How to Combat that Z06 ECU? Let the Car Break In, Says Chevy Rep
Team Owner
Joined: Nov 2007
Posts: 24,035
Likes: 2,342
From: Gilbert AZ
Same here on all my good running motors. Current 1100+rwhp motor was warmed up, check for leaks, put on dyno and making 900+rwhp pulls with ~20 miles on the motor that was just leak checking. Now 15k miles, best running motor I've ever had. Instructions to break it in hard came from the builder, and I firmly believe break them in like they are meant to be driven.
Former Vendor
Joined: Aug 2001
Posts: 5,798
Likes: 50
From: Dallas & Chicago TX & IL
Ah yes, a man that truly understands engine break-in!
I have spent a lot of time tuning with GM ECM's and I have yet to find a tab in there that limits engine power based on mileage and I have a hard time believing that this is the case with the Z06 because if it was, someone would have already discovered the tab/file that contains this. Sounds like more hogwash without a factual basis because if the ECM did limit power, how do we explain the simple fact that tuners are breaking these motors in on the dyno with ZERO apparent loss in power? This is all the proof I need that this is just another wives tale propagated on the Internet!
I have spent a lot of time tuning with GM ECM's and I have yet to find a tab in there that limits engine power based on mileage and I have a hard time believing that this is the case with the Z06 because if it was, someone would have already discovered the tab/file that contains this. Sounds like more hogwash without a factual basis because if the ECM did limit power, how do we explain the simple fact that tuners are breaking these motors in on the dyno with ZERO apparent loss in power? This is all the proof I need that this is just another wives tale propagated on the Internet!
Nah, I didn't see such thing in the tune files.
Oh, and before I drive my cars like its meant to be driven, I always allow them to warm up - even in the middle of summer
Same here on all my good running motors. Current 1100+rwhp motor was warmed up, check for leaks, put on dyno and making 900+rwhp pulls with ~20 miles on the motor that was just leak checking. Now 15k miles, best running motor I've ever had. Instructions to break it in hard came from the builder, and I firmly believe break them in like they are meant to be driven.
I've been telling people about the real break-in procedure for years, but for some reason they think I'm crazy
Perhaps that is why they always tell me that my cars run harder for some reason. The secret...BREAK-IN
Thanks,
Carlos
Le Mans Master
Joined: May 2007
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From: Havre De Grace, MD/Apalachicola, FL
Burning Brakes
Joined: Jul 2002
Posts: 791
Likes: 52
Ah yes, a man that truly understands engine break-in!
I have spent a lot of time tuning with GM ECM's and I have yet to find a tab in there that limits engine power based on mileage and I have a hard time believing that this is the case with the Z06 because if it was, someone would have already discovered the tab/file that contains this. Sounds like more hogwash without a factual basis because if the ECM did limit power, how do we explain the simple fact that tuners are breaking these motors in on the dyno with ZERO apparent loss in power? This is all the proof I need that this is just another wives tale propagated on the Internet!
I have spent a lot of time tuning with GM ECM's and I have yet to find a tab in there that limits engine power based on mileage and I have a hard time believing that this is the case with the Z06 because if it was, someone would have already discovered the tab/file that contains this. Sounds like more hogwash without a factual basis because if the ECM did limit power, how do we explain the simple fact that tuners are breaking these motors in on the dyno with ZERO apparent loss in power? This is all the proof I need that this is just another wives tale propagated on the Internet!
Team Owner
Joined: Jan 2008
Posts: 30,894
Likes: 1,189
From: chicago
There is a large part of the engine controls that are not in the ECM; but in the BCM. In addition not all of the tables and parameters that are in the ECM are not accessed either. I don't know of any aftermarket tuning suite that allows consumer access to that information.
Melting Slicks
Joined: Aug 2000
Posts: 2,609
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From: Phoenix, AZ USA
BCM's do read miles and hours
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Burning Brakes
Joined: Jul 2002
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Agreed. I have a feeling these cars will loosen after the break in period. This was hotly debated (because that's what car guys do other than driving) when the ZL1 came out. Chevy was very intent on having the owners follow the break in even though some owners insisted on beating the crap out of the car from mile one. It got so bad one of the Camaro team members would repeatedly post. He also recommended to disconnect the battery right after the break in was completed and then let it fly (not his exact words). Below is one of his many posts.
