[PercentSevenC]

As some of you know, I've been getting ready to do a 5-8 PSI blow-through setup with a 45 DCOE and S5 turbo on my streetported R5 13B, and I've got a couple of questions.

First: I have two options as far as which carb to use. The first one is an old-style "made in Italy" 45 DCOE. It looks to have pretty high mileage and the throttle shaft seems like it's a little tweaked, and doesn't close fully without an external throttle return spring. Seems to work okay otherwise. The other carb is a newer "made in Spain" model that seems to be in a little better shape overall, though it's a bit dirty. It also has some weird brown/orange sand-like gunk in the float bowls, which will have to get cleaned out. I have heard the Italian ones are better somehow, but I can't find details as to why. Which one do you guys think I should use? I'll probably use the plastic floats out of the Spanish one either way.

Second: I'm currently having a very choppy cruise at less than about 1/4 throttle. More than that and it's smooth and has decent power. Deceleration is smooth, idle is acceptable. I read one post that suggested that the float levels might not be set right, which is possible since I haven't checked them yet. Any other probable causes? Current settings are listed below:

Main venturi: 40mm
Aux. venturi: 4.5mm
Idle jet: 65F9
Main jet: 180
Emulsion tube: F11
Air corrector: 175
Accel. pump jet: 60

Since I'm still NA, I'm not going to bother trying to get it perfect yet. I'd just like to solve the cruise problem for now and get it tuned for real once I have boost and an air/fuel gauge.