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who's running strait pump gas ?

wellfed777

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I'm wondering how many folks are running pump gas or if most turbo owners
end up running race gas or 50/50 or Av gas ?
thanks

let it snow
 

Kenny B

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It has been a goal of mine since I have owned my sled.... I have never been able to get there. Maybe this year with lower compression and vipec ecu taking timing out of the motor..... I have always ended up blending fuel.... :face-icon-small-fro
 

Ski-Dont89

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i ran straight pump fuel in my silber pro several times last year and it ran great. never hit det. but normally i mixed 1 gallon ish of av gas into each tank just to be safe. i was running 7 lbs of boost. put 1000 miles on it this way and still going strong.
 

wellfed777

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thats good to hear what elevation ?

i've talked to a about few riders about fuel and getting consistent
fuel quality and tunning to your fuel and stick with that fuel can be key

i wonder how the performance characteristics change as the boost
is turned up

is lag more likely at higher boost ?

does there seem to be a boost # sweet spot for tree riding
(i guess that might be kit specific)

obviously the power is affected by boost :face-icon-small-sho

let it snow
 

moto_786

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I ran Chevron Supreme Plus which is 94 oct all last year with my MTNTK turbo. Put just over 1500 miles on riding last season at around 7-8lbs of boost riding around the 4500-6500 ft mark with no problems. Only hit det one day a few times my last day of riding I think it was mainly becaus the sled sat for about a month and it was almost 30 deg out and the snow was really heavy.
 

Kenny B

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I probably should have mentioned, I'm at sea level, and our 91 Octane premium fuel is actually more like 87..... So this is the reason I can never run pump fuel. I know alot of guys who are riding in the upper elevations can get away with it. In Newfoundland we also have a **** ton of moisture in the air, which seriously affects the tuning... We make more power up here becuase of the air density, moisture, etc... I had been running 5 to 6 psi for two years, mixed 116 50/50 with our premium, and put on 4600 miles, no issues, ran like a champ. Last year, with a **** ton of mods, water to air intercooler, vipec, heads, T'stat, etc.. I was running 12psi on straight 116. I ran into other problems at this boost, separating pipe, aeromotive fuel pump demanding to much power, etc... With that being said, if I can get the sled to run at 12psi, it was unbelievable, and unstoppable.

My goals for this year are, new engine build from Indy Dan with Boost in mind. New wastegate actuator, returning to stock fuel pump, Self Lubing centre section for the turbo. Tune one, 4 psi on premium pump fuel with Torco accelerator, and another tune with 12 to 15 psi on Straight C116 for when someone talks ****. :face-icon-small-win

C116 is costing me $444 for 10 gallons so I need to get the sled off the good stuff.... She's developing a habit... :face-icon-small-ton
 
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Wheel House Motorsports

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thats good to hear what elevation ?

i've talked to a about few riders about fuel and getting consistent
fuel quality and tunning to your fuel and stick with that fuel can be key

i wonder how the performance characteristics change as the boost
is turned up

is lag more likely at higher boost ?

does there seem to be a boost # sweet spot for tree riding
(i guess that might be kit specific)

obviously the power is affected by boost :face-icon-small-sho

let it snow
7# is kinda the sweet spot IMO for kick *** power and not slinging huge clutching to handle the big power, also, still fairly linear power so easy to ride. once you start getting up 9+ psi its so hard to ride them as they get clutch lag due to fat weights and steep helixes. also, they come on so damn hard its really rough to hold on. they just wear you out as your on and off so much to keep under control. If your riding super deep pow and more open terrain its fun, but if your just bombing around in the woods its really overkill IMO

and most kits if your riding wester US, 7# is just a little av/race mixed in with pump for saftey. I have ridden silber setups from 6K and up on straight 91 with good results but seems like the gas is hit or miss so a gallon or two of av per tank is just hard to argue with for saftey and $5 per ride...
 

wellfed777

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whos kit ? are you running 92 non eth ? do you stay around 1000' when riding ?

thanks

let it snow
 

kanedog

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Never even considered running pump gas. Always avgas or better. I don't know why this topic keeps coming up.
Probably because some clown turbo company markets a "pump gas turbo." Ya, ok. They also are laughing all the way the bank knowing full well that you will spend at minimum, 50% of the turbo cost on repairs at their shop. Dam, I'm opinionated today.
Do a quick search on compression ratios, boost PSI and altitude relationship. You will have a heart attack when you find out how high of octane is required.
 

Wheel House Motorsports

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very true, some kits may be able to get away with it, but on a 2 stroke. I really like to recommend a small blend minimum of av/race fuels. Just not worth the risk, chances are you got at least $10k into your sled. sucks to blow it up over $10 in fuel savings
 

wellfed777

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kanedog your getting fired up again :face-icon-small-hap

i was curious as to what turbo riders have disscovered on using pump fuel
i agree adding some race or av is probably the safest bet

thanks for your 2 cents
 
V

Vi-PEC Powersports

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I personaly ran last year a Vi-pec powersports Ecu on an Hm Turbos kit (not available this year since aerocharger decided to cut hm turbos at the last minute in july because he was selling 25 times aero's volume and wasn't able to swallow the pill) on 1000cc injectors on straight 91 pump gas at 6.5 psi between 300ft to 1200ft here in Quebec, Canada.
One thing to remember is the stock injectors are maxed out at 5.5psi hitting 100% duty cycle most of the time therefore detonating the sled (running out on fuel), not because of an octane problem. There is also a gearing problem that can cause loose spark plugs (very frequent on belt driven system like the Pro Rmk). With the extra power, you are rapidely hitting max gearing wich create too much pressure inside the combustion chamber and loosing plugs, no detonation, too much pressure unable to exit fast enough, snapping rings, pins causing all kinda damages. On my 2014 Pro, i can, at will, loose the plugs on groom trail or areas where snow is not deep enough. A 2 stroke turbo engine need to be loaded all the time and there is a thin error margin if loosing the track in the air or simply achieving max gearing combination, wich i hate the belt driven pros. I am now back to a chaincase 2015 like my 11-12 rmk and will gear the sled according to my setup.
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Ski-Dont89

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interesting. i had a spark plug loosen up on my pro last winter. and you're saying its because of reaching full shift when not under a load?
 

Ski-Dont89

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Never even considered running pump gas. Always avgas or better. I don't know why this topic keeps coming up.
Probably because some clown turbo company markets a "pump gas turbo." Ya, ok. They also are laughing all the way the bank knowing full well that you will spend at minimum, 50% of the turbo cost on repairs at their shop. Dam, I'm opinionated today.
Do a quick search on compression ratios, boost PSI and altitude relationship. You will have a heart attack when you find out how high of octane is required.

odd. i tried running straight av in mine a few times and it ran ok. but it seems to run better with straight 91 pump and a gallon or two of av.
 
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