What blend of race fuel for mcx?
- Thread starter SAWYER
- Start date
Do you know how thick the head shim is? If you know the thickness of your shim I can calculate the compression ratio and let you knnow for sure, but typically below 5000 feet I like to see that setup running 112-114 octane. We have had good luck with Sunococ and VP.
100 Octane works for me 
According to MCX's website:
"We can now offer an upgrade kit to 270 hp that includes a new fuel pump and fuel pressure regulator +some more parts. The EFI box also needs to be re-mapped.
Petrol quality: 98 okt (Europe) Premium only (USA, Can)"
Anyone have this update kit yet? Is it possible to get 270hp on pump gas? I'd like to hear more about this.
"We can now offer an upgrade kit to 270 hp that includes a new fuel pump and fuel pressure regulator +some more parts. The EFI box also needs to be re-mapped.
Petrol quality: 98 okt (Europe) Premium only (USA, Can)"
Anyone have this update kit yet? Is it possible to get 270hp on pump gas? I'd like to hear more about this.
Pmed you viper
I had one of last year's early kits that came with the pump and mapping but I didn't chance it on 91 octane premium. I don't think I'd feel comfortable running 17psi on pump without some form of detonation control. I think the instructions for the new upgrade kit says race fuel.
I haven't read the instructions, but we don't run with any race fuel in our sleds, only the best pump we can get hold of, and that is 93 octane premium.
But with that said, i wouldn't run 17lbs on premium with confidence either, but so far neither of them had any problem, but i fear that day they get a bad batch of fuel in the tank.
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Don't want to hijack the thread, but how thick are the head shims on the MCX kits for the Nytro's.
I was on totally yamaha site and they have a great octance calculator on there. I just need to know the head shim thickness.
I was on totally yamaha site and they have a great octance calculator on there. I just need to know the head shim thickness.
European and North American fuels are not the same. Ours is inferior. Your premium is better than ours.
I sure have heard that before, but octane is the same, and as you know that's what resist knock (main factor anyway) so it's anybodys guess who has the best fuel.
Only because we pay for the gasoline as it is made of gold it doesent have to be
.
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Canadian Premium is only 91 (as long as the delivery guy didn't drop 87 in by mistake) Av is 100.
) Av is 100.
.From what I have heard Sawyer you can go up to 17lbs on the MCX with 50/50 mix of 112/91. You could probably mix in half premium at that boost and be fine.
If the head shime on the Nytro is the same as the Vector you do not need over 100 octane if riding over 3000 feet and you can run up to 17 lbs boost.
Like it says on totally yamaha, for ever pound of boost add 1-1.5 octane minimun, and subtract 1 octane for every 1000 feet elevation.
If the head shime on the Nytro is the same as the Vector you do not need over 100 octane if riding over 3000 feet and you can run up to 17 lbs boost.
Like it says on totally yamaha, for ever pound of boost add 1-1.5 octane minimun, and subtract 1 octane for every 1000 feet elevation.
R
ridehard1212
Active member
What about 94 pump?? better the 91?? In BC almost all petrocan offer 94 and 91. Just wondering/thinking...And i never run the 91 in any of are sleds allways the 94... if they had 98 pump i would run that!! Just drums are a pain in the aszz
Yeah, higher octane mean better resist against knock = safer to run boost.
If we can run on 93 octane, and it seem to be safe, why could't you run on 94 octane even safer, thats my humble opinion.
In Canada they get that 94 octane by adding ethanol. I was told to steer clear and just use 91 as the engines are not made to burn ethanol. I know alot of snowmobile guys run that fuel in there machines, some burn up so don't, I just don't want to chance it.
