Mild Built 340 Timing/tuning help?

[Dale Davies]

No ****. But what happens when you change just the main jet? Get it?

In a Holley, changing the MJ changes cruise A/F with a very small affect on the power

No ****. But what happens when you change just the main jet? Get it?

In a Holley the MJ changes the cruise mixture and also affects the power mixture by how much cruise was changed.
In the Rochester and Carter/Edelbrock carbs, just changing the MJ changes both cruise and full throttle A/F ratio. Normally when tuning these metering rod carbs both the jet and metering rod are changed. Once it is tuned you can swap metering rods for tuning for weayher or altitude. Normally do not have to pull the cover off the top.

 

[Rat Bastid]

In a Holley, changing the MJ changes cruise A/F with a very small affect on the power

In a Holley the MJ changes the cruise mixture and also affects the power mixture by how much cruise was changed.
In the Rochester and Carter/Edelbrock carbs, just changing the MJ changes both cruise and full throttle A/F ratio. Normally when tuning these metering rod carbs both the jet and metering rod are changed. Once it is tuned you can swap metering rods for tuning for weayher or altitude. Normally do not have to pull the cover off the top.

Whatever. You’re missing it and STILL getting it wrong.

 

[Dale Davies]

Whatever. You’re missing it and STILL getting it wrong.

Whatever floats your boat.

 

[Swinger 340]

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EDIT: This is our first engine build. If we sound like we're stupid, it's probably because we are! Lol. I continue to learn though.

Nice looking engine compartment, but I would shorten the heater lines and plug wires. If they were to lay on your headers, you will have other problems. They may be off the headers now, but when the engine compartment heats up, they will drop down. I agree on the fuel comments, but I was a little confused on the timing question. I thought you were talking about the dwell, which I set at 32 (dual points).