Eco Mode on 7 Speed manual
08-06-2019, 12:02 AM
#21
E-Ray, 3LZ, ZER, LIFT
Member Since: Sep 2007
Location: NE South Carolina
Posts: 29,583
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What are you worrying about wearing? Why only trackers when they are driving on the street? What about forks with an automatic that drive like old grandmothers and are mostly in that mode?
Keep in mind that the valves close at a very controlled time right after a combustion even IN THAT CYLINDER. That keeps cylinder pressure in the cylinder so pistion loads and ring loads remain similar. It does always revert to 8 cylinder mode every ~10 minutes for a short time. Guess that is to keep the pressure or for something
Are you worrying about: cylinder walls, valve guide wear; valve seat wear, bearing wear?
Boy all this worrying! Glad my M7 Grand Sport has never been in 4 cylinder mode so I can get to sleep!
Last edited by JerryU; 08-06-2019 at 12:06 AM.
08-06-2019, 10:00 AM
#22
Racer
The pistons always rotate. The system cuts off fuel and spark to 4 of the cylinders. I went on a long drive and I used the local roads going out and I jumped on the highway on the way back and used ECO mode. There is a noticeable vibration in the shifter when it's running in 4CYL mode. It annoyed me after a while so I turned it off. I am willing to lose the 3 MPG so I won't be annoyed. I wonder how much quicker a manual car would be if this mode was eliminated. I am assuming that there is extra weight added to balance out the vibration in the drivetrain and that stinks.
08-06-2019, 10:42 AM
#23
Melting Slicks
Track guys beat the crap out of our engines. A typical track day at Sebring I see 6300 rpms about 500 times a day. 10-11 times a lap, 9-10 laps a session, 5 sessions, in Florida heat. This is just a little bit harder on the motor than normal street driving. (Ironically most track guys think I’m very easy on my Z, as it doesn’t run hot)
Add 4 cylinder mode to the same motor. Uneven temps are going to produce uneven wear. Doesn’t eco mode time out after a while? Why is that?
Add 4 cylinder mode to the same motor. Uneven temps are going to produce uneven wear. Doesn’t eco mode time out after a while? Why is that?
08-06-2019, 11:31 AM
#24
E-Ray, 3LZ, ZER, LIFT
Member Since: Sep 2007
Location: NE South Carolina
Posts: 29,583
Received 9,651 Likes
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^^^
Yep as I said in my post and is stated below with more detail it shuts off every 10 minutes for 1 minute. Probably a number of reasons. Although I don't Track I live in the country and have several areas going o town (~20 miles) where I pass long farm fields, no homes and the corn and cotton don't care how fast I go! Hit 6600 rpm in the lower gears and then deaccelerate in gear to Stop signes for a relatively long time compared to trackers! That puts the highest loads on some parts. I recall they had an issue with the LS3 NA engine in my C6 Z51 with piston rings allowing excess oil to pass them! They changed the piston ring angles to counter in later models.
This is probably more info hat you want to digest! Gearheads, like me will find it interesting!
Cylinder Deactivation All that you wanted to know (and more) about the AFM system.
"To provide maximum fuel economy under light load driving conditions, the engine control module (ECM) will command the cylinder deactivation system ON to deactivate engine cylinders 1, 7, 6, and 4, switching to a V4 mode. The engine will operate on 8 cylinders, or V8 mode, during engine starting, engine idling, and medium to heavy throttle applications.
Manifold absolute pressure (MAP) and the conditions listed below determine when cylinder deactivation is enabled.
•Engine has been running for greater than 30 s
•Engine speed is between 700 and 2800 rpm
•Engine oil pressure is between 187–455 kPa (27–66 psi)
•Engine coolant temperature is between 40–129°C (100–264°F)
•Engine oil temperature is between 16–128°C (61–263°F)
•Throttle angle is 6% or less
•Ignition voltage is greater than 11 V
•Transmission is not in first, second, or reverse gear
•Vehicle speed is greater than 25 kph (15.5 mph)
•Brake booster pressure is greater than 42.0 kPa (6 psi)
•Vehicle is not in fuel shut of mode
•Vehicle is not in heater performance mode??
•Vehicle is not in tip in bump acceleration mode??
•Vehicle is not in oil aeration mode??
