Anyone running 100LL fuel in their turbo?
- Thread starter Catman 42
- Start date
I did dyno pulls on my 07 M8 all day yesterday. Running pure 100ll and 10 lbs of boost. It was 60 degrees out and at 4500 feet. NO detonation whatsoever.
I love avgas.
I love avgas.
Av
1850 miles on Av
1850 miles on Av
Thanks for the specific information. What turbo system you have? Any try to go above 10lbs?
I'm running my own turbo kit. I've got both an EVOIII kit and a GT2871R kit that I made up. The kits run the stock pipe (not welded) and the exhaust comes out the stock location. Its sort of a mix between a push and cutler kit but is quiet and doesnt require any holes in your tunnel, or welding of your pipe, but isn't mounted "backwards" like cutlers and has a full 12" silencer. I havent tried to go over 10lbs yet, but I certainly will be soon. Last year on my boondocker TM7 I ran 10 lbs on avgas all year with no detonation at all.
I'm doing the dyno pulls at my house in Kaysville UT, hence the 4500 feet elevation. I think that 60 degrees and that altitude is a pretty bad situation for knock and think that 10 lbs is certainly safe at sledding elevation around here. I'm curious to see if 15-18 lbs is OK on avgas at elevation? There are a lot of opinions on snowest of what is acceptable, but if guys are running 8lbs on pumpgas at 7000 feet, I feel like avgas has got to be good for at least 12 lbs. Mix in a water/air intercooler to keep charge temps down and I thinik 15-18 lbs is pretty reasonable. I will be finding this out through my own testing.
My research into the leaded fuels is that pump gas dramatically reduces the anti-knock properties of the fuel. Its not a 50-50 ratio. Meaning if I mix 5 gallons of 110 octane, and 5 gallons of 90 octane, the resulting octane is not 100 ie (110+90)/2. It is more like 95.
To me this makes sense as the tetra ethyl lead can only go so far. There are a lot of other things about avgas and race gas that give it such high octane. There are also a lot of other things about premium gas that give it such "low" octane. I know there are differing opinions on this and I don't have hard research to back this up, regardless, i'll be doing all of my testing with straight avgas and I will go until I see some deto.
Its for that reason that I run straight avgas. $4 a gallon equates to about an extra $10-$15 a tank. More than worth it in my opinion!
My practical evidence of this is with my CNG 8.1 suburban. My CNG kit has the capability to run gasoline and CNG at the same time. CNG has an octane of 130 and burns pretty slowly. The 8.1 engine was not made to run on high octane fuel and timing wont advance enough to really burn the CNG. I really feel it at higher RPM's, BUT if I mix even 5% gasoline with the CNG over say 3000 RPM, it makes a huge difference.
On a side note, other interesting things I have found on my dyno:
on my 07 M8 in stock form the best power was made at 7550 RPM (I tested all the way up to 8200RPM)
My stock injectors and fuel pump flow 130 lb/hr at 100% duty cycle and 50 psi. This is a theoretical 216 horsepower.
Removing all of the stock airbox equipment resulted in a 12% decrease in overall power
My GT2871r kit makes 51% power over stock at 8 lbs of boost.
Haven't played with the EVOIII kit, but will be.
I'm doing the dyno pulls at my house in Kaysville UT, hence the 4500 feet elevation. I think that 60 degrees and that altitude is a pretty bad situation for knock and think that 10 lbs is certainly safe at sledding elevation around here. I'm curious to see if 15-18 lbs is OK on avgas at elevation? There are a lot of opinions on snowest of what is acceptable, but if guys are running 8lbs on pumpgas at 7000 feet, I feel like avgas has got to be good for at least 12 lbs. Mix in a water/air intercooler to keep charge temps down and I thinik 15-18 lbs is pretty reasonable. I will be finding this out through my own testing.
My research into the leaded fuels is that pump gas dramatically reduces the anti-knock properties of the fuel. Its not a 50-50 ratio. Meaning if I mix 5 gallons of 110 octane, and 5 gallons of 90 octane, the resulting octane is not 100 ie (110+90)/2. It is more like 95.
To me this makes sense as the tetra ethyl lead can only go so far. There are a lot of other things about avgas and race gas that give it such high octane. There are also a lot of other things about premium gas that give it such "low" octane. I know there are differing opinions on this and I don't have hard research to back this up, regardless, i'll be doing all of my testing with straight avgas and I will go until I see some deto.
Its for that reason that I run straight avgas. $4 a gallon equates to about an extra $10-$15 a tank. More than worth it in my opinion!
My practical evidence of this is with my CNG 8.1 suburban. My CNG kit has the capability to run gasoline and CNG at the same time. CNG has an octane of 130 and burns pretty slowly. The 8.1 engine was not made to run on high octane fuel and timing wont advance enough to really burn the CNG. I really feel it at higher RPM's, BUT if I mix even 5% gasoline with the CNG over say 3000 RPM, it makes a huge difference.
On a side note, other interesting things I have found on my dyno:
on my 07 M8 in stock form the best power was made at 7550 RPM (I tested all the way up to 8200RPM)
My stock injectors and fuel pump flow 130 lb/hr at 100% duty cycle and 50 psi. This is a theoretical 216 horsepower.
Removing all of the stock airbox equipment resulted in a 12% decrease in overall power
My GT2871r kit makes 51% power over stock at 8 lbs of boost.
Haven't played with the EVOIII kit, but will be.
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"My stock injectors and fuel pump flow 130 lb/min at 100% duty cycle and 50 psi. This is a theoretical 216 horsepower."
That is an awful lot of fuel per minute. Are you sure you don't mean per hour?
Good info though. I'll be running 100LL this season as well...8/9 pounds boost 5000+ feet. TM-1000
That is an awful lot of fuel per minute. Are you sure you don't mean per hour?
Good info though. I'll be running 100LL this season as well...8/9 pounds boost 5000+ feet. TM-1000
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Heh heh... Yeah, my bad. Definitely 130 lb / hour. I'll update my original post.
100ll
Hi jgw50
Notice your testing is extensive on 2 strokes. Have you by chance done any testing on the 4 stroke motors.
Hi jgw50
Notice your testing is extensive on 2 strokes. Have you by chance done any testing on the 4 stroke motors.
Artic - no testing on 4 strokes yet. I'll be saving my pennies to get a Nytro to mess with, unless Yammi comes out with something new this year.
Daltech - I agree with you on the stock airbox. Its definitely pulse tuned and helps the motor. Only issue is that the airbox and all of its accompanying ducting is very heavy. I think the 12% I saw would be the worse case scenario (like pod filters) but anything added to that could have different effects.
Daltech - I agree with you on the stock airbox. Its definitely pulse tuned and helps the motor. Only issue is that the airbox and all of its accompanying ducting is very heavy. I think the 12% I saw would be the worse case scenario (like pod filters) but anything added to that could have different effects.
im using 2 gal of 100ll every time i fill up with pump on a 09 pg m8 at 8psi and no prob. 2500ft to 6000ft 
Do anyone have any problems with their sleds using 100LL? Thinking on lead build up in the injectors? Plugs?
M
M1000Mod162
Well-known member
would their be anything wrong with running 100% av gas in a race ported n/a m1000? Ive hurd its to dry for the motor. is this true ?
