Could my msd 6AL box be the problem????

[ballajb64]

I have a 1991 H.O motor with aluminum heads, longtube headers, F303 cam, typhoon upper and lower intake, and msd (dizzy,coil,6AL box) and 5speed transmission. For some reason i can not go past 3500 rpms, what could be the cause of this and what can I do to fix this problem? I just replaced my fuel regulator because a few people said i might not be getting the right pressure, so i changed it to a holley adjustable one and the problem is still there... So now i am wondering if it is more of a ign problem. So now i am wondering if it could be my msd box what do you think?

 

[stang9150]

what happens at 3500,does it start breaking up and missing?when was the last time the car ran decent?Any changes made after that?Most the msd boxes i have seen on stangs are plug and play into the stock ignition,did you unplug the msd and plug the stock ignition plug back in the coil?Did you put the 3500 or 4000 rpm rev limiter in the msd by accident?Could be a coil going bad.Those are just some thoughts of things to try and look at also check your base timing.

 

[ballajb64]

yea i see i need to recheck some things.I have a msd coil that does not have the slot for the harness. I did a efi swap in a 64 1/2 mustang so things are a little different. But i am going to check out the box to make sure there isnt a small chip in it

 

[HISSIN50]

Pull codes.

Be sure you're running copper plugs.

Bypass the box.

If it still happens, have the TFI module tested at the parts store and/or swap in a spare ignition coil if you have one.

Good luck.

 

[ballajb64]

ok thanks, i will try that