All,

I'm working on a 89 Mini with a SRT-4 engine using a Dizzy and a STG 5 HYbrid SMEC from FWD Performance.

The Van came in with a major missfire on all 4 cyls after part throttle when going into open loop. The Van will only run decent with the boost set to 10psi.

I have replaced - New plugs gapped to 28, new Blaster 3 coil, new 3 bar Map, Cap/Rotor, coil wire and a HEP. Has newer 7mm plug wires(?) All the vacuum lines have been replaced or re-secured. NO CODES.

Fuel Pressure gage show good pressure and maintains pressure for hours after running. Set @ 50 psi. Currently has a 10.5 AFR @ WOT/10 psi of Boost.

I cleaned up some wiring issues. Dizzy is set correctly I believe per the marks placed on it by the engine builder.

It starts and runs great. The problem reminds me of spark blow out or rev limiter. When it first came in I played with the tune and could get it to run at 18 psi but with a unsteady AFR. After tuning the engine with the new components now 10 psi is the max.

Any thoughts? The SMEC appears fine, have not monkied with the Walbro but it appears to be fine also. What am I missing?

Thanks,

Marion