tuning AFR question
04-29-2010, 01:52 PM
#1
Burning Brakes
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tuning AFR question
Hi,
I've been tuning my AFR lately and have some questions. I am running 1 bar of boost and get a constant 11.8:1 at WOT up to redline. From previous discussions, I have read reccomendations for slightly leaner or richer AFR target conditions. My question is what is the difference in spoolup and hp/tq values for say an AFR or either 11:1 or 12.5:1 at the same engine speed/boost. Would it be desirable to tune richer or leaner while boost builds for improved spoolup? Thanks in advance!
-Nick
I've been tuning my AFR lately and have some questions. I am running 1 bar of boost and get a constant 11.8:1 at WOT up to redline. From previous discussions, I have read reccomendations for slightly leaner or richer AFR target conditions. My question is what is the difference in spoolup and hp/tq values for say an AFR or either 11:1 or 12.5:1 at the same engine speed/boost. Would it be desirable to tune richer or leaner while boost builds for improved spoolup? Thanks in advance!
-Nick
04-29-2010, 02:57 PM
#2
Rennlist Member
12.5:1 will give you more power; it's actually the right air/fuel for power.
Most here will run into the mid-high elevens because of the added safety gained with a barely noticeably drop in power. Low elevens you will notice the power drop a bit.
For spool-up that would be pre max power; therefore you can be leaner (even leaner than 12.5), only for that short time before you hit higher boost levels. I think leaner generally gives hotter exhaust and heat helps to spin the turbine.
Most here will run into the mid-high elevens because of the added safety gained with a barely noticeably drop in power. Low elevens you will notice the power drop a bit.
For spool-up that would be pre max power; therefore you can be leaner (even leaner than 12.5), only for that short time before you hit higher boost levels. I think leaner generally gives hotter exhaust and heat helps to spin the turbine.
That pretty much covers it. Mine is in the 11's at wot because it's safer but I understand the above to be correct.
