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Do you want DOD/AFM to come on the Camaro?

  • Yes

    Votes: 28 84.8%
  • No

    Votes: 5 15.2%
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Discussion Starter · #3 ·
I must have missed it if we did.

Something I am wondering is why would you not want it on the car?
 

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Well, actually the L76 will be used in some 1/2-ton trucks.

I dunno about AFM causing a horsepower loss, I've yet to see any factual info to back that up.

I agree with Brandon... why wouldn't you want it?
Zero performance loss, zero audible effect, zero extra cost, and more MPG.
Gimme. :)
 

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I dont see how it could lose 20 hp or any for that matter. That guy must be thinking parasitic mechanical loss from more components, which still isnt warranted with modern DOD/AFM. From my understanding the DOD/AFM is mostly electronic not mechanical.
The first DOD technology, to deactivate a cylinder, the exhaust valve is kept from opening after the power stroke and the exhaust gas charge is held in the cylinder and compressed during the exhaust stroke. After the exhaust stroke, the intake valve is kept from opening. The exhaust gas in the cylinder is expanded and compressed over and over again and acts like a gas spring or shock. As multiple cylinders are shut off at a time (cyl. 1, 4, 6 and 7 for a V8), the power required for compression of the exhaust gas in one cylinder is matched by the decompression of imprisoned exhaust gas in another cylinder. When someone needed to kick ass on the green light, the exhaust valve is reactivated and the old exhaust gas released during the exhaust stroke. The intake valve is also reactivated and traditional engine operation begin. GM was the first to use existing production engines with this system with the introduction of the Cadillac L62 V8-6-4 in 1981. With that system I can see parasitic mechanical loss.
The electronics side was improved with Electronic Throttle Control, electronically controlled trannys, transient engine and transmission controls, engine emissions controls, and vastly increased computing power. A solenoid control valve assembly in the engine valley cover contains valves that provide a pressurized oil signal to specially designed hydraulic roller lifters provided by Eaton Corp. and Delphi. These lifters disable and enable exhaust and intake valve operation to deactivate and reactivate engine cylinders. Unlike the original system, only half of the cylinders can be shut off. This system uses engine oil to hydraulically control engine valve function. GM used this second system (now called Active Fuel Management) to be available on 2005 Envoy XL, Envoy XUV and TrailBlazer EXT using optional Vortec 5300 V8. GM also used AFM on the LZ8 V6 in the Impala and Monte Carlo.

Im in favor DOD/AFM if it can be retained after a tune after mods. I dont see it being a issue though, as long as tuners/shops dont get lazy and delete the function or refuse to work around it.
 

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Discussion Starter · #9 ·
Another thing is if you do not want it on your car it would be very easy for you to find a friend with tuning software and buy the credits or buy the software yourself and disable it. That would be cheaper than it not coming on the car factory because of the gas guzzler tax.

The current CTSV has a $1300 gas guzzler tax. Lets say the current CTSV had it. Wouldn't that make it fall into the NO TAX bracket? That is more than enough to buy the software to disable it if for some unknown reason you wanted to.
Cadillac CTSV
Gas guzzler tax (R8E)

Here is how the gas guzzler tax is:
http://www.fueleconomy.gov/feg/info.shtml#guzzler

GAS GUZZLER TAX
Unadjusted MPG (combined)* Tax
at least 22.5 No tax
at least 21.5, but less than 22.5 $1000
at least 20.5, but less than 21.5 $1300
at least 19.5, but less than 20.5 $1700
at least 18.5, but less than 19.5 $2100
at least 17.5, but less than 18.5 $2600
at least 16.5, but less than 17.5 $3000
at least 15.5, but less than 16.5 $3700
at least 14.5, but less than 15.5 $4500
at least 13.5, but less than 14.5 $5400
at least 12.5, but less than 13.5 $6400
less than 12.5 $7700

The combined fuel economy MPG value (55% city, 45% highway) is used to determine tax liability.
 