•Vehicle is not in low range (if equipped)
When cylinder deactivation is commanded, the ECM will determine what cylinder is firing and begin deactivation on the next closest deactivated cylinder in firing order sequence. For example, if cylinder number 1 is on its combustion event when cylinder deactivation is commanded ON, the next cylinder in the firing order sequence that can be deactivated is cylinder number 7. If cylinder number 5 is on its combustion event when cylinder deactivation is commanded ON, then the next cylinder in the firing order sequence that can be deactivated is cylinder number 4.
Cylinder deactivation is accomplished by not allowing the intake and exhaust valves to open on the selected cylinders by using special valve lifters. The deactivation lifters contain spring loaded locking pins that connect the internal pin housing of the lifter to the outer housing.
The pin housing contains the lifter plunger and pushrod seat which interfaces with the pushrod. The outer housing contacts the camshaft lobe through a roller. During V8 mode, when all cylinders are active, the locking pins are pushed outward by spring force, locking the pin housing and outer housing together causing the lifter to function as a normal lifter. When cylinder deactivation is commanded ON, the locking pins are pushed inward with engine oil pressure directed from the valve lifter oil manifold assembly solenoids. When the lifter pin housing is unlocked from the outer housing, the pin housing will remain stationary, while the outer housing will move with the profile of the camshaft lobe, which results in the valve remaining closed. One valve lifter oil manifold assembly solenoid controls both the intake and exhaust valves for each deactivating cylinder. There are 2 distinct oil passages going to each cylinder deactivation lifter bore, one for the hydraulic lash-adjusting feature of the lifter, and one for controlling the locking pins used for cylinder deactivation.
Although both intake and exhaust valve lifters are controlled by the same solenoid in the valve lifter oil manifold assembly, the intake and exhaust valves do not become deactivated at the same time. Cylinder deactivation is timed so that the cylinder is on an intake event. During an intake event, the intake cam lobe is pushing the valve lifter upwards to open the intake valve against the force of the valve spring. The force exerted by the valve spring is acting on the side of the lifter locking pins, preventing them from moving until the intake valve has closed. When the intake valve lifter reaches the base circle of the camshaft lobe, the valve spring force is reduced, allowing the locking pins to move, deactivating the intake valve. However, when cylinder deactivation is commanded ON, the exhaust valve for the deactivated cylinder is in the closed position, allowing the locking pins on the valve lifter to move immediately, and deactivate the exhaust valve.
By deactivating the exhaust valve first, this allows the capture of a burnt air/fuel charge, or exhaust gas charge, in the combustion chamber. The capture of exhaust gases in the combustion chamber will contribute to a reduction in oil consumption, noise and vibration levels, and exhaust emissions when operating in V4 mode cylinder deactivation mode.
During the transition from V8 to V4 mode, the Fuel Injectors will be turned OFF on the deactivated cylinders. To help prevent spark plug fouling, the ignition system secondary voltage or spark is still present across the spark plug electrodes on the deactivated cylinders. If all enabling conditions are met and maintained for cylinder deactivation operation, the ECM calibrations will limit cylinder deactivation to a cycle time of 10 minutes in V4 mode, then return to V8 mode for 1 minute.
Switching between V8 and V4 modes is accomplished in less than 250 milliseconds, making the transitions seamless and transparent to the vehicle operator. The 250 milliseconds includes the time for the ECM to sequence the transitions, the response time for the valve lifter oil manifold assembly solenoids to energize, and the time for the valve lifters to deactivate, all within 2 revolutions of the engine crankshaft.
Valve Lifter Oil Manifold Assembly
The cylinder deactivation system uses an electro-hydraulic actuator device called the valve lifter oil manifold assembly. The valve lifter oil manifold assembly is bolted to the top of the engine valley, below the intake manifold assembly. The valve lifter oil manifold assembly consists of 4 electrically operated normally closed solenoids. Each solenoid controls the application of engine oil pressure to the intake and exhaust valve lifters on the cylinders selected to deactivate. Engine oil pressure is routed to the valve lifter oil manifold assembly from an internal oil passage on the rear of the cylinder block.
All 4 valve lifter oil manifold assembly solenoids are connected in parallel to a fused ignition 1 voltage circuit, supplied by the powertrain relay. The ground or control circuit for each solenoid is connected to a low side driver internal to the engine control module (ECM).
