slight hesitation any thoughts

[z210]

every time i change gears the car hesitates a little. it's like a little sluggish. not like it wants to stall, but more like it wants to not rev. if i hit the throttle deeper and faster then this hesitation goes away. this all happens when im driving really mellow. the car boosts hard all the way to 7 grand. it's boosting 10 pounds. no bov. the car idles fine and revs well and starts just fine. it's not giving any trouble codes.
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here are the mods.
stock ca18det in my 74 b210
three inch exhaust, with ebay fart can
cold air induction
fmic, 27x7x2.5 with 2 inch intercooler piping
timing is set at stock recommendation
rebuilt turbo
ngk spark plugs
walbro fuel pump

i also have a nismo adjustable fuel pressure regulator that i will be installing this weekend.

i'm clueless as to what could be causing this problem. my piping from the maff to the turbo inlet is a little twisty with some weird bends, could this be causing my problem?

or is it a fuel issue? could it be my secondary butterflies not kicking in fast enough? right now they are set up stock, with all the stock vacuum lines connected as well as the vacuum reservoir. the little solonoid that is next to the vacuum reservoir is not connected. When i did the swap this little solonoid had the wires cut and i dont know where to connect it to. any ideas?

[float_6969]

How far is the MAFS from the turbo inlet? Any weird bends post MAFS shouldn't really cause any problems, but if you've got a bend right in front of the MAFS, that can cause issues.

It honestly kinda sounds like a very minor vac leak. Double check for leaks.

Pull the codes from the ECU and see if you get anything.

If you've got butterflies hooked up as stock, but the solenoid isn't wired up, they're open all the time and not doing anything. The wiring for the solenoid goes into the chassis harness for some reason. Never understood why Nissan did that. There is a writeup about the butterflies in the FAQ that will tell you what pin to wire the solenoid up to on the ECU plug. Remember that the ECU switch's the ground on and off, so the solenoid will have 12V+ supplied to it with the ignition on to one wire, and then the other wire will go to the ECU and the ECU will handle grounding the solenoid when it chooses.

Also, are you in the US? If not, are you sure you've got a JDM ECU? The EDM ECU's don't have any provisions for the butterfly valves.

Last is that it could be ignition related, but it doesn't really sound like it to me, so lets check the other stuff first.

[z210]

it was the dam butterflies not doing anything. last night i switched the line going from the actuator to the line on the little black vacuum canister that has a fat source of vacuum. problem solved. no more hesitation. it now has a ton of low end torque and the power band seems to be a lot more smoother when the boost hits.