[xjohnx]

Originally Posted by DeliciousTuning

I will need to watch for this while I am on 91 octane. Once again didn't notice this on the 75mm pulley. But will see what it does now on the 70mm pulley.

Originally Posted by CK_Bladesmith

1st gear not really, 2-6 is extremely noticeable if you're trying to accelerate without going into boost. I'm talking maximum fuel economy takeoffs.

I really think it's due to the fact that while not boosting, the air is channeled through such a small hole, and when you give it just enough gas, or not enough, the vacuum/throttle controlled bypass valve kinda freaks out, causing the stuttering.

It's only really severe while cold, but once normal operating temps have been reached it's waaaaay less pronounced.

If you really wanna test it take the car for a highway ride and set the cruise at 75mph. Of your engine isn't totally warmed up it's gonna stutter like crazy IF you, say, climb a slight knoll such as an overpass. While the terrain is flat it's deliciously smooth, bit small hill climbs will trigger it, I think, due to the fact that it needs to boost based on the position of the throttle.

Feather the throttle and you will see. Try not to go Into boost as long as you can and it will pop up.

Bill -

If it helps, this sounds a lot like the issues I was experiencing with the logs i sent you a week or so ago. I haven't followed up since my car has been in the shop getting some hail damage repaired. Should have it back tomorrow.