Baja 164 SS with 1982 Mariner 115 setup?

As the title states I have a 1983 Baja 164 SS with a 1982 Mariner 115 ELPT (Serial#: 6127590). The cavitation plate is level with the pad and I'm turning a Quicksilver Black Diamond 3 blade aluminum prop, 12.75" x 21". The carbs are synced, at WOT the carbs are wide open (carb vanes are perpendicular to the venturis). Trimmed out, I'm turning 5500rpm for a gps indicated speed of 53mph +/- .5mph. If I trim any more I can rev higher but lose speed.

I was looking at switching to either a Quicksilver Lightspeed 3 blade stainless, 13.5" x 20", a Michigan Wheel Ballistic 3 blade stainless, 13.125" x 21", or a Michigan Wheel Ballistic 3 blade stainless, 13.375" x 19".


Questions:

Am I running the right size prop?

Would switching to the same size, or a different size, stainless prop affect performance in anyway?

Would a jack plate do anything for performance?

Would a different style (chopper, cleaver, labbed, etc) prop make any difference?


I realize without actually trying anything of these things it's hard to say what will work and what won't. I'm just looking for a starting point if any, or if I should just leave it alone and enjoy it for what it is?

Ultimately what I'm after is more top end if there's any to be had.


Thanks

6" jackplate with 20P laser II prop should do it. Prop shaft about 2" below the pad.

Ballistic will work good without a jackplate but not good at all with a jackplate. They like to be run deep.

Thank you.

If I go with the Ballistic, should I run a 19" or 21"?

If I go with a jackplate, will I need a nose cone kit?

You won't need a nosecone. I've got a 16' Baja with a 115 Etec, before that it had a 100 crossflow. 4" manual plate, runs well with the propshaft maybe 3" below the pad. It's not that sensitive to engine height and I've got lots of water pressure. 55.7 with the crossflow, 23 SRX, 62 with the Etec, 24 Laser.

Thanks, good to know.