Can´t find info regarding this anywhere.
Anybody knows what the stock head comp on a M8 is?
Thanks!
Anybody knows what the stock head comp on a M8 is?
Thanks!
M8 stock head comp
- Thread starter Runner8
- Start date
07/m8 is 6.39 to 1
Arctic Cat Engine
Specifications
* F-Series/Crossfire
** M-Series
ITEM 370 cc 500 cc 570 cc 600 cc 800 cc 1000 cc
Engine Model Number AA37A9 AX50L6 AA56A6 AJ60L4 AB80L1 AB10L1
Compression Ratio 6.30:1 6.38:1 6.41:1 6.46:1 6.39:1 6.41:1
Arctic Cat Engine
Specifications
* F-Series/Crossfire
** M-Series
ITEM 370 cc 500 cc 570 cc 600 cc 800 cc 1000 cc
Engine Model Number AA37A9 AX50L6 AA56A6 AJ60L4 AB80L1 AB10L1
Compression Ratio 6.30:1 6.38:1 6.41:1 6.46:1 6.39:1 6.41:1
?
Seriously?
I run a 13:1 RKT head. Think it´s to much compression, even though I specified at what elevation I ride. 0-5000ft, but mostly around 1500-2000ft.
What elevation is the 13:1 head made for?
Seriously?
I run a 13:1 RKT head. Think it´s to much compression, even though I specified at what elevation I ride. 0-5000ft, but mostly around 1500-2000ft.
What elevation is the 13:1 head made for?
Boy if you figures are correct (stock-6.39-1) yours (13-1) I would be filling my pants...the quality of fuel now adays is not what it used to be. Did kelsey sell you that head (for that elevation). Call him and ask him, he is a stand up guy and is most qualified to answer this. Maybe he will chime in here as I am wondering if a head for my 8 future also....keep us posted....garry
i run the 13 to 1 head at 2300 ft...with 91 octane...i am told that its safe...it never activated my det sensor running it regular 91 but for safe guard i just started adding two gallons of 111 race fuel with 8 gallons 91 octane...the 13 to 1 i think is considered a low elevation application..?? mine is Terra -Alps..
Head comp
Thatbis not right the 6.89 -1 is some other way to measure it the stock head is like 12.5-1 I run a 14-1 head at 6-8 K
Thatbis not right the 6.89 -1 is some other way to measure it the stock head is like 12.5-1 I run a 14-1 head at 6-8 K
What is safe to run on a two stroke at sea level???? 2000???? 4000?????ect.
What elevation, and what colour on your plugs?
I run 98 oct, and my plugs are almost white. How`s the colour of your plugs, when you were running only 91 oct?
Going to check plugs at 1500ft within a few days. If white, the head goes off and will be replaced by the stock one!
Already have one.
Has to be said that I checked my plugs at sea level+, and as mentioned before - I`m going to check them again at 1500ft.
M
minet
Well-known member
maybe just add some fuel,
my flatland set up is a 925/700 speedwerx and i just pulled the head yesterday to see whats going on, looks fine,, well a little rich even.
0 feet and 1500 feet are pretty close i dont think you would need much of a different fuel map for those two
my flatland set up is a 925/700 speedwerx and i just pulled the head yesterday to see whats going on, looks fine,, well a little rich even.
0 feet and 1500 feet are pretty close i dont think you would need much of a different fuel map for those two
D
diggerdown
Well-known member
Race fuel will burn almost white. How is your wash?
98 oct
98 octane is not race fuel, it´s pump gas here in Norway. I had the exhaust valves out last week - some black surface, not much wash..
Just have to give it a bit fuel, eh?
Don`t recall my BD #, but it´s on the + side , for sure..
98 octane is not race fuel, it´s pump gas here in Norway. I had the exhaust valves out last week - some black surface, not much wash..
Just have to give it a bit fuel, eh?
Don`t recall my BD #, but it´s on the + side , for sure..
D
diggerdown
Well-known member
I never realized they ran that kind of octane over there. 92 is as high as you find in the states.
my plugs are fine...but there is a lean spot 5500 rpm to 6700 rpm (30-40 mph)that if you stay in that area runs dangerously lean even with a box...if you richen it in that area then you have low end bog..so i just throttle through this range...im going to get my box remapped so that it doesn;t affect the fuel supply untill 4900 rpm so i can adjust the lean area and not have low end bog...i don;t need extra fuel in the low end...
S
skiarisfan624
New member
i got a crossfire 800 and i have it stock and it is two stroke. i live on the coast of alaska and the settings are for 0 to 5000 feet. i rode it at 6500 and it was just fine if you ask me, but i was pretty high up there
Yes, I also have a lean spot, about 6-68-6900, and had a bog there too. I added fuel at 6700 mid, and the bog went away. The exhaust temps keep increasing when in this rpm range, no matter what. Adding fuel doesn`t affect it at all. That`s just the way it is..
Also have a bog at 41-4300, and this bog has always been there. Both before/after mods. Add/subtract fuel - no change.
And from idle, when I pin the throttle, it won`t clear up. Like it`s only running on one cylinder. Have to blip the throttle, then pin it..
