Port engine loses power at 2800

[Grande]

Hi all I have 28bert with twin 260’s
Port side has had some electrical issues and I thought they were resolved looking for new places to trouble shoot. When I try and get on plane the port engine is fine until 2800 rpm then as I advance throttle the rpms fall off if I pull back. Then they come back.

So far replaced distributor coil electronic ignition all msd Boat ran great then started having issues then New plugs wires fuel filter at carb ,water separator fuel pump.
Same issue starboard motor runs fine any ideas where to look
Thanks

[bob lico]

assuming you have MSD 6A lets start with this. i am not a parts changer!

[Bruce]

Are you running mechanical or vacuum or both timing advance. What's your base timing number and advance number at 3400 in neutral.

Is the MSD a ready to run or are you using a 6a or 6al ignition box lIke Bob mentioned.

If your running the 6al (l stands for rev limiter) the Rev limiter can be set as low as 2000 rpm. Has yours been set?

[kross1]

Hello All
If we are not positive it is electrical I would also look into the fuel system. Pickup line. Filter, pump, screen in carb.

[Grande]

Correction it is a petronix flame thrower igniter distributor and matching flamer thrower coil
There is no external ignition box


All filters have been replaced as well as fuel pump
I will check timing last time was set at idle with vacuum gauge
Thanks I will update with more info Monday