KCLV post tune data logging
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From: Ma
KCLV post tune data logging
I went to the dyno last week and on my first pull i threw an O2 sensor CEL and only put down 379WHP with ppe headers and borla exhaust. I went to see chris (RCB) to fix the CEL which we did (it was a bad O2 sensor). During this week hooked up his laptop because i was curious what my knock correction learning value was at and it was at 17.9. At the time we assumed it was because of the bad O2 sensor.
I reset the ecu and drove for about 150 miles with 20-30 4th gear pulls and went back to see him today. We hook up the laptop and the KCLV is reading 18.1 so we go for a ride and do some pulls and under WOT it dropped to 17.4 and then would go back up to 18.1 when cruising. It did this consistently and we are not sure why my KCLV doesn't seem to climb any higher than 18.1. Im hoping theres something simple I'm missing but I'm skeptical.
I reset the ecu and drove for about 150 miles with 20-30 4th gear pulls and went back to see him today. We hook up the laptop and the KCLV is reading 18.1 so we go for a ride and do some pulls and under WOT it dropped to 17.4 and then would go back up to 18.1 when cruising. It did this consistently and we are not sure why my KCLV doesn't seem to climb any higher than 18.1. Im hoping theres something simple I'm missing but I'm skeptical.
^^ misterskiz is right. I think the ecu is still detecting knock. Try some higher octane gas if it's available to you. I know mixing some race gas into 91 octane will get better results and faster learning curve.
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From: Ma
I only use 93 octane. I'll try resetting again but doing 7th or 8th gear pulls isn't exactly easy to do on the road. Is it possible the gas I'm using is still "winterized". I'm not sure exactly what that term means but I've seen it used.
I don't think they mean do top speed runs in 7th or 8th gear. I believe what they mean is to get the car into 7th or 8th gear at a low rpm and floor it, not to top speed, just to build load on the car. If I understood them correctly from another thread, this is what they do to get the knock levels over 20.
Pole Position
Joined: Sep 2012
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From: Greenville, SC
I don't think they mean do top speed runs in 7th or 8th gear. I believe what they mean is to get the car into 7th or 8th gear at a low rpm and floor it, not to top speed, just to build load on the car. If I understood them correctly from another thread, this is what they do to get the knock levels over 20.
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From: Ma
A little update, I reset my ecu and took a ride to borrow Chris' laptop with tech stream for a couple days. 8th gear pulls is definitely the way to go in the 28 mile round trip I got the value up to 20.3 and it was as high as 21.7. I do have a 133k on my car so Chris thinks it's a good idea to do the valve lash inspection which I completely agree with. I will update after I hit the dyno Tuesday and track Wednesday night.
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EPA established a two-phase reduction in summertime commercial gasoline volatility. These rules reduce gasoline emissions of volatile organic compounds (VOC) that are a major contributor to ground-level ozone (smog). Phase I was applicable to calendar years 1989 through 1991. Depending on the state and month, gasoline RVP was not to exceed 10.5 pounds per square inch (psi), 9.5 psi, or 9.0 psi. Phase II is applicable to 1992 and later calendar years.
https://www.epa.gov/gasoline-standar...vapor-pressure
The important thing to remember is it shouldn't matter if it's summer or winter blend. That's just a system set up to try and limit evaporation.
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From: Ma
Unfortunately my wife took the ride me and she absolutely hates aggressive driving. She's a cop in town which definitely has its benefits though for people like myself with a heavy foot. Luckily, those 8th gear pulls from 55-100 she didn't say ****. I'm gonna push it solo tomorrow and I'll let you know how the butt dyno goes.
Thread Starter
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From: Ma
Volatility is the property of a liquid fuel that defines its evaporation characteristics. RVP is an abbreviation for "Reid vapor pressure," a common measure of and generic term for gasoline volatility. EPA regulates the vapor pressure of gasoline sold at retail stations during the summer ozone season (June 1 to September 15) to reduce evaporative emissions from gasoline that contribute to ground-level ozone and diminish the effects of ozone-related health problems.
EPA established a two-phase reduction in summertime commercial gasoline volatility. These rules reduce gasoline emissions of volatile organic compounds (VOC) that are a major contributor to ground-level ozone (smog). Phase I was applicable to calendar years 1989 through 1991. Depending on the state and month, gasoline RVP was not to exceed 10.5 pounds per square inch (psi), 9.5 psi, or 9.0 psi. Phase II is applicable to 1992 and later calendar years.
https://www.epa.gov/gasoline-standar...vapor-pressure
The important thing to remember is it shouldn't matter if it's summer or winter blend. That's just a system set up to try and limit evaporation.
EPA established a two-phase reduction in summertime commercial gasoline volatility. These rules reduce gasoline emissions of volatile organic compounds (VOC) that are a major contributor to ground-level ozone (smog). Phase I was applicable to calendar years 1989 through 1991. Depending on the state and month, gasoline RVP was not to exceed 10.5 pounds per square inch (psi), 9.5 psi, or 9.0 psi. Phase II is applicable to 1992 and later calendar years.
https://www.epa.gov/gasoline-standar...vapor-pressure
The important thing to remember is it shouldn't matter if it's summer or winter blend. That's just a system set up to try and limit evaporation.
Thread Starter
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From: Ma
I did some more pulls today and on high load 8th gear pulls the kclv was at 21-22. Obviously my next move was to down shift and do a few WOT runs in 2-4th and that number would consistently drop to around 19. Is this normal?
Pole Position
Joined: Sep 2012
Posts: 244
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From: Greenville, SC
The other value to watch is knock feedback. This normally reads -3.0 but if the knock sensors are detecting ping it will go more negative. If they are not detecting ping at high load situations it will go up (less negative). After several pulls where the number goes up (closer to zero) the KCLV will go up. If it continues to go more negative, KCLV will go down.
I think you should be higher than 19 with all the high gear pulls you have made which means you are likely getting knock. To rule out valve noise put some 100 octane in and see what happens. If it doesn't improve you've got false knock. If it does we need to try to figure why you are pinging.
How long since your last plug change?
I know this is a long shot but check your intake manifold to see if there is any oil. If so, clean it with a VERY LONG screw driver with a microfiber towel attached to the end of the screw driver. It could be possible that overtime, oil has accumulated from the pcv valve which is causing your knock sensors to go back down.