# quadrajet question/help.



## RMTZ67 (Mar 12, 2011)

So I just finished the breakin on my car last weekend and all went well.Got to seat my rings this weekend. Question is, I have a newer quadrajet model that I have been using but not sure it's all up to par since its a store bought. ran decent before but after redoing my engine adding a 068 cam, ram air manifolds and 2.5 magnaflow exhaust I want to get all its gonna give me. Is there someone or place I can send it to tune it? And what other info would they need? altitude, compression? Carb # is 17057533


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## gtojoe68 (Jan 4, 2019)

I sent mine to QJet Power - 
https://quadrajetpower.com/


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## RMTZ67 (Mar 12, 2011)

gtojoe68 said:


> I sent mine to QJet Power -
> https://quadrajetpower.com/


did you have to give them engine specifics and or elevation?


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## gtojoe68 (Jan 4, 2019)

I did - I gave him the basics as in was in process of rebuild at the time. I mean - 400, Ram Air grind cam, 10:1 compression, manual shift etc. To really tune quadrajet, you would need to do some dyno pulls to check different metering rod sizes etc. Honestly, I 'm not as qualified as others on the forum to answer that technical of carb tuning. 

I still get a bit of std Q-Jet bog when the secondaries open up, maybe the top flaps opening too soon. but I have it for that sound a spreadbore makes. Love it.


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## geeteeohguy (Feb 2, 2008)

Cliff Ruggles. He literally wrote the book on Quadrajets.


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## BearGFR (Aug 25, 2008)

gtojoe68 said:


> I did - I gave him the basics as in was in process of rebuild at the time. I mean - 400, Ram Air grind cam, 10:1 compression, manual shift etc. To really tune quadrajet, you would need to do some dyno pulls to check different metering rod sizes etc. Honestly, I 'm not as qualified as others on the forum to answer that technical of carb tuning.
> 
> I still get a bit of std Q-Jet bog when the secondaries open up, maybe the top flaps opening too soon. but I have it for that sound a spreadbore makes. Love it.


How "hard" does your car launch when you hit it? I chased a bog problem on my 69 for a long time and had tried all the remedies mentioned in Cliff's book. I even made several of my own vacuum pull-off orifices to tune the rate at which it released and allowed the air valve to start opening. Nothing helped. Then I talked to Cliff and he mentioned that on cars that launch relatively hard, sometimes fuel can hit the back of the float bowl and splash up out of the openings where the secondary metering rods are and over into the air stream, causing a momentary rich bog. The cure is to find a way to create a seal at those two points to keep the fuel from doing that. That's what cured my bog. Something that's relatively easy to try is use a strip of black vinyl electrical tape on the gasket there, then poke the rods through the tape when you reassemble the carb. "Work" them a little to make sure they don't bind and will still drop when the air valve closes. If that fixes the problem, then you can make a more permanent solution. I just used a thin piece of aluminum to make a baffle with holes positioned in the right place and just big enough to let the rods go through.

Bear


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