 3650 lbs & haS 3:73 rear gears & I run consistant 11:50's. I have had very good luck with the Q-jets over the years. One thing you have to remember is the Q-jet is a carb that adjusts the fuel needed & air by itself as needed by the demand. Thats why they can use them on so many different engines from a 6 cylinder to the biggest V-8 around & it still tuns great. Use the Q-jet , but buy Cliff Ruggles book about Q-jets & read it from cover to cover & then rebuild your Q-jet for your car. You'll be very happy when you decide to go with a Q-jet.
 

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Discussion Starter #19
What should I expect to pay for a cast iron 4 barrel intake? If the $100 is not good for the Qjet what is the going rate and those as well?
 

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What should I expect to pay for a cast iron 4 barrel intake? If the $100 is not good for the Qjet what is the going rate and those as well?
I probably got lucky, but I bought a date code correct (2 weeks prior to my motor date) intake for $125.

It's odd talking about paying 100 bucks or more for a Quadrajet, since we used to be able to pick them up all day long for $5-$10. It's not that $100 is too much these days, but you really want a Pontiac carb if you can get one, since the inlet needs to come in from the front, not the passenger side.

Other guys can tell you for sure, but Cadillac and Buick/Olds may have a front inlet, too. Check Craigslist, Ebay, swap meets, etc. And I'm sure you'll find what you're looking for.

Chuck
 
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