misfire @ cruising speeds MSD digital E curve dist.

[rabiddawg]

car runs great at idle or full throttle
but cruising at hiway speeds it misfires (kinda like spark scatter)
low backfire in the exhaust aswell.
but if I step into it the motor seems to run pretty good?
I have the digital e curve set up using a MSD6AL aswell.
both got good power from battery.
hooked to the + post on battery.
grounds are both on the valve cover hold down.
btw aluminum heads and intake.
engine grounded to frame and battery -.
ground wire also between the engine block and valve cover hold down where the msd 6AL and digital e curve distributor are grounded.
Seems im not the only one with this issue
I talked to a guy at a carshow and noticed he had same problem with his digital e curve dist

[rabiddawg]

bump

[rabiddawg]

geez surely with 33 views someone might have a clue?

[hammertime]

car runs great at idle or full throttle
but cruising at hiway speeds it misfires (kinda like spark scatter)
low backfire in the exhaust aswell.
but if I step into it the motor seems to run pretty good?
I have the digital e curve set up using a MSD6AL aswell.
both got good power from battery.
hooked to the + post on battery.
grounds are both on the valve cover hold down.
btw aluminum heads and intake.
engine grounded to frame and battery -.
ground wire also between the engine block and valve cover hold down where the msd 6AL and digital e curve distributor are grounded.
Seems im not the only one with this issue
I talked to a guy at a carshow and noticed he had same problem with his digital e curve dist

I will take a stab at just something I see when reading what you posted. Keep in mind I do not or have never used a E Curve Dist.

grounds are both on the valve cover hold down.
ground wire also between the engine block and valve cover hold down

Could be wrong here but try running the ground straight to the chassis, better safe then sorry for sure, a ground issue can cause all kinds of issues.

[lively]

IF YOU HAVE ANY/ ANY/ANY CORROSION BETWEEN THE HOLD DOWN BRACKETS AND THE OTHER GROUND WIRE TO THE BLOCK YOU ARE NOT DOING IT ANY GOOD

UNLIKE METALS WILL CAUSE PROBLEMS AT TIMES[ALUMINUM AND CAST IRON!!]
RUN THE GROUND STRAIGHT TO THE FRAME AND TRY THAT 8) 8)
LIVELY

[rabiddawg]

I think I found the problem
stripped out negative battery terminal connection
(it was barely on)