Carb question stock 340

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What kind of stall would you put on a stock 340? Also I was looking at 3.73 for gears but I don’t know much at all on the subject
If you don't have overdrive, you won't enjoy 3.73 on the highway. I run 3.23s which aren't terrible at 60-75 MPH, not rodding the guts out of the engine.
3.55s are the best of both worlds, you give up a little on top end with higher engine speeds, but more low end grunt. Mine jumps at low speeds with a throttle tap and its a 318 with. 3.23s. (Healthy 318) Headers and intake will be your most noticeable power gain. You'll enjoy the car so much that eventually you'll pull the engine for a complete redo. Then you get to make all the really fun go fast changes! :)
 
Switching between carbs, by the way things look, the angle of your return spring. You need some serious work on the kickdown linkage. Post a couple pictures of the left side of the carb, the throttle bracket and kickdown linkage. So someone can help you out.
 
That’s all how it was when I bought it but since I copied it to install my new one I took some pics and posted in the fuel and air. Thanks
 
If you are wide open throttle,
and a vacuum gauge says near zero, you're getting close to matching the carb to the engine
 
Having owned a '68 340 for 54 years, I found that Carter/Edelbrock carbs were easier to tune than Holley and similar cars. Metering rods are far easier change that power valves and channel restrictors, and older Carter's have 3 stage metering rods. I ran Holley's but was not impressed with them over the AVS. The Holley carbs always got lower MPG by a lot than the Carter's. I was able to tune a 340 to get 24 MPG during the late '70's energy crisis and a Holley would never perform that well.
And fuel economy is not just paying less for gas. Fuel that is wasted during combustion ends up either washing the cylinders causing wear or ends up in the oil, causing wear and deposits. This is why a modern FI engine lasts longer than an older engine with a carb. They simply have better fuel management.
By far the best compromise is a Thermoquad which has both the air flow for power and small venturis for fuel atomization. Best of both worlds. But it does require more care in assembly but no difference in tuning over an AVS. There are pleanty around but you do need an adaptor for a square bore manifold or an Edelbrock RPM with the spread bore carb mount. This is what I am doing for my restored 340 which hopefully will be fired next month.
 
What kind of stall would you put on a stock 340? Also I was looking at 3.73 for gears but I don’t know much at all on the subject
Leave it alone. People are generous in spending your money.
My advice is spend the money on fixing what needs to be fixed and fuel for tuning.
Then see if you still want more acceleration or top speed or whatever.

Fix the belts if needed. Get the PCV and breatehr connected. Make sure the vapor lines are connected and open. With the after market carbs the bowls only vents into the air cleaner - so that one is simple. That leaves the fuel tank vent and and vapor lines to a charcoal can or something.

Tuning. Since its stock, it ought to be easy, just follow the book.
But with the 4779, there's a decent chance the distributor has been messed with or replaced.
If its factory, unmolested, then do it by the book and see how it goes when you adjust the idle fuel mix. If your satisfied, great. If its stinks, or dies when put in gear, or needs a high idle rpm, then the timing curve needs to be measured.
If its not factory unmolested, then the timing curve needs to be measured.
When you have graphed timing versus rpm, then you will know whether a smog curve with lots of fast advance above idle, or something more normal.
With a more normal curve, try an initial around 12* BTDC at 750 rpm.
With a smog curve, you'll have to compromise and use less initial until you modify the slots.
 
If its not factory unmolested, then the timing curve needs to be measured.
When you have graphed timing versus rpm, then you will know whether a smog curve with lots of fast advance above idle, or something more normal.
With a more normal curve, try an initial around 12* BTDC at 750 rpm.
With a smog curve, you'll have to compromise and use less initial until you modify the slots.
A good example here. Distributor curve help needed
You'll need a timing light, tach, and a golf tee to measure the rpm vs timing.

Another good example here.
 
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