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Missing at constant speed?

Checked compression on front and rear cylinders. 155psi and 165psi respectively.

Pulled the carb. and checked emulsion tube. Appears to be a stock tube it has the five holes on one side and three on the other. Seems like I remember the Dynojet kit being a completely different configuration of holes. I compared it to the last carb I used and they were the same tubes and the other carb I built back to stock after someone Dynojetted it.

Pulled the carb again and refitted with a known good slide albeit I couldnt find any holes in the existing one. No difference. Seems like the sputter is still evident. I'll know more by mid-week.

I have re-sprayed intake gaskets and ordered new exhaust gaskets just in case but I really dont think they are leaking.

I am still thinking valve train. This all started after camplate, cam, lifter pushrod change. I wonder if a pushrod could flex enough or if a lifter is just giving up?
 
I'll go out on a limb on this. Seems everything has been checked, adjusted or replaced except plug wires......sometimes the simplest things are overlooked.
 
I'll go out on a limb on this. Seems everything has been checked, adjusted or replaced except plug wires......sometimes the simplest things are overlooked.

HMMMM, I got to say I would ohm them both out, and check the screw on cap on the end of the spark plug, I cannot tell you how many i have seen loose, and it will cause more problems than you think:s
 
HMMMM, I got to say I would ohm them both out, and check the screw on cap on the end of the spark plug, I cannot tell you how many i have seen loose, and it will cause more problems than you think:s

Haven't ohmed them out but the screw is tight.

Recommendations on brand of plug wire?

I've definitely thought of plug wires but it would seem to me that it would miss in all throttle ranges....
 
Haven't ohmed them out but the screw is tight.

Recommendations on brand of plug wire?

I've definitely thought of plug wires but it would seem to me that it would miss in all throttle ranges....

Stock are fine, electricity is a funny animal:s I am running the 10 mm SE wires I like em:D
 
Waiting on plug wires to get here. Until then I put new torca clamps on the mufflers and re-gasketed the headers with Cometic C9540's. Re-jetted back to the 46 that should be required for this application. The good news is it runs as if the mixture and jetting is good. HOWEVER, the constant speed sputter is still present! Maybe the plug wires.....I'm hoping anyway.
 
Waiting on plug wires to get here. Until then I put new torca clamps on the mufflers and re-gasketed the headers with Cometic C9540's. Re-jetted back to the 46 that should be required for this application. The good news is it runs as if the mixture and jetting is good. HOWEVER, the constant speed sputter is still present! Maybe the plug wires.....I'm hoping anyway.

OK, I am ready to throw in the towel on fuel. With everything you have done, you should have seen some measureable change that would lead you to a solution. As has been suggested, move on to electrical but change plugs as well; I would try NGK DCPR9E gapped at .040". I would also check battery and ground connections. Stock wires should be fine; have run them on hipo motors with no issues. I don't believe the problem lies in the valve train.:nosad
 
Adding to my previous; too late to edit.:(

Bigger isn't always better when it comes to plug wires on an ion sensing system. If the resistance is out of spec you could have all kinds of ignition gremlins. I have seen detonation issues resolved by replacing the SE wires with stock.:D I would stick with stock wires before introducing another variable component into the diagnostic mix.:s
 
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