As I've repeated time and time again - we put a break-in period on this particular Camaro Model (The ZL1) for a reason. Our engineers know what they're talking about. We do not require a 1,500 mile break-in period on other Camaro models.
Burning Brakes
Joined: Jan 2008
Posts: 758
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From: Raleigh N.C.
Melting Slicks
Joined: Oct 2007
Posts: 2,398
Likes: 858
Yes. We went through this with the C4 LT4's then again with the C5's and again with the C6's and now again with the C7's. Just to be clear I am talking about break in and a slight (2-3%) power gain after the engine and drivetrain lossens up,and the rings seat.
Melting Slicks
Joined: Aug 2004
Posts: 2,149
Likes: 1,349
From: Big D Dallas TEXAS
The Z06 RPM warning bar will be removed once you hit 500 miles. I am not sure if the ECU is in a special protection mode but the transition from 499 miles to 500 miles during new car break-in... RPM warning bar goes from 3500 to 6500. Watch this C7 video & your RPM warning bar will be removed in your Z06 once you hit 500 miles.
Last edited by fasttoys; Dec 12, 2014 at 11:28 PM.
Team Owner
Joined: Feb 2013
Posts: 22,598
Likes: 14,556
Modern engines break-in almost instantly. The rings seat in the first few seconds of running. Reving up and allowing rev-down and engine loading only helps. Every track engine we've ever broken in we let it run up to temp and then cool down full 2x on organic dino oil. Then I change the oil with dino oil again. Then we hit the dyno to run through the gears and let it rev-down. Then we put synthetic in them and let it eat. After the first track weekend we change the oil again.
GM's break-in recommendations are really for the trans/dif to develop a good wear pattern.
GM's break-in recommendations are really for the trans/dif to develop a good wear pattern.
Melting Slicks
Joined: Oct 2013
Posts: 2,391
Likes: 64
The Z06 RPM warning bar will be removed once you hit 500 miles. I am not sure if the ECU is in a special protection mode but the transition from 499 miles to 500 miles during new car break-in... RPM warning bar goes from 3500 to 6500. Watch this C7 video & your RPM warning bar will be removed in your Z06 once you hit 500 miles.
New C7 Corvette Stingray Breaking-In - YouTube
New C7 Corvette Stingray Breaking-In - YouTube
Burning Brakes
Joined: Dec 2007
Posts: 967
Likes: 6
From: Downers Grove IL
It is not about being ignorant but simply people do not understand all that goes on with OBD designed engines, all it's feedback sensors and how the PCM adjust to changing conditions, different modes of operation, the hard rules pushed onto nameplates as to EPA, SMOG, CARB.
Being the PCM makes adjustments over time, if sitting on some chassis dyno and screwing around for some time there is not going to be the cooler airflow nor since pulls are only couple of minutes the PCM has little chance to make adjustments for hotter air temps and every time the car is turned off and then another pull done then the PCM adjusting has to start over
Add those who are bashing about heat soaking are also screwing with the tune and as such made claims the tune is conservative, hence you know they are jacking up the timing tables and worse not properly tuning other tables for fuel, airmass, knock, misfires, etc, etc and making the problems out of bounds to a correct tune
Since a supercharger is compressing the air that causes the air to get hotter, the more heat the more the air expands which then means there is less molecules per volume which means the cylinder burn is not very good
Add E10 or E10 gas and the total means leaner, hotter, more knock and the PCM as designed to protect the engine will pull timing ( if engine is running longer enough for that drive cycle)
Strapped down on a dyno with no real cooler airflow and the inner cooler for intake cannot do it's job
Add hood left open and pressure is lost so that even the fan for radiator is useless.
