670 Mods?? 740??

[670Xpower]

I have a 99 summitX 670. 151X2.5 track 20 44 gears. I need more power Has anyone had good luck or info i a 740 big bore kit? Or should i just bore it .10 or .20 over and do more mods? I also want to put a real aggressive rotory valve. I ride 6500 ft and higher its a hill shooter Any info will be great. Thanks

 

[sledsrock]

Boring it .010 or .020 won't get you much. Now a 740 with all the bells and whistles can be a good runner. How was room made for the 2.5 lug track?

Give Big John a call regarding the 740, he has all the in/outs on those things.

Sled Head Racing (612)-718-3861

 

[670Xpower]

It maybe a 2.4 but i rolled the chain case and moved the swing arm and thank you i'll give him a call

 

[doomama800]

I had a 98 670 summit I took and had head shaved, port and polished cylinders, with a single pipe on it. That sled ripped, cost me 450 bucks for the engine work the pipe was thrown in with it when I bought the sled cause dealer took the stock one to put on something else. They had to drill out the baffles in the air box to get enough air in it to run right. My skidoo dealer did all the work for me.

 

[CBX]

740 rotary valves rock. If ya don't mind thowing that amount at an s chassis then do it. They run very well.

Precision Performance is the one i've ridden.