When all enabling conditions are met for cylinder deactivation, the ECM will ground each solenoid control circuit in firing order sequence, allowing current to flow through the solenoid windings. With the coil windings energized, the solenoid valve opens, redirecting engine oil pressure through the valve lifter oil manifold assembly into 8 separate vertical passages in the engine lifter valley. The 8 vertical passages, 2 per cylinder, are connected to the valve lifter bores of the cylinders to be deactivated. When vehicle-operating conditions require a return to V8 mode, the ECM will turn OFF the control circuit for the solenoids, allowing the solenoid valves to close. With the solenoid valves closed, engine oil pressure in the control ports is exhausted through the body of the solenoids into the engine block lifter valley. The housing of the valve lifter oil manifold assembly incorporates several bleeds in the oil passages to purge any air trapped in the valve lifter oil manifold assembly or engine block.
To help control contamination to the hydraulic circuits, a small replaceable oil screen is located in the valve lifter oil manifold assembly oil inlet passage, below the oil pressure sensor. The oil pressure sensor is a 3-wire sensor which provides oil pressure information to the ECM.
During service, use extreme care in keeping the valve lifter oil manifold assembly free of any contamination or foreign material.
Cylinder deactivation may be inhibited for many reasons including the following:
•Engine coolant temperature out of range for cylinder activation
•Engine vacuum out of range
•Brake booster vacuum out of range
•Transmission gear incorrect or shift in progress
•Accelerator pedal out of range or rate of pedal application to fast
•Engine oil pressure and temperature out of range
•Engine speed out of range
•Vehicle speed out of range
•Minimum time in V8 mode not met
•Maximum V4 mode time exceeded
•Decel fuel cutoff is active
•Reduced engine power is active
•Torque management is active
•Catalytic converter over temperature protection is active
•Piston protection is active, knock detected
•Cylinder deactivation solenoid driver circuit faults
Perhaps this description of how cylinder deactivation would be of interest versus what is done with an overhead cam engine. Quoting, “ Cylinder deactivation is accomplished by not allowing the intake and exhaust valves to open on the selected cylinders by using special valve lifters. The deactivation lifters contain spring loaded locking pins that connect the internal pin housing of the lifter to the outer housing.
The pin housing contains the lifter plunger and pushrod seat which interfaces with the pushrod. The outer housing contacts the camshaft lobe through a roller. During V8 mode, when all cylinders are active, the locking pins are pushed outward by spring force, locking the pin housing and outer housing together causing the lifter to function as a normal lifter. When cylinder deactivation is commanded ON, the locking pins are pushed inward with engine oil pressure directed from the valve lifter oil manifold assembly solenoids. When the lifter pin housing is unlocked from the outer housing, the pin housing will remain stationary, while the outer housing will move with the profile of the camshaft lobe, which results in the valve remaining closed.
Although both intake and exhaust valve lifters are controlled by the same solenoid in the valve lifter oil manifold assembly, the intake and exhaust valves do not become deactivated at the same time.
By deactivating the exhaust valve first, this allows the capture of a burnt air/fuel charge, or exhaust gas charge, in the combustion chamber. The capture of exhaust gases in the combustion chamber will contribute to a reduction in oil consumption, noise and vibration levels, and exhaust emissions when operating in V4 mode cylinder deactivation mode.
During the transition from V8 to V4 mode, the Fuel Injectors will be turned OFF on the deactivated cylinders. If all enabling conditions are met and maintained for cylinder deactivation operation, the ECM calibrations will limit cylinder deactivation to a cycle time of 10 minutes in V4 mode, then return to V8 mode for 1 minute.
Switching between V8 and V4 modes is accomplished in less than 250 milliseconds, making the transitions seamless and transparent to the vehicle operator.”
There is a good deal more information about how oil pressure is controlled to activate the lifters, that I left out for simplicity!
Yep as I said in my post and is stated below with more detail it shuts off every 10 minutes for 1 minute. Probably a number of reasons. Although I don't Track I live in the country and have several areas going o town (~20 miles) where I pass long farm fields, no homes and the corn and cotton don't care how fast I go! Hit 6600 rpm in the lower gears and then deaccelerate in gear to Stop signes for a relatively long time compared to trackers! That puts the highest loads on some parts. I recall they had an issue with the LS3 NA engine in my C6 Z51 with piston rings allowing excess oil to pass them! They changed the piston ring angles to counter in later models.
