Car has just started doing this. plugs are new, wires are new, dist. cap looks ok, coil is new. Only thing that someone has mentioned is the ignition box.

Plugs, AR133s
Wires, MSD 8mm
Coil, MSD Blaster SS
Ignition box, Crane Hi 6

Setup,
383 10:5:1
Iron Heads
Stealth Ram with 950ecm

it doesnt feel like its blowing the spark out. It acts like its hitting a rev limiter at 5500. It did it then i replaced the plugs, and played with the timing with the dist a bit and i thought it went away then the other night it was doing it again. Any thoughts would help me in figuring out why the car is doing this. Ran fine all of last year.

 

Sounds to me like one of three things. The first, I'd check your cap and rotor on the distributor. If the bushing that goes "through" the rotor went bad, that could cause the problem as the spark isn't going through properly. Second, depending on your cam and what springs you put in, you could be hitting valve float though if you are experienced builder that's probably not the case. The third thing I can think of would be your timing not being right...but you said you adjusted that already though maybe your distributer isn't staying locked down, thus your timing is moving a bit?

Have you checked to see if your plug wires are grounding out on your headers?

 

thanks, ill try playing with the timing some more. im pretty sure the wires are not grounding out on the heads, i had an experienced builder put my motor together. i can easily rule out the box if i bypass it, but ill try the timing thing first and see what happens.