Promising better fuel economy for AFM engines, the Range

[j-ten-ner]

dont know how the new 4.3l will hold in afm then.

 

 

Maybe even better than the V8. The V6 shuts down only 2 cylinder.

Or better; the V6 has only 2 cylinder slopping around in V4 mode.

 

so long

j-ten-ner

[rt66er]

Gearing has a significant effect on AFM implementation as well. I know that my 08 Sierra with 4-speed auto and 3.73 gear would stay in 4-cylinder mode longer and more often than my 11 Sierra with 6-speed auto and 3.23 gear, as the shorter-geared 08 would be running a bit closer to it's torque peak (about an extra 300 rpm) at highway cruising speeds (60-70 mph).

[Knowklew]

So any update to this....just curious

[Range Technology]

Quick update from an engineering standpoint ... we are well into testing the V8 only mode module. Looks like it's working great so far! About 375+ miles so far of all sorts of driving (and Megabtyes of logs to comb through ) and all is well. Stays totally in V8 with no hiccups! This is a 5.3 2011 Silverado 4WD with the 6 speed. Sending out some test modules for our beta fleet to run up on 6.2s and SUV platforms to make sure there aren't any surprises there.

 

We'll be working with the product/marketing folks this week to see next steps! Hopefully in the upcoming weeks we will see this go to production as a companion product, as long as no snags occur!

 

Also, another idea in the pipeline regarding an alternate calibration for people who spend a lot of time at high speeds, but have to see what the product folks think…

[Tucker]

Great News on the V8 only testing please keep us posted on the progress. What I hate about the V4 mode is the constant in and out shifting at or below 35 MPH in town driving. Where I live it is hilly terrain and it cannot hold V4. I usually just use M5 but trying to explain to my wife about using M5 to stop the hesitation that U get. "She just says I am not fooling with that. Why don't this truck drive right?" I really wish GM had designed AFM to kick in above 45MPH. But in the end I would prefer to just turn AFM off. I really don't want to buy a performance tuner just to turn it off. Plus turning it off might avoid oil consumption problems down the road if that is still a problem on the 2012's.

[snow man]

I for one am a fan of AFM and I am excited by this product. I was going to buy one if the project Sierra truck had good results... I also wonder if the people at range did any testing of the range wile running e85?

[CKNSLS]

It would be great to run V8 only around town and then unplug it for the highway and let the AFM do it's thing.

[snow man]

AFM doesn't activate under 35mph, at high RPM or at mostly open throttle. While driving around town your always in v8 mode. Personally I would like it if my truck would switch to 4 at stoplights. Why idle 8?

 

[Tucker]

Mine will go into V4 coasting downhill at 20 mph.In the town that I live there is a 12 block strip with red lights. If U run just under that 25 mph U can usually go thru this section without stopping. But the truck is constantly going in and out of V4 because U have to coast at times and when U get back on the gas it stutters for a couple seconds before it kicks into V8.

[Range Technology]

I for one am a fan of AFM and I am excited by this product. I was going to buy one if the project Sierra truck had good results... I also wonder if the people at range did any testing of the range wile running e85?

 

 

Yup and it actually did slightly better because the high octane allowed a touch more timing and resistance to knock.

 

It would be great to run V8 only around town and then unplug it for the highway and let the AFM do it's thing.

 

 

Yep!

AFM doesn't activate under 35mph, at high RPM or at mostly open throttle. While driving around town your always in v8 mode. Personally I would like it if my truck would switch to 4 at stoplights. Why idle 8?

 

 

Actually it will activate as low as 20 mph with a low enough load. Top rpm is about 3000 rpm. As far as idling in v4, its pretty rough and the ECU won't let us keep it there very long (probably to keep the cats hot) so we don't enable our algorithm until 20 mph.

[snow man]

Thanks for the info. I don't recall mine going into 4 at anything below 30 or so. But I guess I also never really looked for it at those speeds either. It also makes sense to keep the cats hot.

[snow man]

Mine will go into V4 coasting downhill at 20 mph.In the town that I live there is a 12 block strip with red lights. If U run just under that 25 mph U can usually go thru this section without stopping. But the truck is constantly going in and out of V4 because U have to coast at times and when U get back on the gas it stutters for a couple seconds before it kicks into V8.

 

why does your truck shutter during transition? My truck shifts in and out seamlessly. If I don't really pay attention I would never know if I'm in 4 or 8.

[Tucker]

It is the worst when I ease into the gas after coasting when I am keeping up with the flow of traffic in town. When I get out of town on the country roads to my house running 35-50 mph it really is pretty seamless, I usually don't notice it at all. Highway is smooth as well.I usually just use M5 but my wife has noticed it . She is the one that brought it up wanting to know if there was something wrong with the truck. For me if the" Range" folks come up with something to cut it off or lock it out below 40-45 mph I would be interested. I guess I have the perfect situation for the hesitation with the speeds I usually have to run around town with the hilly terrain we live in.

[snow man]

Any updates on project Sierra yet? It has been a while since we've heard anything.

[snow man]

This is a little off topic but I've been wondering what kind of mileage do these trucks get while in 4 cylinder mode. I understand there are about a thousand factors that affect this. But as my truck has no DIC I have no instant mileage gizmo. And I'm just looking for a ballpark figure.