I just put my turbo 434 abc on the dyno. The car ran fine at idle and spinning the rollers through the gears at low rpm. If I floorboarded the car it had a slight stumble then it pulled just fine. If I rolled into the throttle the car would run fine until about 4500 and part throttle then it would act like someone turned the ignition off. If I let off the throttle the car would cone back to life at about 2500. My tps is at 24 degrees at idle and 73 degrees at wot. Would this cause those symptoms?

 

Sounds like something in the Fuel or Timing map. Are you running Alpha N or Speed Density.

The tps will not cause this. Are you having a problem with the RPM pickup at hi load? This will also do this.

 

I'm using speed density. The car runs fine at wot. It's only part throttle that the car completely loses power. It acts like it totally loses spark and just dies. If I go to wot off of idle it runs great and pulls all the way to the rev limiter. It only happens at part throttle. It has me and the guy helping me tune it baffled.

 

Acutal A/F in this area? What is the target A/F there? What kind of dyno? Can you hold it there? Are you running in closed loop?

 

We were shooting for around 12:1 at part throttle and we were actually between 11.5: and 12:1. The car will die if I hold the throttle at the position the motor conks out. The dyno is a Dynojet. We were running in open loop.

 

You should be running in closed loop especially since you are soo rich. 11.5 is way too rich or part throttle and could be the cause of the engine not being happy. Even 12:1 at part throttle is too rich, look at 13:1 or even leaner if your at part throttle.

 

I'll give it a try next time I get a chance to work on the car and give an update. Thanks.

 

does the car have a crank trigger?