The PCM has like 2 meg bytes of content, that means there is countless functions and tables that are used so simple "heat soak" involves many of them and they cannot be properly used in short runs on a chassis dyno
GM protects the engine for the first 500 miles, anyone banging on the LT4 and making claims have zero clue about any of this and are doing BS marketing as the engine broke in and then allowing PCM to fully adapt will have totally different results.
All these functions have existed since the C4 Corvette and we have seen the same lame issues since each new model
GM did not do countless days of doing real world long term testing of the C7 Z06 to have claims of serious heat soak.
Hell look at all the venting the C7 Z06 has over the C6 ZR1 which had no real heat soak issues and the LT4 put out a bit less boost (PSI) then the supercharger of C6 ZR1.
GM correctly stated in that heat soak will not be a big issue in real world driving, if racing in hot weather ALL boost engines need more cooler air and most of us solved that by
1. Good hood venting
2. Correct tuning for leaner conditions and best
3. We install a water/methanol injection kit ( used since WW-II in fighter planes) that will reduce IAT a good 40-60 degrees to assure good cold air charge to the cylinders.
As seen below just a few more PCM tables that adjust as IAT (Intake Air Temps) change but again using results from a dyno or a screwed up tune is a dis-service to the Z06 design by GM
Only when it is shown that Z06 owners went to a dealer and seen heat soak issues should the whining begin but before that,
Z06 is a steal in price per its performance ability
Attached Images Attached Images
excerp from JR at the stingray forum
Being the PCM makes adjustments over time, if sitting on some chassis dyno and screwing around for some time there is not going to be the cooler airflow nor since pulls are only couple of minutes the PCM has little chance to make adjustments for hotter air temps and every time the car is turned off and then another pull done then the PCM adjusting has to start over
Add those who are bashing about heat soaking are also screwing with the tune and as such made claims the tune is conservative, hence you know they are jacking up the timing tables and worse not properly tuning other tables for fuel, airmass, knock, misfires, etc, etc and making the problems out of bounds to a correct tune
Since a supercharger is compressing the air that causes the air to get hotter, the more heat the more the air expands which then means there is less molecules per volume which means the cylinder burn is not very good
Add E10 or E10 gas and the total means leaner, hotter, more knock and the PCM as designed to protect the engine will pull timing ( if engine is running longer enough for that drive cycle)
Strapped down on a dyno with no real cooler airflow and the inner cooler for intake cannot do it's job
Add hood left open and pressure is lost so that even the fan for radiator is useless.
The PCM has like 2 meg bytes of content, that means there is countless functions and tables that are used so simple "heat soak" involves many of them and they cannot be properly used in short runs on a chassis dyno
GM protects the engine for the first 500 miles, anyone banging on the LT4 and making claims have zero clue about any of this and are doing BS marketing as the engine broke in and then allowing PCM to fully adapt will have totally different results.
All these functions have existed since the C4 Corvette and we have seen the same lame issues since each new model
GM did not do countless days of doing real world long term testing of the C7 Z06 to have claims of serious heat soak.
Hell look at all the venting the C7 Z06 has over the C6 ZR1 which had no real heat soak issues and the LT4 put out a bit less boost (PSI) then the supercharger of C6 ZR1.
GM correctly stated in that heat soak will not be a big issue in real world driving, if racing in hot weather ALL boost engines need more cooler air and most of us solved that by
1. Good hood venting
2. Correct tuning for leaner conditions and best
3. We install a water/methanol injection kit ( used since WW-II in fighter planes) that will reduce IAT a good 40-60 degrees to assure good cold air charge to the cylinders.
As seen below just a few more PCM tables that adjust as IAT (Intake Air Temps) change but again using results from a dyno or a screwed up tune is a dis-service to the Z06 design by GM
Only when it is shown that Z06 owners went to a dealer and seen heat soak issues should the whining begin but before that,
Z06 is a steal in price per its performance ability
Attached Images Attached Images
excerp from JR at the stingray forum
Burning Brakes
Joined: Dec 2007
Posts: 967
Likes: 6
From: Downers Grove IL
Prove the Corvette under NORMAL real world use is dropping any more performance under temperature or that Dodge or any other nameplate does not pull timing under those conditions ?
