Lacking power? Look at your carb

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1low4x4

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Well I am very glad to post this. I rebuilt this crate 350 about 6 years ago, and three years ago I started trying to get more power out of it. I had already put flattop pistons in it, so on went a set of vortec heads, a bigger cam, headers and Electric fans and lower gears, anything and everything I could do within my budget to make this thing go. But it never really performed to my expectations. It was always sort of disappointing. Until today.

A couple of days ago my carburetor which is a Quadra jet, started running like ****. The last time it was gone through was three years ago when I think a cousin put different metering rods and jets in it. So on Thursday I ordered a carburetor rebuild kit from Chuck's as well as his how-to book. Well I got the weekend off unexpectedly, and though I have not received the rebuild kit yet I decided to watch some videos on YouTube. Those how to videos got my courage up enough to pull out one of the spare quadrants I had and terret down to see what it was all about. I'm a pretty talented person, I've always shied away from quadrajets because of how complex everyone has always said they were.

In the video the guy showed three main reasons the Quadra jet wouldn't perform. One reason was that due to the little tang coming off the choke being stuck, you would never get the secondaries open. The next reason was The carburetor didn't have the green ride from the vacuum card to the secondary air door linkage on top left of the carb. The third reason he gave was that under the airhorn one of the bigger airfield tubes could have fallen out and could be laying in the fuel bowl.

So I pulled my car up off my engine and the first thing I noticed was that my secondaries were locked shut. That little tank coming off the choke had them locked and though it is supposed to unlock when the choke warms up, my choke does not work. The second thing I noticed was a rattle, and when I looked down into the secondary holes past the air doors down on top of the butterfly was a cap infinitive Button just laying there. Now it's been at least five or six months since I've changed out the distributor, so I know that button has been there ever since. And I know that the secondaries have never opened because if they had that button would be down in the engine.

So then I noticed I didn't have the green rod on top, I added the rod, removed the tang locking the secondaries, and when I pulled the airhorn off sure enough one of the thicker rods was laying in the fuel bowl. I fix that too and put it all back together And when I put it back on the truck holy ****. My truck feels like it has twice the power. I'm sure reconnecting that air Rod under the airhorn helped the stumbling but having the secondaries operating, it feels like a damn race truck now. To put it into perspective, I bet if I had taken a quarter-mile time before and after, easily I would have shaved off a solid three seconds. That's how much quicker and crisper this truck moves.

So I'm glad I did all those upgrades because now I'm reaping the benefits of them with a good running carb!!!
 

1low4x4

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1low4x4

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crazy4offroad

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Holy **** auto-correct totally b0rked that 1st post lol. Man it sounds like all the mods you've been doing over the last year even though each gaining you a little have still really been held back by the carb problems. Did you just stick the bleed tube back up in its place or did you put any threadlocker or epoxy on it to hold it in place? If not it might drop out again. Post a link to the youtube vid you used, I have a quad I want to put on mine. I went through it recently but always hungry for info. Start saving up now for a new pair of back tires lol :cheers:
 

Quadrajet Power

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Haha, autocorrect was funny, but I got what you were saying.

I always leave off the secondary block. Unless my customer specifically request to be there on a restoration.

The large tube that fell off is for your pullover enrichment. Basically it works like an accelerator pump for the secondaries. with it out, it would cause a stumble.

Glad you got it running good. I can email you some tuning sheets if you need anything.
 

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