Rotax 670 head compatibility q's [Archive] - Snowmobile World : Your #1 Snowmobile Forum

: Rotax 670 head compatibility q's


LabradorBoy
06-26-2002, 06:26 PM
Does anybody know the major differences betqween these two heads? *I believe the 670 twin piper as you can find on a '95 Mach 1 has a higher compression ratio than the single pipe 670 as in a '98 MXZ 670 or even the '99 670 HO.

I'd like to transplant a single-pipe head onto a twin-pipe 670 but I'm not too sure about head geometry, squish, etc.

Any insight would be appreciated.

-Rob

Rocketman
06-26-2002, 09:54 PM
Moved to Skidoo

Are the part numbers different?

HotM1
06-27-2002, 08:07 AM
That head will work on the 95-96 machs if you cut it. 95-96 cylinders are 1mm taller than the single pipe cylinders.So to retain the right squish clearance of .065-.070 skidoo cut the head.

Krusty
06-27-2002, 08:39 PM
Look in swap meet.I have a 95 head.

LabradorBoy
07-15-2002, 01:04 PM
</span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote (HotM1 @ June 27, 2002, 06:07am)</td></tr><tr><td id="QUOTE">That head will work on the 95-96 machs if you cut it. 95-96 cylinders are 1mm taller than the single pipe cylinders.So to retain the right squish clearance of .065-.070 skidoo cut the head.[/b][/quote]
So,

If the twin-piper cylinders are 1mm longer, I can shave ~0.040" from the single-pipe head to have the same squish, correct?

Just want to be sure.