ISO parts and 550/701 swap questions

[Rider701]

I’m a newbie at building skis and probably wasn’t the best idea to start from scratch but I have a few questions and ISO some parts for my ‘87 JS550 701 swap build

The 701 62t/62t I bought is bored 2mm over and I am looking to get a little more power out of it. I have the octagon-looking riva non girdled head that I believe to not be made anymore (can post pics if necessary) on 38cc 760 domes. What compression would i get with those size domes? If I need to get new domes, where do I get them from since on Rivas website there are only ada domes? <<are riva and ada the same domes? *note: they are locking domes*
How do I lighten the stock 701 flywheel?Kawi 650 performance exhaust worth it?
Best fuel tank to use? Custom fuel tank? I’d like to get 45+ min of ride time.
What are some must-haves for a 550 and/or 550/701 ski?
Side and front braces for a flat water ski?
Should I relocate the exhaust to the bottom starboard side? Currently at the top port side aka donkey d*ck exhaust

ISO these parts:
701 stock exhaust
Kawi 650 performance exhaust
701 FP manifold
701 electronics
550 aftermarket intake grate
550 aftermarket ride plate (preferably something that will handle very well and not let the ski porpoise but will still let the ski hit jumps and slide a little - prowatercraft?)
550 front fuel filler
Oem superjet throttle lever
Yamaha start/stop switch button
(4) Rhaas 701 motor mounts (for another ski)
Js550 quick steer plate
Prowatercraft front sponsons
OCD solutions bilge switch
AM chin pad cover
Sea doo xp water box
701 coupler cover
Superjet bilge bracket
Js550 bilge bracket


Should I make this a full build posting ?

 

[mikidymac]

The 62T cylinder isn't the best for a standup as the porting is for top-end. If it is what you have then you can run it but it's not going to give you the hit you are looking for without having it ported by someone that knows exactly what they are doing.
Why are you using a 760 head on a 701 cylinder? You need to have the correct domes for the cylinder.
Yes you can have the stock flywheel lightened.
Probably going to want a 20 impeller.
The stock fuel tank is going to be your best bet for runtime. The flywheel cover from the 62T/62T isn't going to work because the oil pump boss will hit the fuel tank.
You must buy the Rhaas Conversion kit to put the 701 in a 550.
Side braces should be added.

There are a bunch of step by step conversion builds on PWCToday.

 

[Rider701]

The 62T cylinder isn't the best for a standup as the porting is for top-end. If it is what you have then you can run it but it's not going to give you the hit you are looking for without having it ported by someone that knows exactly what they are doing.
Why are you using a 760 head on a 701 cylinder? You need to have the correct domes for the cylinder.
Yes you can have the stock flywheel lightened.
Probably going to want a 20 impeller.
The stock fuel tank is going to be your best bet for runtime. The flywheel cover from the 62T/62T isn't going to work because the oil pump boss will hit the fuel tank.
You must buy the Rhaas Conversion kit to put the 701 in a 550.
Side braces should be added.

There are a bunch of step by step conversion builds on PWCToday.

I’m taking the head off my other ski and it would be easier not to buy/sell any parts because Ive heard 760 domes will work on a 701. Cylinder has mild porting and Ive already ordered the conversion kit. Thanks for the info

 

[bored&stroked]

-62t porting is less top end bias then 760's, I'd call it a mid range porting. Nothing wrong with it at all.
-83mm bore can probably run 84mm bore domes but I've read 81mm domes is a better choice, not sure why. Look at ada's website for compression rations, and whatever it says for a 760 with 38cc domes just lower that number since your cramming less CC's into the same space.
-kawi 650 pipes are not worth it over stock unless you get a factory pipe. Otherwise just mod the oem pipe if thats what you want to use exhaust wise

A lot of work to put in a 550 hull. Never understood people who do this but good luck.