First real drive! Not tragic but not good. I think I need carb advice.

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Chris64

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So I've been checking off items to make this thing drivable and nothing's been easy.

Lights; I had no lights and no single problem. A few cut wires, a few chewed wires, a few bad bulbs and a few bad connectors and even some bad bulb sockets. I know have full lights (outside) blinkers, brakes and even reverse. Each one on each side was a fight.

Suspension; I had one broken shock and no others and a leaking steering stabilizer. I now have 4 new shocks and I have a steering stabilizer (but I'm waiting for that since I might need to do some steering surgery).

Brake fixes; new soft lines. I'll probably be replacing them for longer lines and I'm wondering if I should just replace the master cylinder because it's 50 years old. It seems to be fine.

ANYWAY, My son and I decided to take it for it's maiden voyage to get gas...it's on fumes on both tanks. The engine takes a really long time to warm up, but even warm it has a dead spot in the first part of the throttle. If I can get past that it seems to rev OK but this is an automatic so that's not really doable driving. So it stalls constantly. We aborted about 1000' out because the steering was super sloppy and I hadn't done more than a simple visual on it. It became very tricky when I had to turn around and go up hill. I couldn't accelerate without it stalling. It's idling was high enough that I was able to crawl home with just that.

So long story short; brakes seem good, steering is super loose (30 degrees of nothing between left and right) and the steering wheel is at 90 degrees (hopefully the last owner just installed it that way.

But none of that matters if the engine can't reliably idle or rev so that's my focus for now.

The stock carb and air-cleaner is what I have (for a 350, quadra jet I think they call it). I've been advised to get an Edlebrock AVS2 but I'd like to hear what others recommend. Is there a good carb/aircleaner combo that can bolt right on to stock? I've never dealt with carbs on a car.

I have not changed the plugs, checked compression, checked the timing or really done any engine work at all. I just checked the oil which looked good (the previous guy said he changed it). It was running (sorta) so I didn't want to mess with it. It sounds like all cylinders are firing but I could be wrong.

Or should I try to get the quadrajet working?
 

fast 99

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Before thinking about buying parts some diagnosis first. Check over the tune up, good plugs not fouled, timing, both advances, inspect wires, cap, ect. Check fuel pressure and volume. If possible check vacuum.

If it does have a q jet with appreciable age likely float is heavy and needs o haul. Some will disagree but the original q jet is the best compromise for economy and driveability on a GM. If you are intent on replacing the carb keep in mind they are generic and may require jet changes or other adjustments. Eldebrock/Carters are decent carbs and can be made to work fine. Just they aren't as bolt on as people assume.
 

EvilGenius

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I went with a different carb for my 350. After some research I decided to go with a summit carb that is a clone of an old holley. It was around $400 and worked great out of the box. I went with it over the standard holley and edelbrock options due to price and I personally don't like the holley front/rear bowl design that leaks everywhere if you want to make a jet change.

Here it is if you decide to look into a replacement https://www.summitracing.com/parts/sum-m08600vs
 

Ricko1966

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My take on Quadrajet vs. Other carbs. There are dozens if not hundreds of variations of quadrajets, changes were made to tailor them to the engine combination they go on. The standard go to replacement carbs have a very generic base tune,Qjet there will be a different model for standard tran vs. Automatic. Not so with the generic replacements. I'd rebuild or have rebuilt my original or correct number Qjet. One that was designed by people way smarter than us to run,winter,summer,start hot,start cold,decent mpg,not foul plugs. The whole package. There's a reason GM didn't use a one size fits all carbureator,and cost savings wasn't the reason. No matter what carb you go with,checking compression and making sure ignition works correctly is first. Lots of good carbs get blamed for bad advance mechanisms etc.
 

Chris64

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Great tips. While I really like the idea of buying a new thing that will just make everything better...nothing works that way.

I guess I need to buy some tools (compression test & timing light). The sparkplugs and wires are another challenge. The only thing the previous owner did "upgrade" was the headers which do a two-one thing. They run straight out from the engine which makes them dangerously close to all the plug wires. He wrapped one of the headers in that heat wrap stuff but not the other and he put little heat shield covers on the plugs and wires. It should probably all be redone and I wonder if it would be worth getting different headers that follow a more stock routing. Removing these headers may be another nightmare based on the rust.

Strange question; I needed to work on/replace the front fenders and inner wheel covers and hood. Is it reasonable to remove this stuff to work on the engine? So far working in the engine bay is a real PITA because how high it is.
 

77Dmax

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You probably have a vacuum leak somewhere.
 

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