When engine rpm rise up 2800, fuel injectors cut off and rpm come down. If I try hold rpm hi, rpm go up to 2800 then fall down, go up and down and so on. That happen every time.

Rpm never rise more than 2800.

- Pulse Width Modulated – Returnless system

- all handheld dash data looks fine.

- no any errors.

Engine is sbc 350 cid (Boss Hoss 355 hp).

Distributor is Mallory Promaster 8360M.

Coil is Mallory 8207M.

Atomic tach signal is connect to coil -.

Handheld dash setting are check many times, everytihing be correct.

Need help!