[ImpalaGuy]

Originally Posted by Fast305

Why are you worried about going below 17 psi? Assuming you stll have the stock 61 lb/hr 350 injectors, you should be worried about getting it up around 25 psi and tuning it from there.

The injectors are 80lb/hr so it idled bad at higher fuel pressure. So far it has enough fuel at WOT at 17psi so I'm hoping to keep it there just b/c the fuel tables looking good and I don't want to redo them.

Originally Posted by Fast305

The hesitation is lack of tuning in the AE department as well as the increased throttle body size and plenum volume in your intake. The requirements are drastically different from the stock sized TBI and the tiny heated plenum of the stock intake. I bet DE is just as bad with possible surging on deceleration.

Yes I think it's the 50mm throttle body and the bigger intake. I remember when I put a 58mm TB in my LT1 and it was a bear to get right. We're messing with the AE vs. TPS and MAP tables but so far the changes are hard to detect. I may come back and ask you for ideas on this if it doesn't start to converge soon.

Deceleration seems okay but since it's an automatic there's not much there.

Originally Posted by Fast305

Idling poorly in open loop is a sign that the VE tables or the timing is off.

The open loop problem is idling as well as lots of popping/missing/spitting under accel or cruise. The strange thing is that it goes away almost instantly when it goes into closed loop, much faster than the O2 could make changes to the long term fuel trim. The fuel tables look really good above 1200 rpm but under that the datamaster data isn't consistent, perhaps because of the overlap of the cam?

Thanks for the thoughts -- I always appreciate help. I just got another spin from Brian... need to make a quite trip around the backroads to see how it does.