Quadrajet manifold with edelbrock or holley carbs? Any issues?

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Octane

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Is the one hole then just a square opening that the butter flys open to the voided space rather than shaped ports on 4 hole?
It just obviously lets the square carb sit on the mounting for qjet?
Yes,just a big square hole over the qjet manifold so edel. will fit
 

75gmck25

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I’ve read in a couple different tests (Enginemasters?) that an open one hole adapter can improve the performance of a dual plane. The increased volume and straight shot of air flow works together with the dual plane. It’s not a big increase, but
I have definitely considered trying it.
 

fast 99

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Biggest thing is long term reliability and simplicity. Although Qjets are fine, age, ethanol, and sitting are an enemy.

That's actually one of the reasons I prefer Carters over Hollys. When Holley bowl gaskets age they tend to leak. The Holley carb previously listed is probably fine, Carters are less money. The last few Carters I installed worked fine and were jetted ok out of the box [infrared tested]. As always with carb conversions you will have to adapt it to the application, few are a direct bolt on.
 

AuroraGirl

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So I Did NOT realize this was my thread LOL

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since obtaining my TH350 agate from the gravel under it and his Qjet looking like that, and off screen the Distributor both was not pointed anywhere logically(advance), the weights were rusted, and the Thing was not likely stabbed correctly, and the vacuum lines are alllllll over the map, with missing emissions but the hoses not matched to where htey need to go, a EFE valve thats frozen shut on exhaust, and that choke being... im not even going to try and understand what happened there.

He had a "guy" who knew how to rebuild a carb and set things up. I Decided that it will wait for another day, and my dad said he had drove with the ends off the axle once or twice because he thought some noise had come from there, which makes me think this NP203 has part time conversion, which also makes me think the noise was a TH350 about to get-got in a heavy 3/4 ton truck no lockup converter, decent amount of miles, 4_ years old, and probably wasnt running right and that probably made it the weakest link of that dynamic.

BASICALLY. RIP that drivetrain.

He uses a sag 3 speed for a ballast on an old... lawnboy? one of those old horizontal shaft belt tractors with rigid frame etc etc.. told him to go get a column shifter tossed in and he can use that lol... he didnt htink it was funny after he originally was like "not a bad idea" then I mentioned trying to find and then adapt that shifter into that auto truck. lol
 

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