Exotic-metal55

What A/F range is everyone keeping their A/F ratio? 11.5 and lower?

Anyone seeing 12.0 and higher on their Dyno tunes for A/F ratio?

There has to be hundreds of of A/F ratio dyno sheets in customers hands now.. Post away!

Exotic-metal55

I guess some of the A/F`s must be secret but here are a few to get the party started.

I am searching for a few more posted A/f`s from the past..


Here is one to start with (see pic)..

Finney just posted that he likes 11.0 , as he said "spot on". (see shock to awe thread post #352) 11.0 is pretty standard for S/C, turbo or nitrous engines but what is everyone running on our 55`s?

chiromikey

I think our s/c cars like a tad leaner than the turbos...mid 11's for me.

TopGun32

at which point of the rpm is the A/F ratio most important?

I'm at around 12 A/F at my max hp! 472 RWHP on dynojet numbers

before than the A/F is a bit higher. I do have a small intake mod that pulls in a bit more air.

cahiil55k

11.75 for me at 460rwhp / 5800rpm.

bassn_07

At redline I'm hitting 11.8 sniffing through the tailpipe

stevebez

As rpm climb you want to go richer as more heat is present (and possibility of detonation) at higher rpm. Leaner at 3000rpm is good for economy too.

S/C slighty less serious I would say than turbo's as the boost tails off as rpm rise with S/C turbo is much more sensitive at higher rpm.

lowprofile

IMO you can't back up a blanket statement like, "this is the optimal a/f for everyone". Real world results from those above would indicate that mid to high 11's are optimal, for them. You also need to consider that both chiromikey and bassn_07 have well built i/c systems which lowers their IAT's and would allow a leaner mixture while still being safe. As well, there is no mention of timing figures which also plays a role in determining a/f.

TopGun32

I agree as well.
additional H/E or swapping for a bigger unit not only reduced the peak IAT but reduced recovery time of temps

I'm getting a Tstat soon and I hope to knock of a few more degrees during cruising IAT's.

Exotic-metal55

Curious,, where did you find the blanket statement that you quoted or mentioned? Was a post deleted today?

lowprofile

No, the post wasn't deleted. I was referring to the thread you mentioned where Finny stated, "... 11:1 is the best ratio for the Komp mill..."
While that might have been "best" for him and his setup, there are too many variables to say that applies to everyone, that's all.

Exotic-metal55

I agree as well, that is a blanket. Just posting graphs and info from others on A/R only. Disclaimer: This info in this thread is by in no means a way to tune your car from, set timing, A/R alone or even use to demand that your tuner set your A/R the same as another person that replied.

Just to clarify my thread, I was just looking to see what people have their A/R set up at on the dyno. Nothing more and not saying any of this is safe or a way to tune a car..Just seeing what numbers we came up with as a forum.

I am curious how many people are running above 12 to 1?? Not saying these numbers are Safe for each car and would have no way to tell based on all the factors it takes to make a car run safe. I have seen plenty of cars LIVE on a dyno and then blow the first WOT run in the real world.

Many of us have temp ranges from summer to winter of 80 deg delta. That ccan equate to 5000-6000 D/A swings. What happens to fuel /boost and timing from one extreme to other and the tune that may have been done on a static dyno at 100 deg heat. so yes, many factors but just looking for A/R ratios on this thread and hope to see some graphs to talk about..


Load those dyno grapjs with A/R!!!

OJPAMG

Ive been a tuner on american cars for 10 years now using aftermarket ECUs that run odd wideband sensors.
with that being said this is kinda of a general question and my answer would revolve around how much boost an individual car is running.
I wouldnt tune to 11.1 if your running 12#s of boost is basically what i am saying.
So it would be cool if posters could post their A/F along with their max boost at wide open throttle.
Now does anyone have a link to software I can use to tune the Benz factory ECU,I really want to get in there

Exotic-metal55

I think most of us with pulley`s are running 14-15lbs of boost.