range afm device
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Joined: Sep 2015
Posts: 82
Likes: 11
From: yreka ca.
range afm device
I see on the v7 fourm that alot of you are using range afm device. do they really improve the performance in any way. if so what. they say increase of 40-60 more hp.I have 2014 stingray z51 pkg. auto trans.
Racer
Joined: Jan 2020
Posts: 470
Likes: 276
From: So. Maine
The range device does not increase horsepower. It stops the 8 speed transmission from going into active fuel management mode which is what AFM stands for . Your 2014 has a 6 speed transmission.
Team Owner
Joined: Sep 2001
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From: Athens AL
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It doesn't do **** for adding HP/TQ, its to keep the car from dropping from V8 mode to V4 mode which causes its own issues with the A8.
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No performance benefit, but it stops both the A6 and A8 transmission from going into the V4 mode, keeping the car in V8 mode all the time. I have it on my 2014.
Melting Slicks
Joined: Feb 2018
Posts: 2,199
Likes: 1,057
From: North Texas
I believe that your confusing the Range device to the Diablo I3 tuner.
Many people here use a I3 to turn off the AFM.
An aded bonus to this tuner is that you can have a slight increase in performance by using the units 'canned' tunes that it has.
Many people here use a I3 to turn off the AFM.
An aded bonus to this tuner is that you can have a slight increase in performance by using the units 'canned' tunes that it has.
Racer
Joined: Jul 2019
Posts: 444
Likes: 92
From: Truckee, CA
I agree with all of the previous posts but I think this hasn't been mentioned yet. When your car is in 4 cyl mode and you want to accelerate quickly, for example to pass a car, it takes too much time for the car to switch from 4 cyl to 8 cyl mode. The lag was unsafe and gave me anxiety so I got a Range to solve that problem. I've read that it can decrease mileage by about 1 mpg.
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Safety Car
Joined: Nov 2000
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From: SIOUX FALLS SD
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I purchased the range device a couple days after I purchased my C7. There are other devices out there that do the same thing for half the cost however I went with the range. Definitely make this one of your first "mods."
Le Mans Master
Joined: Feb 2010
Posts: 7,798
Likes: 314
From: Santa Fe Tx
Performance is defined by the individual. I have a range device in my 2017GS for the following reasons:
1. I bought a Corvette 8cyl to be a 8cyl.
2. **** gas mileage in a Corvette- however Corvettes do get pretty good mileage with out the afm
3. As a limited IQ Engineer I like simple mechanical systems, I like simple Electronic systems, I like simple
4. Shifting from 8 to 4 and back seemed to create some issues with the A8 transmission which has its own issues so not shift from 4 to 8 or 8 to 4 seems to help the transmission function better
5. drive ability = personally I like not having the so called smoth transition from 8 to 4 and back.
The afm system is extremely complex- it even includes back pressure valves on the exhuast, special lifters for the valves, and about 4000 sensors feeding a computer to make it all work together. The range device basically shift the system down, however, it does not get rid of the special mechanical componets.
just my thoughts after have 2 c-7s with and without a range device.
1. I bought a Corvette 8cyl to be a 8cyl.
2. **** gas mileage in a Corvette- however Corvettes do get pretty good mileage with out the afm
3. As a limited IQ Engineer I like simple mechanical systems, I like simple Electronic systems, I like simple
4. Shifting from 8 to 4 and back seemed to create some issues with the A8 transmission which has its own issues so not shift from 4 to 8 or 8 to 4 seems to help the transmission function better
5. drive ability = personally I like not having the so called smoth transition from 8 to 4 and back.
The afm system is extremely complex- it even includes back pressure valves on the exhuast, special lifters for the valves, and about 4000 sensors feeding a computer to make it all work together. The range device basically shift the system down, however, it does not get rid of the special mechanical componets.
just my thoughts after have 2 c-7s with and without a range device.
Team Owner
Joined: Jul 2004
Posts: 28,502
Likes: 3,302
From: Hartford WI
I agree with all of the previous posts but I think this hasn't been mentioned yet. When your car is in 4 cyl mode and you want to accelerate quickly, for example to pass a car, it takes too much time for the car to switch from 4 cyl to 8 cyl mode. The lag was unsafe and gave me anxiety so I got a Range to solve that problem. I've read that it can decrease mileage by about 1 mpg.
Team Owner
Joined: Jul 2004
Posts: 28,502
Likes: 3,302
From: Hartford WI
I don't think Range or the Diablo tuning I am using will guarantee that the lifters won't fail. From what I understand, they are of a crappy design and/or manufacture so....l
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Joined: Dec 2017
Posts: 3,518
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From: Columbus Ohio
Performance is defined by the individual. I have a range device in my 2017GS for the following reasons:
1. I bought a Corvette 8cyl to be a 8cyl.
2. **** gas mileage in a Corvette- however Corvettes do get pretty good mileage with out the afm
3. As a limited IQ Engineer I like simple mechanical systems, I like simple Electronic systems, I like simple
4. Shifting from 8 to 4 and back seemed to create some issues with the A8 transmission which has its own issues so not shift from 4 to 8 or 8 to 4 seems to help the transmission function better
5. drive ability = personally I like not having the so called smoth transition from 8 to 4 and back.
The afm system is extremely complex- it even includes back pressure valves on the exhuast, special lifters for the valves, and about 4000 sensors feeding a computer to make it all work together. The range device basically shift the system down, however, it does not get rid of the special mechanical componets.
just my thoughts after have 2 c-7s with and without a range device.
1. I bought a Corvette 8cyl to be a 8cyl.
2. **** gas mileage in a Corvette- however Corvettes do get pretty good mileage with out the afm
3. As a limited IQ Engineer I like simple mechanical systems, I like simple Electronic systems, I like simple
4. Shifting from 8 to 4 and back seemed to create some issues with the A8 transmission which has its own issues so not shift from 4 to 8 or 8 to 4 seems to help the transmission function better
5. drive ability = personally I like not having the so called smoth transition from 8 to 4 and back.
The afm system is extremely complex- it even includes back pressure valves on the exhuast, special lifters for the valves, and about 4000 sensors feeding a computer to make it all work together. The range device basically shift the system down, however, it does not get rid of the special mechanical componets.
just my thoughts after have 2 c-7s with and without a range device.
Melting Slicks
Joined: Feb 2018
Posts: 2,199
Likes: 1,057
From: North Texas
So if your engine never does this V8 to V4 to V8 'dance' you stand less of a chance of having a AFM failure.
Team Owner
Joined: Jul 2004
Posts: 28,502
Likes: 3,302
From: Hartford WI
I have to admit, that is the first time I have heard of it. Is it a healthy lifter failing and fails when it switches or is it a lifter going south and happens to fail during the switch? I noticed my A8 has that V8 to V4 mode.