Tune up

[nick.rembecki]

I just picked up this car a couple weeks ago. I got all the vacuum leaks taken care of, cracked vacuum caps, tuned the carburetor, replaced fuel pump. Car wants to stall on deceleration after about a 20 minute ride. I’m thinking of changing fuel, oil and spark plugs. I’m looking for suggestions on replacement spark plugs. 73 duster 340. Thanks in advance.

 

[harrisonm]

Beautiful car. Very nice picture from a professional looking angle. I am guessing you are an accomplished photographer.
There was a very similar thread like this last week. I have used Autolite 65 plugs in my 340 for about 25 years. I have a 69 Barracuda with a 340 that has been modified to about 375 HP. It has headers, Eddy Air Gap, Eddy 650 Thunder Series carb, complete MSD setup to include their non-vacuum distributor and plug wires, and a Comp Extreme Energy 260 cam. My car runs great with the Autolite plugs, so why change.

 

[Bewy]

If the engine is stock ort near stock, NGK plugs, 4 heat range.

 

[furrystump]

What carb and how hard of decel?

 

[Dartswinger70]

Autolite 65's...

 

[middleagecrisis]

I always do those things anyway on any new car that I buy just to make sure I’m starting from a clean slate. I don’t think that’s your problem though and I wouldn’t expect doing those things to fix the stall on deceleration. It sounds like a carburetor problem to me.

 

[Bewy]

The FIRST thing you do on a car that stalls on decel is....check the carb float level.

 

[Yellow Duster]

Bewy is spot on!

 

[nick.rembecki]

The FIRST thing you do on a car that stalls on decel is....check the carb float level.

I’m planning on rebuilding the carb

 

[TT5.9mag]

I’m planning on rebuilding the carb

It’s pretty easy to check the float level first and eliminate one variable.