Hate to tall you but EVERY car in the USA that has to comply with EPA and smog testing has IAT temp tables that pull timing as temps get higher
People need to learn the basics as when air gets hots and expands, what does it lose ?
and why when cylinder temps are going up that you want to PULL timing to prevent heavy engine knock
Hell most have no clue of how much Ethanol their state/county is mandating nor the different in winter and summer gas and people are whining about some idiots who are abusing LT4s before they are even broken in AND allows the PCM to slant settings AFTER the 500 mile required break in period
Anyone thinking in this cold winter weather that a stock Z06 on the street is overheating or pulling timing due to hot IAT really needs to buy some ricer and leave America's sports car to us real Corvette fans.
You do not strap on a dummy chassis dyno and beat the hell out of the car for bogus bloated dyno queen peak numbers for marketing hype and not know what heat soak is about
Hello boost is compressing AIR which heats it up and their is a inner cooler and no different then a ZR1 which has no real world heat soak issues.
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OK, you have my attention. I admit I am ignorant. Please post more on this as I am truly interested in learning. I am scheduled to close on a Z06 next week...
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Quote Originally Posted by Babaron View Post
OK, you have my attention. I admit I am ignorant. Please post more on this as I am truly interested in learning. I am scheduled to close on a Z06 next week...
It is not about being ignorant but simply people do not understand all that goes on with OBD designed engines, all it's feedback sensors and how the PCM adjust to changing conditions, different modes of operation, the hard rules pushed onto nameplates as to EPA, SMOG, CARB.
Being the PCM makes adjustments over time, if sitting on some chassis dyno and screwing around for some time there is not going to be the cooler airflow nor since pulls are only couple of minutes the PCM has little chance to make adjustments for hotter air temps and every time the car is turned off and then another pull done then the PCM adjusting has to start over
Add those who are bashing about heat soaking are also screwing with the tune and as such made claims the tune is conservative, hence you know they are jacking up the timing tables and worse not properly tuning other tables for fuel, airmass, knock, misfires, etc, etc and making the problems out of bounds to a correct tune
Since a supercharger is compressing the air that causes the air to get hotter, the more heat the more the air expands which then means there is less molecules per volume which means the cylinder burn is not very good
Add E10 or E10 gas and the total means leaner, hotter, more knock and the PCM as designed to protect the engine will pull timing ( if engine is running longer enough for that drive cycle)
Strapped down on a dyno with no real cooler airflow and the inner cooler for intake cannot do it's job
Add hood left open and pressure is lost so that even the fan for radiator is useless.
The PCM has like 2 meg bytes of content, that means there is countless functions and tables that are used so simple "heat soak" involves many of them and they cannot be properly used in short runs on a chassis dyno
GM protects the engine for the first 500 miles, anyone banging on the LT4 and making claims have zero clue about any of this and are doing BS marketing as the engine broke in and then allowing PCM to fully adapt will have totally different results.
All these functions have existed since the C4 Corvette and we have seen the same lame issues since each new model
GM did not do countless days of doing real world long term testing of the C7 Z06 to have claims of serious heat soak.
Hell look at all the venting the C7 Z06 has over the C6 ZR1 which had no real heat soak issues and the LT4 put out a bit less boost (PSI) then the supercharger of C6 ZR1.
GM correctly stated in that heat soak will not be a big issue in real world driving, if racing in hot weather ALL boost engines need more cooler air and most of us solved that by
1. Good hood venting
2. Correct tuning for leaner conditions and best
3. We install a water/methanol injection kit ( used since WW-II in fighter planes) that will reduce IAT a good 40-60 degrees to assure good cold air charge to the cylinders.
