94 Chevrolet Missing at mid to high rpms..

[ridnlow]

Truck was missing yesterday at take off so my dad and i replaced the distributor and rotor.. Now it is missing at mid to high rpms.. we have a msd ignition and cheap plug wires.. do you think we need better plug wires???

[The SPEEDY]

Might as well replace them. I always start with what I think the problem is, and go from there

[99-2door]

Check your timing on the distributor. On a TBI engine the ECM can compensate for up to 7 degrees off. I worked on a 95 a few days ago that idled well but performed poorly at mid-high RPMs. Turns out the timing was 21 degrees off, The computer was able to make the engine run well at idle, but not at higher speeds. As soon as the timing was dialed in the engine ran great all the way across.