My SN wants to go faster

[Rgerb]

I have a Squarenose with the stock 650 motor, coffman pipe, prop, and prok f/a. I top out at the low to mid 30s and want a bit more all around speed. what should i do next without completely breaking the bank?

 

[cleetus]

whats your compression?? I high compression head will allow you to turn a steeper prop...

 

[Rgerb]

compression for both cylinders is between 140 and 145

 

[SkiDiggity]

it sounds like it is time for a top end rebuild to me

 

[SkiNaked]

You need to get a 701 motor and B pipe.

 

[Rgerb]

what do you mean? put in a 701 top end? how reliable is that

 

[SkiNaked]

How much do you want to spend? How mechanical are you?

 

[Rgerb]

i really cannot afford to put in a new 701 right now. i am pretty good with engines and know a lot of people as well. short term i wouldnt want to spend more than 500 but next summer i should have some more cash

 

[SkiDiggity]

my uncle has a 650 bottom with a 701 top in his blaster and it has the same power as his superjet and it is bullet proof that motor rocks if only we can get the pipe to stop over heating lol.

 

[SkiNaked]

Purchase a used 61X cylinder. Hone it out and put in a piston kit. You can do the minor grinding with a dermal on the cases and get a 701 going for under 500.

 

[SkiDiggity]

i am with skinaked on that one once you do that conversion you will love it the power that motor puts out rules

 

[Rgerb]

ok that sounds good, thanks a lot for the input!

 

[SkiNaked]

No problem. Good luck. Also keep that square. SN superjets rock!!!

 

[Rgerb]

I am definately keeping it, no worries on that. also, where would you buy the piston kit? are you talking about a wiseco kit

 

[SkiNaked]

Check this out. not a bad deal if the cylinder and pistons are in good shape.

http://www.x-h2o.com/threads/58778&highlight=pistons

 

[SkiNaked]

Alantic Jetsports has a good deal on WSM piston kits. Wiesco are best but if you are on a budget you will save with WSM. http://atlanticjetsports.com/wsm_piston_kits_-_yamaha.htm

WSM Performance Complete Top End Piston Kits include; All pistons, rings, wrist pins, circlips, top end gasket kit and top end bearings.

 

[Rgerb]

yea i could definately afford that, then i would need to get a 61x cylinder and have it honed, correct?

 

[SkiNaked]

Depending on the shape of the cylinder. You can hone it out yourself or have any local machine shop do it cheap.

 

[SkiNaked]

Your going to need a head as well. If you can fine a used aftermarket head that would be best to raise the compression some. If not find a used stock head and have it shave down a touch to raise the compression to around 175-180. You do not want to go much higher then that on Pump gas now that there is so much ethanol in it.

 

[Rgerb]

if i got a deal like this should i still get new pistons or just a gasket kit?

http://cgi.ebay.com/ebaymotors/ws/e...290329757201&viewitem=&_trkparms=tab=Watching