NJGSX96
20+ Year Contributor
- 745
- 2
- Dec 11, 2001
-
YMB,
New Jersey
First, I apologize for the length. I was tempted to post this in Extreme Forum, but hopefully I'll get the guys I need to come in and offer some help and insight.
What is the best way to tune the car to get the most out of it without blowing it up? Do you tune for low knock? Do you tune for low AF (real AF, like wideband)? Do you tune to EGTs? Do you use a combo?
I know a lot of guys running 11s and lower and everytime it comes up, it seems they run with a lot of knock. Some tune to what feels best or yields the most power on the dyno. Others used a wideband O2 to tune to a particular AF ratio. Others just did it by seat of the pants, looking at EGTs. No matter what method they used, they all had a lot of knock, in some instances 43 knock count straight though the run.
I usually tune to knock. Just a touch of knock is where I like it. Gets me great timing advance, good power throughout the run and, for the most part, my car always ran decent. Recently I had some issues at the track, sputtering and pissing down the track from a combo of bad spark and too much fuel and nice cold weather. A couple alternators later, a battery, new plugs and wires and I am ready to hit the track again. Nate at DSMotorsports and I were talking and he lent me his wideband to assist my tuning. He mentioned that he gets lots of knock when tuning to AF ratio, as do many others I know, and to not let it worry me as much as it normally would. All people who tune with the wideband or WB/dyno say the same thing... they couldn't believe how rich they were and they couldn't believe that with a lot of knock they could still run fast. I have now begun to question my tuning methods.
Well today I went to the track, and if you go to the Track Talk section, you can read about it. Background of car... 1G, 95 pistons, 264/264, FMIC, internal gate TD06 20G, built trans, ACT2600, VPC/AFC, 650cc, Eibach/AGX, etc etc. Built pretty good. Compression test is 188 across the board, timing set to 5°, no leaks to 20psi (TB and 1G BOV leak at that point), new lifters, all new sensors. Car is sound. Anyway, I ended up running my best times, on pump gas to boot. I tuned more for seat of the pants and EGT instead of my usual tuning for knock method. I unfortunately didn't have a chance to install the wideband, but I did write down all my settings and logged all my runs to use as reference when I do. Long story longer, each run had gobs of knock and no timing. like 8 count steady dropping in 1st, 8 with a slow drop and then a jump to to 15 by end of 2nd, 15 to 20 to 28 (stepping up in increments) in 3rd and 20 to 30 to 38 (stepping up in increments) in 4th. Like this the car saw 820-840° EGTs and just seemed to go. Car has never felt better. Ever. Throughout the day I took out as much as 10% fuel and the whole time my AF stayed at .84-.86, EGTs 800-840°. Minus the knock and lack of timing, I would say the car is tuned excellent. That knock worries me though. Maybe becuase I always tuned to knock. I don't know.
So what to do? What are the recommendations from the advanced guys here on tuning? Do I stick in the wideband and tune for AF? Do I do the combo of AF and dyno tuning? What AF do I shoot for? What about knock? Do I give it as much notice? Do I got back to tuning for knock?
Any and all help will be greatly appreciated.
Thanks for reading. Again, sorry for the length.
What is the best way to tune the car to get the most out of it without blowing it up? Do you tune for low knock? Do you tune for low AF (real AF, like wideband)? Do you tune to EGTs? Do you use a combo?
I know a lot of guys running 11s and lower and everytime it comes up, it seems they run with a lot of knock. Some tune to what feels best or yields the most power on the dyno. Others used a wideband O2 to tune to a particular AF ratio. Others just did it by seat of the pants, looking at EGTs. No matter what method they used, they all had a lot of knock, in some instances 43 knock count straight though the run.
I usually tune to knock. Just a touch of knock is where I like it. Gets me great timing advance, good power throughout the run and, for the most part, my car always ran decent. Recently I had some issues at the track, sputtering and pissing down the track from a combo of bad spark and too much fuel and nice cold weather. A couple alternators later, a battery, new plugs and wires and I am ready to hit the track again. Nate at DSMotorsports and I were talking and he lent me his wideband to assist my tuning. He mentioned that he gets lots of knock when tuning to AF ratio, as do many others I know, and to not let it worry me as much as it normally would. All people who tune with the wideband or WB/dyno say the same thing... they couldn't believe how rich they were and they couldn't believe that with a lot of knock they could still run fast. I have now begun to question my tuning methods.
Well today I went to the track, and if you go to the Track Talk section, you can read about it. Background of car... 1G, 95 pistons, 264/264, FMIC, internal gate TD06 20G, built trans, ACT2600, VPC/AFC, 650cc, Eibach/AGX, etc etc. Built pretty good. Compression test is 188 across the board, timing set to 5°, no leaks to 20psi (TB and 1G BOV leak at that point), new lifters, all new sensors. Car is sound. Anyway, I ended up running my best times, on pump gas to boot. I tuned more for seat of the pants and EGT instead of my usual tuning for knock method. I unfortunately didn't have a chance to install the wideband, but I did write down all my settings and logged all my runs to use as reference when I do. Long story longer, each run had gobs of knock and no timing. like 8 count steady dropping in 1st, 8 with a slow drop and then a jump to to 15 by end of 2nd, 15 to 20 to 28 (stepping up in increments) in 3rd and 20 to 30 to 38 (stepping up in increments) in 4th. Like this the car saw 820-840° EGTs and just seemed to go. Car has never felt better. Ever. Throughout the day I took out as much as 10% fuel and the whole time my AF stayed at .84-.86, EGTs 800-840°. Minus the knock and lack of timing, I would say the car is tuned excellent. That knock worries me though. Maybe becuase I always tuned to knock. I don't know.
So what to do? What are the recommendations from the advanced guys here on tuning? Do I stick in the wideband and tune for AF? Do I do the combo of AF and dyno tuning? What AF do I shoot for? What about knock? Do I give it as much notice? Do I got back to tuning for knock?
Any and all help will be greatly appreciated.
Thanks for reading. Again, sorry for the length.
