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Carburetor wizard part 2

A LEAN Mixture will burn your eyes

And you mentioned a flutter at cruise

Like a surge in and out

Lean

What metering rods and jets in your Edelbrock 1406 now

Thanks! So the 1406 is stock out of the box. Just going by their specs until I take it apart:
Metering Rods: .073 x .047 in
Primary Jet: 0.098
Secondary Jet: 0.095

I've included a pic of the #1 plug. The rest are very similar.

It is a stock 70 383 block with 440 Source Aluminum Sleath heads (2012 variety and no cracks that I can tell), Edelbrock DP4B intake, the cam info is below:
Thanks again!

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A couple of corrections reqd.
[1] A lean mixture will burn your eyes. No it won't. Unburned fuel is what burns the eyes & this is commonly associated with cams having a lot of overlap. The mixture is contaminated with exh gas at lower speeds & doesn't fully combust. You are smelling unburnt fuel exiting the exh pipe.
[2] Rich cruise mixture can be caused by insufficient cruise timing. Often caused by the vac adv not working or has been disconnected. Cruise timing is usually in the 45-50* range but can be as high as 60* with a low compression engine with a 'hot' cam. With less than optimum timing, the engine is inefficient, requires more throttle opening. With optimum timing, less throttle opening is reqd & engine requires less fuel.
 
1406 - Electric choke

Confirm your electric choke is opening all the way once warmed up , at cruise

Total Timing is off



What Champion number plug s are you running

I check all float levels on Edelbrock Carbs before bolting up - Even new out of the box
 
Agree float level should be checked.
On every carb, not just Edel.
Every Edel carb I have checked, the f/level was out. Could be because of the long distance for the carb to get here, carb gets bounced around, not sure.
 
1406 - Electric choke

Confirm your electric choke is opening all the way once warmed up , at cruise

Total Timing is off



What Champion number plug s are you running

I check all float levels on Edelbrock Carbs before bolting up - Even new out of the box
Choke is opening very quickly. I'll check the floats, etc soon.
 
A couple of corrections reqd.
[1] A lean mixture will burn your eyes. No it won't. Unburned fuel is what burns the eyes & this is commonly associated with cams having a lot of overlap. The mixture is contaminated with exh gas at lower speeds & doesn't fully combust. You are smelling unburnt fuel exiting the exh pipe.
[2] Rich cruise mixture can be caused by insufficient cruise timing. Often caused by the vac adv not working or has been disconnected. Cruise timing is usually in the 45-50* range but can be as high as 60* with a low compression engine with a 'hot' cam. With less than optimum timing, the engine is inefficient, requires more throttle opening. With optimum timing, less throttle opening is reqd & engine requires less fuel.
Makes sense about large overlap cams. So even with a "perfect" tune, I'm just going to have a fair amount of unburned fuel at idle due to overlap. That does make sense.
I will check total timing again. Thanks!
I didn't really think that the cam profile was that far from a 70 383 Cam. More to look at. Thanks again!
 
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