80804-1 850 Ultra XP Tuning

[rgalajda]

This is a chart I made. You may need a passenger for recordings
Carb: Engine: Trans/Axle Ratio: Camshaft:

duration ____@.050 LSA:




Idle AFR Vacuum RPM


In Gear AFR Vacuum RPM


30 MPH AFR Vacuum RPM


40MPH AFR Vacuum RPM


50MPH AFR Vacuum RPM


60MPH AFR Vacuum RPM


70MPH AFR Vacuum RPM


Light/Moderate AFR
Accelerating


Coasting/
deceleration AFR


WOT AFR





Notes: readings taken on flat road / steady throttle

coasting/deceleration on a holley carburetor will almost always go rich

Light/moderate acceleration should go leaner ( not all holley’s do )

Cruise AFR should be at least 14:1 or leaner 

[rgalajda]

I couldn't upload my file so I copy/pasted . Spacing didn't turn out. MPH.............. AFR................Vacuum...............RPM

[80427]

Put in a .78 and it was way lean and had lean misfires. Went with a 1.9mm (.0748") and it seem about right. The next change looks like I need to go from 76 jets to like a 78 or 80. into the 16s at higher speed.

[rgalajda]

Are you using 3/4 turn for idle mixture screws , 4 corners ?

[rgalajda]

[Right hand drive]