As seen below just a few more PCM tables that adjust as IAT (Intake Air Temps) change but again using results from a dyno or a screwed up tune is a dis-service to the Z06 design by GM
Only when it is shown that Z06 owners went to a dealer and seen heat soak issues should the whining begin but before that,
Z06 is a steal in price per its performance ability
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Today, 08:52 PM #25
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Quote Originally Posted by J.R View Post
It is not about being ignorant but simply people do not understand all that goes on with OBD designed engines, all it's feedback sensors and how the PCM adjust to changing conditions, different modes of operation, the hard rules pushed onto nameplates as to EPA, SMOG, CARB.
Being the PCM makes adjustments over time, if sitting on some chassis dyno and screwing around for some time there is not going to be the cooler airflow nor since pulls are only couple of minutes the PCM has little chance to make adjustments for hotter air temps and every time the car is turned off and then another pull done then the PCM adjusting has to start over
Add those who are bashing about heat soaking are also screwing with the tune and as such made claims the tune is conservative, hence you know they are jacking up the timing tables and worse not properly tuning other tables for fuel, airmass, knock, misfires, etc, etc and making the problems out of bounds to a correct tune
Since a supercharger is compressing the air that causes the air to get hotter, the more heat the more the air expands which then means there is less molecules per volume which means the cylinder burn is not very good
Add E10 or E10 gas and the total means leaner, hotter, more knock and the PCM as designed to protect the engine will pull timing ( if engine is running longer enough for that drive cycle)
Strapped down on a dyno with no real cooler airflow and the inner cooler for intake cannot do it's job
Add hood left open and pressure is lost so that even the fan for radiator is useless.
The PCM has like 2 meg bytes of content, that means there is countless functions and tables that are used so simple "heat soak" involves many of them and they cannot be properly used in short runs on a chassis dyno
GM protects the engine for the first 500 miles, anyone banging on the LT4 and making claims have zero clue about any of this and are doing BS marketing as the engine broke in and then allowing PCM to fully adapt will have totally different results.
All these functions have existed since the C4 Corvette and we have seen the same lame issues since each new model
GM did not do countless days of doing real world long term testing of the C7 Z06 to have claims of serious heat soak.
Hell look at all the venting the C7 Z06 has over the C6 ZR1 which had no real heat soak issues and the LT4 put out a bit less boost (PSI) then the supercharger of C6 ZR1.
GM correctly stated in that heat soak will not be a big issue in real world driving, if racing in hot weather ALL boost engines need more cooler air and most of us solved that by
1. Good hood venting
2. Correct tuning for leaner conditions and best
3. We install a water/methanol injection kit ( used since WW-II in fighter planes) that will reduce IAT a good 40-60 degrees to assure good cold air charge to the cylinders.
As seen below just a few more PCM tables that adjust as IAT (Intake Air Temps) change but again using results from a dyno or a screwed up tune is a dis-service to the Z06 design by GM
Only when it is shown that Z06 owners went to a dealer and seen heat soak issues should the whining begin but before that,
Z06 is a steal in price per its performance ability
I think many of us commend you on educating the masses on a subject that you clearly have a great understanding of.
Thank you very much!!
Mike Furman
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Today, 10:24 PM #26
J.R
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Your welcome Mike
I teach an advanced AAS course at a college on all this and I'd say 90% of the students know nothing about how controllers have been in
cars such as the 1984 C4 and all that is being done by the PCM / TCM controllers to have good performance, MPG, EPA and smog
Final exam of my course students must find a engine problem I create, performance tune and then load bearing dyno that will pass smog for their grade and
many just do not grasp all the functions of engines today
Interesting how back in 1980s all this started because of smog rules and how today we can have a Corvette with 450 HP and get 30 MPG
where pre OBD cars lucky to get 10 MPG and had 1/3rd the HP cars have today
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Hate to tall you but EVERY car in the USA that has to comply with EPA and smog testing has IAT temp tables that pull timing as temps get higher
People need to learn the basics as when air gets hots and expands, what does it lose ?
and why when cylinder temps are going up that you want to PULL timing to prevent heavy engine knock
Hell most have no clue of how much Ethanol their state/county is mandating nor the different in winter and summer gas and people are whining about some idiots who are abusing LT4s before they are even broken in AND allows the PCM to slant settings AFTER the 500 mile required break in period
Anyone thinking in this cold winter weather that a stock Z06 on the street is overheating or pulling timing due to hot IAT really needs to buy some ricer and leave America's sports car to us real Corvette fans.
