Flutter on acceleration?

[Hollywood]

Stock twins on 1994.

 

After about 3-4K Rpm, and under 1/4 to 1/2 throttle pressure I get a fluttering sound. I still hear the whine of the turbo increasing simultaneously.

As I move through each gear, this flutter sound doesn't kick in until later in the rpm range.

This does not happen when I left off/close throttle.

 

I'm thinking it's a pressure leak somewhere when the motor is under enough load/stress?

 

The flutter itself is like a headgasket that's on it's last legs or blown. It has a fast 'stiga stiga stiga' sound.

 

 

Holly