Need help with A/F Ratios????????

[JoyRydn 03]

My 2004 Cobra puts down 501 RWHP and 487 RWTQ with a ported blower, my questions is this!!!! The place that tune my car has my A/F Ratio at 12.3 and 21 degrees of timing,Is 12.3 Rich or lean?????? I'm thinkng it's rich....

Thanks

 

[FartMaster04]

12.3 is lean. The higher the number, the leaner it gets. Should be around 11.8

 

[sambandit]

Little bit on the lean side... Was that through a sniffer though or before the cats?

 

[JoyRydn 03]

Little bit on the lean side... Was that through a sniffer though or before the cats?

This was through the sniffer. The guy who tuned the car is well known and does excellent work. I asked for the car to be tuned on the safe side, I didn't care about the HP I just wanted it to be safe!! So when I got 501 rwhp and great torque to match and what I thought was a safe 12.3 A/F ratio, I thought great.

It took me a long time to find someone that I trusted to work on my car as it only has 3100 miles.

I need to figure out now where togo from here to get the car safe! Thanks for your help! A little surpised that 27 views on this thread and only 2 guys with answers leads me to believe I'm not the only one the doesn't know "Jack shit" about A/F ratios and where these cars are supposed to be on a safe tune??

 

[sambandit]

Well, I definately wouldn't call 12.3 through the tail pipe conservative in anyway. The timing is a couple off of what you could run, so that part of it is safe/conservative. 11.5 at 21 degrees would be very safe and on the conservative side IMHO.

 

[ViciousJay]

joyrdyn where are you in IL???

 

[liedenfrost]

I have a ported blower with a 2.76 upper pulley. My timing is at 22 degrees and my A/F ratio is around 11.6 +/- 0.3 throughout the whole rpm range.

 

[JoyRydn 03]

joyrdyn where are you in IL???

schaumburg

 

[JoyRydn 03]

Well, I definately wouldn't call 12.3 through the tail pipe conservative in anyway. The timing is a couple off of what you could run, so that part of it is safe/conservative. 11.5 at 21 degrees would be very safe and on the conservative side IMHO.

I just called the shop where I had the work done,and spoke with the shop MGR. I coudn't fine the dyno sheet this morning. The guy rememebered the car well not to mention I've known the tuner for 15yrs. He told me not to worry and that my tune at 21 degrees timing was at 11.5-11.6 all the way through and that only on the top end did it start to lean out to about 12.0-12.3 he said if I add the mafia he can get me 11.5-11.6 across the board and never have to worry.

So I guess my 501RWHP and 487 RWTQ @21 degrees timing and 11.5-11.6 A/F ain't so bad. So I'm going to order the mafia today so we can get up to 23 degrees timing and add the fuel needed.


Sorry for the false alarm guys!!! but the A/F deal makes me nervous!