You do not strap on a dummy chassis dyno and beat the hell out of the car for bogus bloated dyno queen peak numbers for marketing hype and not know what heat soak is about
Hello boost is compressing AIR which heats it up and their is a inner cooler and no different then a ZR1 which has no real world heat soak issues.
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Babaron
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OK, you have my attention. I admit I am ignorant. Please post more on this as I am truly interested in learning. I am scheduled to close on a Z06 next week...
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Today, 08:46 PM #24
J.R
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Quote Originally Posted by Babaron View Post
OK, you have my attention. I admit I am ignorant. Please post more on this as I am truly interested in learning. I am scheduled to close on a Z06 next week...
It is not about being ignorant but simply people do not understand all that goes on with OBD designed engines, all it's feedback sensors and how the PCM adjust to changing conditions, different modes of operation, the hard rules pushed onto nameplates as to EPA, SMOG, CARB.
Being the PCM makes adjustments over time, if sitting on some chassis dyno and screwing around for some time there is not going to be the cooler airflow nor since pulls are only couple of minutes the PCM has little chance to make adjustments for hotter air temps and every time the car is turned off and then another pull done then the PCM adjusting has to start over
Add those who are bashing about heat soaking are also screwing with the tune and as such made claims the tune is conservative, hence you know they are jacking up the timing tables and worse not properly tuning other tables for fuel, airmass, knock, misfires, etc, etc and making the problems out of bounds to a correct tune
Since a supercharger is compressing the air that causes the air to get hotter, the more heat the more the air expands which then means there is less molecules per volume which means the cylinder burn is not very good
Add E10 or E10 gas and the total means leaner, hotter, more knock and the PCM as designed to protect the engine will pull timing ( if engine is running longer enough for that drive cycle)
Strapped down on a dyno with no real cooler airflow and the inner cooler for intake cannot do it's job
Add hood left open and pressure is lost so that even the fan for radiator is useless.
The PCM has like 2 meg bytes of content, that means there is countless functions and tables that are used so simple "heat soak" involves many of them and they cannot be properly used in short runs on a chassis dyno
GM protects the engine for the first 500 miles, anyone banging on the LT4 and making claims have zero clue about any of this and are doing BS marketing as the engine broke in and then allowing PCM to fully adapt will have totally different results.
All these functions have existed since the C4 Corvette and we have seen the same lame issues since each new model
GM did not do countless days of doing real world long term testing of the C7 Z06 to have claims of serious heat soak.
Hell look at all the venting the C7 Z06 has over the C6 ZR1 which had no real heat soak issues and the LT4 put out a bit less boost (PSI) then the supercharger of C6 ZR1.
GM correctly stated in that heat soak will not be a big issue in real world driving, if racing in hot weather ALL boost engines need more cooler air and most of us solved that by
1. Good hood venting
2. Correct tuning for leaner conditions and best
3. We install a water/methanol injection kit ( used since WW-II in fighter planes) that will reduce IAT a good 40-60 degrees to assure good cold air charge to the cylinders.
As seen below just a few more PCM tables that adjust as IAT (Intake Air Temps) change but again using results from a dyno or a screwed up tune is a dis-service to the Z06 design by GM
Only when it is shown that Z06 owners went to a dealer and seen heat soak issues should the whining begin but before that,
Z06 is a steal in price per its performance ability
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Mike@Criswell and davem like this.
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Quote Originally Posted by J.R View Post
It is not about being ignorant but simply people do not understand all that goes on with OBD designed engines, all it's feedback sensors and how the PCM adjust to changing conditions, different modes of operation, the hard rules pushed onto nameplates as to EPA, SMOG, CARB.
