Super Jet 91 Superjet top end thoughts?

[Hexum]

I've got a 91 superjet that the rear cylinder seized up on last summer. Had the ski about 7 years and it's run great til then.

Basically stock ski, but is pretty clean. Has a red riva pipe, vortex flame arrestor, rejetted the carb, primer kit and a new scoop and impeller.

Only really used recreational on an inland lake but it has had a lot of use.

I know i'll probably buy a better ski in the future that i can mess with more when i have the $$$ but i want to keep this ski. I'm thinking i'm gonna go and make a sleeper ski with groupk. Have them bore the stock 6m6 cylinders to 701 and port them out, mill/mod the head, mod the intake manifold...

I feel like i've read every post on this site and i know similar situations covered this before... Most would probably say just buy a used 701 to put in it since it'll be about the same price. But i'm thinking it'll run pretty nice with this sleeper kit and i can always let my girlfriend have it when i decide to upgrade later.


I've never posted but i wanted to throw my situation out there to get some opinions. Any comment is appreciated.

 

[crazy4sand]

do that or find a 61x cylinder and have ur cases machined ( or do it your self) to have a 701 .. aslong as ur crank is good

or look on craigslist and find a 701 couch doaner ski for less than what groupe K will charge

 

[aramis]

First thing to do is find out why it seized, and make sure you've remedied that. Then, I'd get a 61x cylinder and use that as already recommended...since it can always be used if you want to later get a set of 62t cases for that ski, etc.

I'm pretty sure you can get a stock 61x take-off top end with pistons for a heck of a lot cheaper than having any place bore and port the 6m6 cylinders...even when the case clearancing is added in.

 

[SuperN8]

I have a slightly ported 6m6 that you could buy from me (minus b-pipe and intake manifold) newer top end and runs Great!!!
Just let me know…
JJC568 has more information on the motor if interested

 

[N3vrSat1sfied]

I have a slightly ported 6m6 that you could buy from me (minus b-pipe and intake manifold) newer top end and runs Great!!!
Just let me know…
JJC568 has more information on the motor if interested

Motor only has 3 rides on in, top end was ported by Savannah Scott. (nate you dont need intake manifold) so Minus Bpipe and carb.

 

[js/sj]

http://www.x-h2o.com/threads/108722-FS-61x-61x-701

 

[Hexum]

Thanks for the info. That 61x 701 seems like a sweet deal compared to sending it to group k. I was mainly considering the sleeper mod and boring my 6m6 cylinder because a friend has some 6m6 cases and a crankcase for me that he doesn't need. I must of had an air leak that seized mine as some of the gaskets didn't look to good.
View attachment 175957


I have read that port work can cause the red riva i have to shake more and snap studs. The pipe always ran well with my engine before and never loosened, but it wouldn't be fun to spend so much on a sleeper mod and have issues with the pipe shaken loose. Don't really want to spend the $ on a better pipe yet.

I don't think that my red riva pipe will attach to the protec head on that engine tho. Anyone know if that's possible?