This is probably more info hat you want to digest! Gearheads, like me will find it interesting!
Cylinder Deactivation All that you wanted to know (and more) about the AFM system.
"To provide maximum fuel economy under light load driving conditions, the engine control module (ECM) will command the cylinder deactivation system ON to deactivate engine cylinders 1, 7, 6, and 4, switching to a V4 mode. The engine will operate on 8 cylinders, or V8 mode, during engine starting, engine idling, and medium to heavy throttle applications.
Manifold absolute pressure (MAP) and the conditions listed below determine when cylinder deactivation is enabled.
•Engine has been running for greater than 30 s
•Engine speed is between 700 and 2800 rpm
•Engine oil pressure is between 187–455 kPa (27–66 psi)
•Engine coolant temperature is between 40–129°C (100–264°F)
•Engine oil temperature is between 16–128°C (61–263°F)
•Throttle angle is 6% or less
•Ignition voltage is greater than 11 V
•Transmission is not in first, second, or reverse gear
•Vehicle speed is greater than 25 kph (15.5 mph)
•Brake booster pressure is greater than 42.0 kPa (6 psi)
•Vehicle is not in fuel shut of mode
•Vehicle is not in heater performance mode??
•Vehicle is not in tip in bump acceleration mode??
•Vehicle is not in oil aeration mode??
•Vehicle is not in low range (if equipped)
When cylinder deactivation is commanded, the ECM will determine what cylinder is firing and begin deactivation on the next closest deactivated cylinder in firing order sequence. For example, if cylinder number 1 is on its combustion event when cylinder deactivation is commanded ON, the next cylinder in the firing order sequence that can be deactivated is cylinder number 7. If cylinder number 5 is on its combustion event when cylinder deactivation is commanded ON, then the next cylinder in the firing order sequence that can be deactivated is cylinder number 4.
Cylinder deactivation is accomplished by not allowing the intake and exhaust valves to open on the selected cylinders by using special valve lifters. The deactivation lifters contain spring loaded locking pins that connect the internal pin housing of the lifter to the outer housing.
The pin housing contains the lifter plunger and pushrod seat which interfaces with the pushrod. The outer housing contacts the camshaft lobe through a roller. During V8 mode, when all cylinders are active, the locking pins are pushed outward by spring force, locking the pin housing and outer housing together causing the lifter to function as a normal lifter. When cylinder deactivation is commanded ON, the locking pins are pushed inward with engine oil pressure directed from the valve lifter oil manifold assembly solenoids. When the lifter pin housing is unlocked from the outer housing, the pin housing will remain stationary, while the outer housing will move with the profile of the camshaft lobe, which results in the valve remaining closed. One valve lifter oil manifold assembly solenoid controls both the intake and exhaust valves for each deactivating cylinder. There are 2 distinct oil passages going to each cylinder deactivation lifter bore, one for the hydraulic lash-adjusting feature of the lifter, and one for controlling the locking pins used for cylinder deactivation.
Although both intake and exhaust valve lifters are controlled by the same solenoid in the valve lifter oil manifold assembly, the intake and exhaust valves do not become deactivated at the same time. Cylinder deactivation is timed so that the cylinder is on an intake event. During an intake event, the intake cam lobe is pushing the valve lifter upwards to open the intake valve against the force of the valve spring. The force exerted by the valve spring is acting on the side of the lifter locking pins, preventing them from moving until the intake valve has closed. When the intake valve lifter reaches the base circle of the camshaft lobe, the valve spring force is reduced, allowing the locking pins to move, deactivating the intake valve. However, when cylinder deactivation is commanded ON, the exhaust valve for the deactivated cylinder is in the closed position, allowing the locking pins on the valve lifter to move immediately, and deactivate the exhaust valve.
By deactivating the exhaust valve first, this allows the capture of a burnt air/fuel charge, or exhaust gas charge, in the combustion chamber. The capture of exhaust gases in the combustion chamber will contribute to a reduction in oil consumption, noise and vibration levels, and exhaust emissions when operating in V4 mode cylinder deactivation mode.
