misfire

[ddettloff]

So I pulled the 318 out of my wrecked cuda and put it into another 67 notch.
The problem I am having is ther same about 2000 to 3500 rpm the motor misfires.
Timimg set at 12* btdc vac advance working everything related to electrical system is replaced except distributior.
No missing on low end just mid range. running a hei system.
mods include ported heads headers alumiumn intake eldebrock carb.
now at a total loss with this any advice .

 

[tekslk]

Possibly a bad wire, I would also check the gap on your reluckter inside distributor should be 8-10 thous spin it because sometimes they run uneven.

 

[ddettloff]

checked the dist gap it is at 8 checked and replaced all wires did ohm check on new wires and all are fine.

 

[tekslk]

Pull your ecu off and make sure it has good ground.

 

[ddettloff]

ecu has clean ground and is new also it has groung wire direct to battery

 

[dartman1965]

Could be coil breaking down or ozone build up in the cap.

 

[ddettloff]

replaced coil with new accell same results as before.

 

[jimjimjimmy]

may be a bad relucter thats usually what they act like when they take a dump

 

[ddettloff]

Is there a way to test distributor to see if this could be the problem

 

[KitCarlson]

A scope can be used to look at the pickup signal and the coil primary. If that is not available, use a clamp on timing light and move it to each plug wire. The clamp couples via induction, so no spark current, no blink. Spark could be jumping to ground before plug to, so not foolproof.

Since ignition changes have not seemed to fix the issue, it might be fuel, or mechanical, might be valve related.

 

[70aarcuda]

may be a bad relucter thats usually what they act like when they take a dump

bad pickup coil..you an ohm test the pickup coil.....

 

[the wall]

if it has a electronic tach disconnect the lead to the tach and try it ive had the tach cause rpm related miss fire