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I dont see how it could lose 20 hp or any for that matter. That guy must be thinking parasitic mechanical loss from more components, which still isnt warranted with modern DOD/AFM. From my understanding the DOD/AFM is mostly electronic not mechanical.
The first DOD technology, to deactivate a cylinder, the exhaust valve is kept from opening after the power stroke and the exhaust gas charge is held in the cylinder and compressed during the exhaust stroke. After the exhaust stroke, the intake valve is kept from opening. The exhaust gas in the cylinder is expanded and compressed over and over again and acts like a gas spring or shock. As multiple cylinders are shut off at a time (cyl. 1, 4, 6 and 7 for a V8), the power required for compression of the exhaust gas in one cylinder is matched by the decompression of imprisoned exhaust gas in another cylinder. When someone needed to kick ass on the green light, the exhaust valve is reactivated and the old exhaust gas released during the exhaust stroke. The intake valve is also reactivated and traditional engine operation begin. GM was the first to use existing production engines with this system with the introduction of the Cadillac L62 V8-6-4 in 1981. With that system I can see parasitic mechanical loss.
The electronics side was improved with Electronic Throttle Control, electronically controlled trannys, transient engine and transmission controls, engine emissions controls, and vastly increased computing power. A solenoid control valve assembly in the engine valley cover contains valves that provide a pressurized oil signal to specially designed hydraulic roller lifters provided by Eaton Corp. and Delphi. These lifters disable and enable exhaust and intake valve operation to deactivate and reactivate engine cylinders. Unlike the original system, only half of the cylinders can be shut off. This system uses engine oil to hydraulically control engine valve function. GM used this second system (now called Active Fuel Management) to be available on 2005 Envoy XL, Envoy XUV and TrailBlazer EXT using optional Vortec 5300 V8. GM also used AFM on the LZ8 V6 in the Impala and Monte Carlo.

Im in favor DOD/AFM if it can be retained after a tune after mods. I dont see it being a issue though, as long as tuners/shops dont get lazy and delete the function or refuse to work around it.
:lol:
 

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this is pretty new to me. so someone thinks the new g8 is robbed of 20hp due to a computer restriction??? explain this, never heard of this except that the caddy's can shut 4 cylinders off and the camaro may be able to do the same. thats all i heard.
 

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Discussion Starter · #12 ·
this is pretty new to me. so someone thinks the new g8 is robbed of 20hp due to a computer restriction??? explain this, never heard of this except that the caddy's can shut 4 cylinders off and the camaro may be able to do the same. thats all i heard.
There really shouldn't be any HP loss from the new system.

I asked this quetion just to see if anyone had any comments on it on the HPT forum.
http://www.hptuners.com/forum/showthread.php?t=13904

also check this page out:
http://www.pickuptruck.com/html/stories/gmctech/three3.html
 

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this is pretty new to me. so someone thinks the new g8 is robbed of 20hp due to a computer restriction??? explain this, never heard of this except that the caddy's can shut 4 cylinders off and the camaro may be able to do the same. thats all i heard.
With the new system made in the recent decade shouldnt have any power loss. I think it more like lower compression (vs.LS2), lower octane tune, and prolly a milder cam spec, to contribute to a lower Hp vs LS2.
 

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Discussion Starter · #15 ·
With the new system made in the recent decade shouldnt have any power loss. I think it more like lower compression (vs.LS2), lower octane tune, and prolly a milder cam spec, to contribute to a lower Hp vs LS2.
I agree
 

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From my searching for info on the L76, my understanding is that the cam profile is milder to the LS2 cam, although I cant find the spec on the L76 cam. But I imagine a slightly more aggressive cam, milling the head, and 93 octane tune will net more than a LS2. Just a guess. I hate for an engine with identical displacement with better flowing heads not to have higher potential (vs. LS2)
 

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