670

[clint/KTM/16]

hey i heard that the best years for the ski-doo 670's are 1995-to-1999 I am wanting to hear your knowledge or your thoughts on this opinion. because I have a 1996 formula ss 670 with a 1999 motor so it seems it'll work out good

 

[Summitric]

The '98-'99 670x(summit) or 670ho(mxz) are the power mongers... They are rave valve, and pumped up compression and special rotary valve timing....... Most other 670's are base line...regular 670 is about 125hp and the 670x and ho are about 140hp stock

 

[dooryder]

so if its that much stock, how much is your thunder bunny putting out for HP#

 

[Modman]

The '98-'99 670x(summit) or 670ho(mxz) are the power mongers... They are rave valve, and pumped up compression and special rotary valve timing....... Most other 670's are base line...regular 670 is about 125hp and the 670x and ho are about 140hp stock

Are the timing curves different? I thought they were due to the added compression of the HO/X motor. Its been a while though so my memory is a little foggy on that.

 

[boondockin]

hey i heard that the best years for the ski-doo 670's are 1995-to-1999 I am wanting to hear your knowledge or your thoughts on this opinion. because I have a 1996 formula ss 670 with a 1999 motor so it seems it'll work out good

The 670 is a great sled to learn on, i had a 95 with some parts off a 96, the best thing i did was put the skid off the 96 on it with the two inch paddle track and it turned it into a awesome sled and i swapped out the steel skis to some from a sno pro cat, but now i've upgraded, it got small quick for me anywho, my brother has a 99 summit x that would stroke mine till this year :d

 

[Haggis]

The '98-'99 670x(summit) or 670ho(mxz) are the power mongers... They are rave valve, and pumped up compression and special rotary valve timing....... Most other 670's are base line...regular 670 is about 125hp and the 670x and ho are about 140hp stock

You sure about 670x making 140hp - that seems high - are you talking with pipes???

 

[Summitric]

you sure about 670x making 140hp - that seems high - are you talking with pipes???

i'll have to check my books, but i thought the x was makin' 138 stock form?? I could be wrong..... I know the regular 670 was 13hp less than the x or ho engines

 

[brew_doo]

i'll have to check my books, but i thought the x was makin' 138 stock form?? I could be wrong..... I know the regular 670 was 13hp less than the x or ho engines

I remember 134 as the hp # Ric. I had a 98, great sled back in the day.

 

[Haggis]

Please doo - I am curious now. I know that motor worked well but 120 ish sounds more like it doesn't it?

 

[Summitric]

The regular 670 was rated at 115hp and the 670x or 670ho had 128hp .....

 

[dooryder]

how much does your mod put out ric?

 

[Summitric]

how much does your mod put out ric?

it was dynoed and the dyno broke and his last reading before it broke was over 150hp... Have done more since then, however, and now will be dooin' even more when i have the time....

 

[sledobsessed]

it was dynoed and the dyno broke and his last reading before it broke was over 150hp... Have done more since then, however, and now will be dooin' even more when i have the time....

what do you have done ric? and what else you doin pics would be nice to

 

[4extreme]

The 670 is a great sled to learn on, i had a 95 with some parts off a 96, the best thing i did was put the skid off the 96 on it with the two inch paddle track and it turned it into a awesome sled and i swapped out the steel skis to some from a sno pro cat, but now i've upgraded, it got small quick for me anywho, my brother has a 99 summit x that would stroke mine till this year :d

Are you sure that isn`t my old `95 670? It almost the same things I did. The other thing I did was lift the front of the sled because it plowed too much in deep snow. My 670 was rated for 115-118 hp.

 

[SLEDBUNNYRACING]

I'll have to post a video of it running...regardless of how much power it has...it's one of the best sounding 670's around....Putt...Putt...Putt
A good sound is so important.

 

[jay007]

I have a 97 670 summit, and love it, bullet proof engine, the most reliable sled I have ever had. Bought a newer one for the bigger track and climbing ability, but can't seem to part with the 670, just love that machine.

 

[Armilite]

====>The regular 670 was rated at 115hp and the 670x or 670ho had 128hp .....

At what RPM?
Rich

 

[magnet]

====>The regular 670 was rated at 115hp and the 670x or 670ho had 128hp .....

At what RPM?
Rich

i think they rated them at 8200 or 7800 if i remmeber right. best engine sled combo hands down i think anyways for the day engine was indestructable, that and the 583 best engines for sleds ever built.