Not another Meth injection thread
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Joined: Sep 2011
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2005 corvette
Not another Meth injection thread
I've been lurking on these forums for a few days now and can't seem to find an answer on tuning for Meth injection and ecu failsafes.
I have a good bit of experience with Meth injection on a centrifugal supercharged corvette.
My question is specifically about ECU failsafes and is there any tuners out there that can implement a failsafe using IAT sensor readings to pull timing from a meth tune when it fails. The few admitted users of meth on this board
see temp drops of 80-100deg F on their stock IAT sensor. The factory ECU setting already pulls timing once IAT's rise above 140deg F. So if a tuner had the ability to adjust the temp threshold and amount of timing that is pulled, they could essentially run an aggressive meth tune (lean the A/F ratio, add timing) without any worry of pump failure or empty tank.
Many different cars have the ability to do this and I have had it work flawlessly on my corvette. The way it works currently on my car is My IAT's without meth are about 140deg F with a 100deg F ambient temp. The ecu is set to pull 10 degrees of timing advance at temps of 110deg F or over. This not only pulls the 5 degrees of advance that the meth allows for over pump gas but it also pulls enough timing to make up for the leaner A/F ratio that you will see with a meth injection failure.
The guys using meth injection are leaving a considerable amount of power on the table by not tunning for the meth, quite possibly more than 40rwhp.
I have a good bit of experience with Meth injection on a centrifugal supercharged corvette.
My question is specifically about ECU failsafes and is there any tuners out there that can implement a failsafe using IAT sensor readings to pull timing from a meth tune when it fails. The few admitted users of meth on this board
see temp drops of 80-100deg F on their stock IAT sensor. The factory ECU setting already pulls timing once IAT's rise above 140deg F. So if a tuner had the ability to adjust the temp threshold and amount of timing that is pulled, they could essentially run an aggressive meth tune (lean the A/F ratio, add timing) without any worry of pump failure or empty tank.Many different cars have the ability to do this and I have had it work flawlessly on my corvette. The way it works currently on my car is My IAT's without meth are about 140deg F with a 100deg F ambient temp. The ecu is set to pull 10 degrees of timing advance at temps of 110deg F or over. This not only pulls the 5 degrees of advance that the meth allows for over pump gas but it also pulls enough timing to make up for the leaner A/F ratio that you will see with a meth injection failure.
The guys using meth injection are leaving a considerable amount of power on the table by not tunning for the meth, quite possibly more than 40rwhp.
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From: Porter Ranch, CA
E55, CTS-V Wagon, Duc 1098R
Based on talking to Jeremy from OE about it, it's definitely possible but it's not perfect because the car still adapts on timing. His recommendation was not to do it since it isn't ideal. I'd talk to him directly about it given that my car is a daily I didn't want to get surprised.
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2005 corvette
I 'm not worried about what "adapting" the car may do while meth is spraying. I'm worried about what the ucu does once meth stops flowing. Should pull timing just as it would without meth. I'd like to know if the threshold (temp) that the car starts to pull timing can be changed. Also if the amount of timing that is pulled can be adjusted as well.
If people are worried about how fast the IAT sensor reacts to temp changes there are better thermisters out there if stock is insufficient.
If people are worried about how fast the IAT sensor reacts to temp changes there are better thermisters out there if stock is insufficient.
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2005 corvette
I dont understand why this is so difficult. Really is pretty cut and dry for the other platforms out there. Is your tuner having a problem from the transition into and out of boost? A progressive meth spray based on rpm is the ideal way to trigger the spray with a PD/twin screw blower.
Set up a meth tune on the dyno. Monitor what the IAT's are with meth flowing. Add ~20deg F to that as the threshold to pull timing. Then pull a ton of timing once the temps go above that(indicating that meth has failed).
The hardest part is getting the meth tune down. Setting up the fail safe on a properly setup/tuned car should be simple.
Set up a meth tune on the dyno. Monitor what the IAT's are with meth flowing. Add ~20deg F to that as the threshold to pull timing. Then pull a ton of timing once the temps go above that(indicating that meth has failed).
The hardest part is getting the meth tune down. Setting up the fail safe on a properly setup/tuned car should be simple.
Last edited by apsgto; Sep 22, 2011 at 11:06 AM.
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From: Salt Lake City (but not Morm)
2003 E55 & 2014 GL550
Really is pretty cut and dry for the other platforms out there.
It took tuners YEARS to find that damn Trq Manangement maps and adjust them for us. Least Jerry can do it in secs now....that is a GOOD thing.
To have their back for a sec, they say it is some of the hardest tuning they do. The maps and how they are all intertwined is a nightmare to tune.
Vette tuning is cake compared I have been told. I watched a CTSV guy tune his car with off the shelf software in front of me. For us.....(buzzer) zippo
We roll on though. Hopeful and thankful for anything the tuning Gods can give us.
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2005 corvette
Welcome to Benz modding hell. Satan is over there on the right just next to Hitler!
It took tuners YEARS to find that damn Trq Manangement maps and adjust them for us. Least Jerry can do it in secs now....that is a GOOD thing.
To have their back for a sec, they say it is some of the hardest tuning they do. The maps and how they are all intertwined is a nightmare to tune.
Vette tuning is cake compared I have been told. I watched a CTSV guy tune his car with off the shelf software in front of me. For us.....(buzzer) zippo
We roll on though. Hopeful and thankful for anything the tuning Gods can give us.
It took tuners YEARS to find that damn Trq Manangement maps and adjust them for us. Least Jerry can do it in secs now....that is a GOOD thing.
To have their back for a sec, they say it is some of the hardest tuning they do. The maps and how they are all intertwined is a nightmare to tune.
Vette tuning is cake compared I have been told. I watched a CTSV guy tune his car with off the shelf software in front of me. For us.....(buzzer) zippo
We roll on though. Hopeful and thankful for anything the tuning Gods can give us.
