View Full Version : air fuel ratio
contagious
02-25-2008, 02:34 PM
whats is the best air fuel ratio set up for racing? have a air fuel meter that i got from a friend,and checked my motor.At 4800 to 5000 rpm it is around 14-9 15-2. is that a little lean 509 cid 950 carb
OneBadGMC
02-25-2008, 03:04 PM
That's darn near impossible to answer because of the factors involved.
Intake, exhaust, compression, heads, vacuum, and weather variables play too big of a part of it.
Every motor is going to have it's own 'fine point' with a/f ratio.
What's going to do the most justice for you is to find your best et, noting the a/f ratio and shoot for that ratio as weather conditions change.
Tuning for a specific a/f ratio or egt requires the use of a weather station and a knowledge on jet area as it relates to egt or a/f ratio.
suicidebomb
02-25-2008, 03:40 PM
That's darn near impossible to answer because of the factors involved.
Intake, exhaust, compression, heads, vacuum, and weather variables play too big of a part of it.
Every motor is going to have it's own 'fine point' with a/f ratio.
What's going to do the most justice for you is to find your best et, noting the a/f ratio and shoot for that ratio as weather conditions change.
Tuning for a specific a/f ratio or egt requires the use of a weather station and a knowledge on jet area as it
relates to egt or a/f ratio.
Have you ever used an air density gauge for tuning? are they ok in your opinion? Or does one need a full blown weather station, I realize that they make no provision for humidity, but is ithat much of a drawback?
nova77
02-25-2008, 05:46 PM
i would go to Innovate motorsports . They have a form there and all they talk about is AFR. they can answer an guestion about AFR
OneBadGMC
02-26-2008, 07:15 AM
Never used a density gauge, sorry.
I have a Computech RaceAir Pro 1000.
http://www.computechracing.com/Product_Guide/weatherstation-portable.html
I don't know how I got along before I bought it.