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tgeers
June 8th, 2006, 03:42 PM
Hi,
when going wot at the drag strip, what kind of AFR numbers are you looking for? I am guessing you want to be a little on the rich side, but how much?
Someone told me to tune the car to run at 13.5 afr down the track. What are your thoughts on this? I sure would appreciate your advise.

Thanks

Tony

superls1
June 9th, 2006, 01:14 AM
What is the primary purpose of the car and how long do you want it to live? 13.5:1 is a little too lean in my opinion. If it is a daily driver and you don't have deep pockets (like most of us), then I would should for something more like 12.8:1. But that's just me. I don't think you will be giving up much if any (in terms of performance), it provides some safety, etc. You will only go too lean once. :)

SSpdDmon
June 9th, 2006, 01:53 AM
I stand by the idea of running 12.2~12.3 at peak torque and 12.8~12.9 at peak horsepower with nice smooth transitions inbetween. 13.5 is too lean if you ask me.

Dirk Diggler
June 9th, 2006, 02:12 AM
13.5 is too lean I usually shoot for 13.0

98SS2836
June 9th, 2006, 02:26 AM
shoot for around 13.00

dfe1
June 9th, 2006, 06:06 AM
The theory is that 12.9-13.0 produces maximum power on naturally aspirated engines. The reality is, if you live by absolute numbers, you'll die by absolute numbers. Start in the 12.9-13.0 range and experiment, find out what the engine wants, then dial in a little safety margin. You want to be slightly richer than the AFR that produces max power. Keep in mind that even if they are being controlled digitally, engines are analog devices

tgeers
June 9th, 2006, 08:45 AM
Thanks for the advise. I will start with 13.0 and see what happens. My corvette is a daily driver that runs in the 10's at the track. I surely do not want to break it (again)!!!!!

Thanks again for your replys and help.

ace68
June 9th, 2006, 09:21 AM
I ran faster at 12.6 the whole way down the track. I did 13.1 at the top of the track and lost a little time.

98SS2836
June 9th, 2006, 09:26 AM
I ran faster at 12.6 the whole way down the track. I did 13.1 at the top of the track and lost a little time.

Ya NED like's It a little richer you'll put down a better number on the dyno at 13:1 but run slower up there.

superls1
June 9th, 2006, 02:13 PM
Thanks for the advise. I will start with 13.0 and see what happens. My corvette is a daily driver that runs in the 10's at the track. I surely do not want to break it (again)!!!!!

Thanks again for your replys and help.

What are the mods and what are the times/mph? Not too many 10 second C5's N/A daily drivers. ;) I had a 383 with a big solid roller (244/253 .689/.698 108 in my 01 C5. I could drive to the track and run high 10's (10.80 - 10.96) with the DA 1600' or better. I could get 24+ MPG on the way to and from the track. :) I did get tired of it as a daily driver and eventually bought a used pick-up (supercharged Dakota R/T :) )