air and fuel on and off boost.

[precharge]

Happy new year to all,can someone tell me what should the air and fuel be befor boost comes on and should it be about 10.5- no higher than 11.4?with max boost.Does anyone have any fuel curves to look@ thanks for the help and have a great day.

 

[mtn-doo]

Happy new year to all,can someone tell me what should the air and fuel be befor boost comes on and should it be about 10.5- no higher than 11.4?with max boost.Does anyone have any fuel curves to look@ thanks for the help and have a great day.

I think you're a little fat with those numbers. I would be shooting for 13 to14, but back those up with EGT's. I took my my AFR off and just run EGT's. Clean efficient range on EGT's is in the 900's to 1000's off boost, and high 1100's to mid 1200's on boost at 12 LBS.

 

[precharge]

Thanks for the info first boosted sled and lots of ? afr is @10.5TO 11.5 ON BOOST AND OFF BOOST AFR IS 13 TO 15.5 ARE THESE NUMBERS IN THAT RANGE OR MORE FUEL NEEDED IN THE MID RANGE WHILE OFF BOOST?

 

[Wheel House Motorsports]

off boost cruising light throttle, around 14-13 or so.. wot around 12-12.5.. anything lower then 11.5 your gonna start trailing off on power. much over 12.5 wot your getting a little on the lean side for long pulls.

 

[precharge]

is these numbers with pump gas or race fuel?

 

[AdvancedDyno]

off boost cruising light throttle, around 14-13 or so.. wot around 12-12.5.. anything lower then 11.5 your gonna start trailing off on power. much over 12.5 wot your getting a little on the lean side for long pulls.

The question that needs to be asked is what kind of sled he is driving, run a boosted 1200 doo at 12.5 under boost and you'll have a set of ashtray's
Is it a 2 stroke or a 4 stroke, what kind of fuel is he running,what elevation?

Please include more info.

Cliff Yeatman
Advanced Dyno

 

[precharge]

1200 ski-doo pump gas 5-6 pounds boost

 

[AdvancedDyno]

1200 ski-doo pump gas 5-6 pounds boost

What elevation do you run at, this makes a big difference on A/f.

Cliff Yeatman
Advanced dyno

 

[brycter]

We have run ours at 12.5-12.8 sometimes i see it hit 13.2-13.5. this is the way it has been since day one on our sled. we run it at 6500-11000 feet and have never ever had any problems. At least in the 1500 miles that we have on this sled.

I agree if you can keep it into the 11.5 -11.8 rnage you will be in the swwet spot for most 1200 but ours and another one of our customers likes it a bit higher.

Also we do it a but differnt than the other guys out there, we run a 2-1 rising regulator, high flow fuel pump, different pick ups in the tank, attutude/ dobeck box and stock injector. we run at 12-15 psi and have never ran out of fuel unless we get to 20 psi.

 

[precharge]

What elevation do you run at, this makes a big difference on A/f.

Cliff Yeatman
Advanced dyno

HI CLIFF I RUN DOWN @ 2500 FEET

 

[precharge]

Hi is this on pump gas or race gas?

 

[supraturbo]

at 2500 ft and 5-6 lbs boost, premium gas(91 octane) you are fine at 14 to 14.7 cruising and wot 11.8 to 12.2( long pulls) if just climbing and wot for 10-15 seconds than 12.5 would be ok.

 

[precharge]

at 2500 ft and 5-6 lbs boost, premium gas(91 octane) you are fine at 14 to 14.7 cruising and wot 11.8 to 12.2( long pulls) if just climbing and wot for 10-15 seconds than 12.5 would be ok.

Thanks for these numbers.

 

[hivoltagesledhead]

What would be the proper numbers for an 800 2 stroke with 10-12 lbs boost on race/pump combo at 3000-7000 and sometimes up to 10,000 ft. I was told 11.8-12.2

 

[Jbest103]

What kind of air fuel would be good on a turbo etec running straight 118? im seeing 13 to 13.5 at wot on a long pull. Is this too lean?

 

[tonka8ty]

On my etec run it at about 12.8 and my egt reading is about 1250 would not run at 13.5 very long mine did that and egt climes to 1350 not good

 

[Jbest103]

ok sounds good thanks. Is my fuel making it run lean? I have my fuel controller with the settings as rich as i can in boost. I am running straight 118 at 10 lbs boost at about 3000 to 7000 elevation.