Setting AFR for the street versus the dyno?
#1
8 Second Club
Thread Starter
iTrader: (18)
Join Date: Oct 2002
Location: Waterloo, Ontario
Posts: 2,609
Likes: 0
Received 0 Likes
on
0 Posts
Setting AFR for the street versus the dyno?
I'm wondering what you guys do when you tune your cars at wot on the dyno? What I have seen on my own car is that if I get my fuel curve down to 12.8 on the dyno at the track the AFR goes considerably leaner. I can uderstand leaning it out on the dyno to see what it can make but before you done to you guys richen the car back up before you leave? If so by how or what's the target AFR?
Thanks!
Thanks!
#3
Restricted User
iTrader: (9)
Join Date: Sep 2002
Location: Sierra Vista, AZ
Posts: 7,603
Likes: 0
Received 0 Likes
on
0 Posts
I dont do the dyno gig, but if I were to tune with a non-loading dyno, I would put it at:
12.5 for NA, results near 13.1 on street
FI is boost level vs engine component dependent, but the STS I am working on:
11:1 street should be 10.5:1 on dyno, new to FI so dont beat me up too bad.
But basically my work with Dynojet nonloading is about .6 leaner on the street.
12.5 for NA, results near 13.1 on street
FI is boost level vs engine component dependent, but the STS I am working on:
11:1 street should be 10.5:1 on dyno, new to FI so dont beat me up too bad.
But basically my work with Dynojet nonloading is about .6 leaner on the street.
#5
TECH Addict
iTrader: (3)
Afr
I have tuned LS1 and LT1 for several years on a DynoJet. The difference is not as drastic as some think. The difference is between .2 to.3. I tune N/A at between 12.8 to 12.9 on the Dyno and it would end up at around 13.0 to 13.2 on the street. On forced inducted I tune to 11.5 to 11.8 depending on how aggressive the timing is. Remember even though the MAF will compensate there will still be a difference in the A/F due to the density of the air....
#7
LS1TECH Sponsor
iTrader: (2)
Originally Posted by slow
how are you guys adjusting the air fuel?
changing the commanded air fuel, through the PE table, or calibrating the transfer function of the maf to match the commanded air fuel ratio?
Ryan
changing the commanded air fuel, through the PE table, or calibrating the transfer function of the maf to match the commanded air fuel ratio?
Ryan
Trending Topics
#8
TECH Senior Member
iTrader: (7)
There are lots of ways to do it, and yes, lots of people will say thier way is best.
But if you are not getting what you are commanding, something in the control system is being lied to to get the desired results. This will increase the chances of the air fuel ratio changing on the street vs the dyno.
Ryan
But if you are not getting what you are commanding, something in the control system is being lied to to get the desired results. This will increase the chances of the air fuel ratio changing on the street vs the dyno.
Ryan
#9
TECH Junkie
iTrader: (36)
I will agree with Ryan on this. I did a car on Friday that was cam only. It took close to 4 hours after all was said and done. What we command on the PE is what we see on the wideband.
I can't comment on what it reads on the dyno as I dont' use a dyno to tune. I normally shoot for around 12.5-13.0 on the street depending on the car and tune needed.
I can't comment on what it reads on the dyno as I dont' use a dyno to tune. I normally shoot for around 12.5-13.0 on the street depending on the car and tune needed.