Being the PCM makes adjustments over time, if sitting on some chassis dyno and screwing around for some time there is not going to be the cooler airflow nor since pulls are only couple of minutes the PCM has little chance to make adjustments for hotter air temps and every time the car is turned off and then another pull done then the PCM adjusting has to start over
Add those who are bashing about heat soaking are also screwing with the tune and as such made claims the tune is conservative, hence you know they are jacking up the timing tables and worse not properly tuning other tables for fuel, airmass, knock, misfires, etc, etc and making the problems out of bounds to a correct tune
Since a supercharger is compressing the air that causes the air to get hotter, the more heat the more the air expands which then means there is less molecules per volume which means the cylinder burn is not very good
Add E10 or E10 gas and the total means leaner, hotter, more knock and the PCM as designed to protect the engine will pull timing ( if engine is running longer enough for that drive cycle)
Strapped down on a dyno with no real cooler airflow and the inner cooler for intake cannot do it's job
Add hood left open and pressure is lost so that even the fan for radiator is useless.
The PCM has like 2 meg bytes of content, that means there is countless functions and tables that are used so simple "heat soak" involves many of them and they cannot be properly used in short runs on a chassis dyno
GM protects the engine for the first 500 miles, anyone banging on the LT4 and making claims have zero clue about any of this and are doing BS marketing as the engine broke in and then allowing PCM to fully adapt will have totally different results.
All these functions have existed since the C4 Corvette and we have seen the same lame issues since each new model
GM did not do countless days of doing real world long term testing of the C7 Z06 to have claims of serious heat soak.
Hell look at all the venting the C7 Z06 has over the C6 ZR1 which had no real heat soak issues and the LT4 put out a bit less boost (PSI) then the supercharger of C6 ZR1.
GM correctly stated in that heat soak will not be a big issue in real world driving, if racing in hot weather ALL boost engines need more cooler air and most of us solved that by
1. Good hood venting
2. Correct tuning for leaner conditions and best
3. We install a water/methanol injection kit ( used since WW-II in fighter planes) that will reduce IAT a good 40-60 degrees to assure good cold air charge to the cylinders.
As seen below just a few more PCM tables that adjust as IAT (Intake Air Temps) change but again using results from a dyno or a screwed up tune is a dis-service to the Z06 design by GM
Only when it is shown that Z06 owners went to a dealer and seen heat soak issues should the whining begin but before that,
Z06 is a steal in price per its performance ability
I think many of us commend you on educating the masses on a subject that you clearly have a great understanding of.
Thank you very much!!
Mike Furman
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Mike Furman
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Criswell Chevrolet
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Today, 10:24 PM #26
J.R
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Your welcome Mike
I teach an advanced AAS course at a college on all this and I'd say 90% of the students know nothing about how controllers have been in
cars such as the 1984 C4 and all that is being done by the PCM / TCM controllers to have good performance, MPG, EPA and smog
Final exam of my course students must find a engine problem I create, performance tune and then load bearing dyno that will pass smog for their grade and
many just do not grasp all the functions of engines today
Interesting how back in 1980s all this started because of smog rules and how today we can have a Corvette with 450 HP and get 30 MPG
where pre OBD cars lucky to get 10 MPG and had 1/3rd the HP cars have today
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Drifting
Joined: Aug 2014
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They will iron it out, its all over reaction.... and i love everyone's second hand opinion on the car, there are really people coming on here to complain about a car they DONT own or even plan too own.. i just dont get it
My Z06 had orange peel when i bought it 6 years ago, i didn't complain about it, i just dealt with it.... if i wanted something flawless i would have spent 150-200k and bought a ferrari...
My Z06 had orange peel when i bought it 6 years ago, i didn't complain about it, i just dealt with it.... if i wanted something flawless i would have spent 150-200k and bought a ferrari...
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Agreed. I have a feeling these cars will loosen after the break in period. This was hotly debated (because that's what car guys do other than driving) when the ZL1 came out. Chevy was very intent on having the owners follow the break in even though some owners insisted on beating the crap out of the car from mile one. It got so bad one of the Camaro team members would repeatedly post. He also recommended to disconnect the battery right after the break in was completed and then let it fly (not his exact words). Below is one of his many posts.