During the transition from V8 to V4 mode, the Fuel Injectors will be turned OFF on the deactivated cylinders. To help prevent spark plug fouling, the ignition system secondary voltage or spark is still present across the spark plug electrodes on the deactivated cylinders. If all enabling conditions are met and maintained for cylinder deactivation operation, the ECM calibrations will limit cylinder deactivation to a cycle time of 10 minutes in V4 mode, then return to V8 mode for 1 minute.
Switching between V8 and V4 modes is accomplished in less than 250 milliseconds, making the transitions seamless and transparent to the vehicle operator. The 250 milliseconds includes the time for the ECM to sequence the transitions, the response time for the valve lifter oil manifold assembly solenoids to energize, and the time for the valve lifters to deactivate, all within 2 revolutions of the engine crankshaft.
Valve Lifter Oil Manifold Assembly
The cylinder deactivation system uses an electro-hydraulic actuator device called the valve lifter oil manifold assembly. The valve lifter oil manifold assembly is bolted to the top of the engine valley, below the intake manifold assembly. The valve lifter oil manifold assembly consists of 4 electrically operated normally closed solenoids. Each solenoid controls the application of engine oil pressure to the intake and exhaust valve lifters on the cylinders selected to deactivate. Engine oil pressure is routed to the valve lifter oil manifold assembly from an internal oil passage on the rear of the cylinder block.
All 4 valve lifter oil manifold assembly solenoids are connected in parallel to a fused ignition 1 voltage circuit, supplied by the powertrain relay. The ground or control circuit for each solenoid is connected to a low side driver internal to the engine control module (ECM).
When all enabling conditions are met for cylinder deactivation, the ECM will ground each solenoid control circuit in firing order sequence, allowing current to flow through the solenoid windings. With the coil windings energized, the solenoid valve opens, redirecting engine oil pressure through the valve lifter oil manifold assembly into 8 separate vertical passages in the engine lifter valley. The 8 vertical passages, 2 per cylinder, are connected to the valve lifter bores of the cylinders to be deactivated. When vehicle-operating conditions require a return to V8 mode, the ECM will turn OFF the control circuit for the solenoids, allowing the solenoid valves to close. With the solenoid valves closed, engine oil pressure in the control ports is exhausted through the body of the solenoids into the engine block lifter valley. The housing of the valve lifter oil manifold assembly incorporates several bleeds in the oil passages to purge any air trapped in the valve lifter oil manifold assembly or engine block.
To help control contamination to the hydraulic circuits, a small replaceable oil screen is located in the valve lifter oil manifold assembly oil inlet passage, below the oil pressure sensor. The oil pressure sensor is a 3-wire sensor which provides oil pressure information to the ECM.
During service, use extreme care in keeping the valve lifter oil manifold assembly free of any contamination or foreign material.
Cylinder deactivation may be inhibited for many reasons including the following:
•Engine coolant temperature out of range for cylinder activation
•Engine vacuum out of range
•Brake booster vacuum out of range
•Transmission gear incorrect or shift in progress
•Accelerator pedal out of range or rate of pedal application to fast
•Engine oil pressure and temperature out of range
•Engine speed out of range
•Vehicle speed out of range
•Minimum time in V8 mode not met
•Maximum V4 mode time exceeded
•Decel fuel cutoff is active
•Reduced engine power is active
•Torque management is active
•Catalytic converter over temperature protection is active
•Piston protection is active, knock detected
•Cylinder deactivation solenoid driver circuit faults
Perhaps this description of how cylinder deactivation would be of interest versus what is done with an overhead cam engine. Quoting, “ Cylinder deactivation is accomplished by not allowing the intake and exhaust valves to open on the selected cylinders by using special valve lifters. The deactivation lifters contain spring loaded locking pins that connect the internal pin housing of the lifter to the outer housing.
The pin housing contains the lifter plunger and pushrod seat which interfaces with the pushrod. The outer housing contacts the camshaft lobe through a roller. During V8 mode, when all cylinders are active, the locking pins are pushed outward by spring force, locking the pin housing and outer housing together causing the lifter to function as a normal lifter. When cylinder deactivation is commanded ON, the locking pins are pushed inward with engine oil pressure directed from the valve lifter oil manifold assembly solenoids. When the lifter pin housing is unlocked from the outer housing, the pin housing will remain stationary, while the outer housing will move with the profile of the camshaft lobe, which results in the valve remaining closed.
