Which impeller for Challenger 787 110hp: Skat trak 16/21 or 17.5/22.5?

[SeaMe]

I have conflicting recommendations.

I have a 1996 mint 787 Challenger I just bought that I am looking for the best bang for the buck out of. As a reference it tested at 169 and 166 for a compression test.

I want to replace all the seals, carbon ring, wear ring etc and while I am at it put in a performance impeller, pipe etc... whatever I can do within reason to make it the best it can be for what it is.

I have narrowed it down to the Skat Trak Swirl line but some say to get the 16/21 and others say to get the 17.5 / 22.5?


Can anyone comment having used both and briefly describe the differences?

I want to go as fast as it will go with "everday" mods , I wan to know what I should expect for a top speed ( me 200 lbs) by myself and for fun pull a tube once in a while.


Can anyone comment on this?

I would appreciate any information you care to offer,

Thanks

TJ

 

[LouDoo]

Hi and welcome to the SeaDoo forum. It would be helpful to give us at least a region of the US, where you live. Generally an impeller change doesn't give you much bang for the buck, you'll get maybe 1 or 2 mph extra top end.

BTW 166/169 psi is a bit high, ideally compression should be around 150 psi for a 787.

Lou

 

[SeaMe]

Well then my gauge might be off or the motor is worked over. I have videos and pics of the gauge..

I live in the Northeast, but what you say flies in the face of everything I have read from accounts of people using them? I am not looking for 15mph... I want to maximize holeshot and topend with a balance. I have read the swirl 14.5 / 22.5 is the way to go, but then again I heard the 16 / 21 is a faster impeller? All this info from mods here and abroad wrong?

 

[Coastiejoe]

The proper Skat will normally help you on both ends and some increased over-all performance in between due to how the blades are designed. But Lou is right on the money that in most cases, your gain will be minimal. It is almost impossible to gain hole shot and not suffer top end speed. Just as it is almost impossible to gain on the top end and not suffer in the hole shots.

 

[Waterluvr]

The factory 17/22 stock blade for the 1997 Challenger has no equal even with all the offerings Skat has, hard to believe I know. I have the Skats available to loan to people that need to get that out of their system, you're going to lose top end or give up some hole shot either way if you get away from the '97's stock impeller it outshines every one of them.

The one and only *improvement* that you can add to the boat is Skat's 16/24 blade, and you have to limit the passenger load to under 350 pounds at the very most and the pump, engine and drivetrain have to be 100% with good alignment for it to shine. It won't pull a skier but tubes work with it and you'll see impressive top end speeds but the hole shot is really lacking if you carry more than two adults ever you won't like it.

Your best bet for performance is the 97 Challenger impeller, BRP got that one right compared to the previous model year in '96 that part number is #204160027.

 

[LouDoo]

I think this is not the forum for you, your original post was moderated, now I see why. Good luck with your boat and your future endeavors.

Lou

 

[Coastiejoe]

Good call Lou.


Sent from my iPhone using Tapatalk

 

[Seadoobuddy]

I think this is not the forum for you, your original post was moderated, now I see why. Good luck with your boat and your future endeavors.
Lou

Sorry if I'm asking silly questions but........
OK, I see that the OP was banned.
Lou, what did you mean by his first post "was moderated"?
Was it edited by a moderator?