Although both intake and exhaust valve lifters are controlled by the same solenoid in the valve lifter oil manifold assembly, the intake and exhaust valves do not become deactivated at the same time.
By deactivating the exhaust valve first, this allows the capture of a burnt air/fuel charge, or exhaust gas charge, in the combustion chamber. The capture of exhaust gases in the combustion chamber will contribute to a reduction in oil consumption, noise and vibration levels, and exhaust emissions when operating in V4 mode cylinder deactivation mode.
During the transition from V8 to V4 mode, the Fuel Injectors will be turned OFF on the deactivated cylinders. If all enabling conditions are met and maintained for cylinder deactivation operation, the ECM calibrations will limit cylinder deactivation to a cycle time of 10 minutes in V4 mode, then return to V8 mode for 1 minute.
Switching between V8 and V4 modes is accomplished in less than 250 milliseconds, making the transitions seamless and transparent to the vehicle operator.”
There is a good deal more information about how oil pressure is controlled to activate the lifters, that I left out for simplicity!
Last edited by JerryU; 08-06-2019 at 11:32 AM.
The following 2 users liked this post by JerryU:
ANGST_VA (08-07-2019),
Steves LS6 (08-06-2019)
08-06-2019, 12:03 PM
#25
Melting Slicks
^^^
Yep as I said in my post and is stated below with more detail it shuts off every 10 minutes for 1 minute. Probably a number of reasons. Although I don't Track I live in the country and have several areas going o town (~20 miles) where I pass long farm fields, no homes and the corn and cotton don't care how fast I go! Hit 6600 rpm in the lower gears and then deaccelerate in gear to Stop signes for a relatively long time compared to trackers! That puts the highest loads on some parts. I recall they had an issue with the LS3 NA engine in my C6 Z51 with piston rings allowing excess oil to pass them! They changed the piston ring angles to counter in later models.
This is probably more info hat you want to digest! Gearheads, like me will find it interesting.
making the transitions seamless and transparent to the vehicle operator
Yep as I said in my post and is stated below with more detail it shuts off every 10 minutes for 1 minute. Probably a number of reasons. Although I don't Track I live in the country and have several areas going o town (~20 miles) where I pass long farm fields, no homes and the corn and cotton don't care how fast I go! Hit 6600 rpm in the lower gears and then deaccelerate in gear to Stop signes for a relatively long time compared to trackers! That puts the highest loads on some parts. I recall they had an issue with the LS3 NA engine in my C6 Z51 with piston rings allowing excess oil to pass them! They changed the piston ring angles to counter in later models.
This is probably more info hat you want to digest! Gearheads, like me will find it interesting.
making the transitions seamless and transparent to the vehicle operator
Great stuff, thanks. I'll leave it off
08-06-2019, 12:17 PM
#26
E-Ray, 3LZ, ZER, LIFT
Member Since: Sep 2007
Location: NE South Carolina
Posts: 29,583
Received 9,651 Likes
on
6,649 Posts
Yep, used it a few times on the Interstate with my early 2014 Z51. On the same flat road got ~1 to 2 mpg better mpg. Could feel it go back to 8 cylinder even on a small incline. Since I seldom use Interstate (to many 18 wheeler tire treads, radar detector going off so keep speed at 7 over limit) It does just fine in 7th when I do use it! I never have a need to 6th so am usually in 5th on the way to town and in town traffic,Have never put the Grand Sport in ECO- no need!
08-07-2019, 08:29 AM
#27
Racer
I use it all the time. It pretty much switches between the two modes seamlessly. When running in Eco Mode performance isn't hurt as there is no appreciable lag to switch to V8 mode when you punch the throttle. It becomes less effective from a mpg standpoint when driving in 7th gear on the highway. Any slight rise in the road level will cause the engine to switch to V8 mode so it stays in V8 mode most of the time when running in 7th. I found I get better mpg up to 80 mph by using Eco Mode and 6th gear. As for competing with somebody you can always switch it to one of the other modes as it is just a turn of the dial on the console.
Bill
Bill
Last edited by BradT; 08-07-2019 at 08:32 AM.
08-08-2019, 12:22 PM
#28
Drifting
I use mine on long drives...it's seamless and does improve gas mileage...I also put the exhaust in stealth mode...I've had people ask if this is the new E-Corvette...I just smile.