Fuel Milage Question?
02-14-2010, 08:48 AM
#21
People who say they are getting 30+ mpg out of a GTO are more then likely full of crap. I've owned 3, and for some weird reason my 04's got worst gas mileage then my 06. I've driven at a 60 mph and gotten 24 mpg and that was an all highway stretch for about 30 miles in my one of my 04's. I typically got 13-14 mpg in the city with the '04's and I get 15-17 with the '06. Doing bolt-ons, like a CAI or cat-back do not effect mpg in any significant amount.
When I swapped heads, I couldn't do it anymore. Best was 27mpg. When I swapped to a Comp 228/232 cam, best was 25mpg. Then swapped to a FTI 220/224 cam, back up to 27mpg. All having to retune lean cruise to get the best results. Without lean cruise, its 2-3mpg worse.
If you can't get the mileage, you need someone to help tune it for you. My experience is just with my '04. My parent's have an '05 and I think the best they got was 25mpg going from VA to FL. But you can't do lean cruise on a LS2, so it is what it is.
02-14-2010, 10:49 AM
#23
Lean cruise is basically illegal to do. That's why you can't do it on anything other than the '04 GTO. The code was not left out like it is in the US. They just updated the Holden programming for over here but left the code in but it wasn't used.
I wanted lean cruise because my TTA could have it enabled and it worked great on that car. So in '04, I searched on how to do it. On the HPT forum, they would lock any thread on lean cruise because it was illegal. I then went to the Ausi forums to figure out how it worked. I tried it originally back in late '04 and have been using it ever since. Once others had tried it, they saw the gains in mpg as well.
It's been said that the cats will end up being killed but I haven't any problems with mine. If you log your car, you'll see the O2's park around 30mv instead of swinging up and down. But every once in awhile the O2's will show a really rich condition and then go back. I think that's to cool the cats but not sure.
I wanted lean cruise because my TTA could have it enabled and it worked great on that car. So in '04, I searched on how to do it. On the HPT forum, they would lock any thread on lean cruise because it was illegal. I then went to the Ausi forums to figure out how it worked. I tried it originally back in late '04 and have been using it ever since. Once others had tried it, they saw the gains in mpg as well.
It's been said that the cats will end up being killed but I haven't any problems with mine. If you log your car, you'll see the O2's park around 30mv instead of swinging up and down. But every once in awhile the O2's will show a really rich condition and then go back. I think that's to cool the cats but not sure.
02-14-2010, 11:06 AM
#24
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Lean cruise is basically illegal to do. That's why you can't do it on anything other than the '04 GTO. The code was not left out like it is in the US. They just updated the Holden programming for over here but left the code in but it wasn't used.
I wanted lean cruise because my TTA could have it enabled and it worked great on that car. So in '04, I searched on how to do it. On the HPT forum, they would lock any thread on lean cruise because it was illegal. I then went to the Ausi forums to figure out how it worked. I tried it originally back in late '04 and have been using it ever since. Once others had tried it, they saw the gains in mpg as well.
It's been said that the cats will end up being killed but I haven't any problems with mine. If you log your car, you'll see the O2's park around 30mv instead of swinging up and down. But every once in awhile the O2's will show a really rich condition and then go back. I think that's to cool the cats but not sure.
I wanted lean cruise because my TTA could have it enabled and it worked great on that car. So in '04, I searched on how to do it. On the HPT forum, they would lock any thread on lean cruise because it was illegal. I then went to the Ausi forums to figure out how it worked. I tried it originally back in late '04 and have been using it ever since. Once others had tried it, they saw the gains in mpg as well.
It's been said that the cats will end up being killed but I haven't any problems with mine. If you log your car, you'll see the O2's park around 30mv instead of swinging up and down. But every once in awhile the O2's will show a really rich condition and then go back. I think that's to cool the cats but not sure.
02-14-2010, 12:25 PM
#25
EPA doesn't like it because of emissions. It has no effect on WOT or part throttle driving. Pretty much steady state cruising, hence the name
02-14-2010, 02:55 PM
#26
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02-14-2010, 03:35 PM
#27
You could run in open loop and set your afr lean when in those cells for cruising using a wide band. Or they could do some form of psuedo lean cruise but that is pretty complicated and I wouldn't know how to do it.
Most tuners don't do anything other than WOT. You really have to do some research to find a really good one.
02-14-2010, 03:40 PM
#28
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There is nothing in HPT that will "turn" on lean cruise with the LS2 as I don't even think its in the code anymore.
You could run in open loop and set your afr lean when in those cells for cruising using a wide band. Or they could do some form of psuedo lean cruise but that is pretty complicated and I wouldn't know how to do it.
Most tuners don't do anything other than WOT. You really have to do some research to find a really good one.
You could run in open loop and set your afr lean when in those cells for cruising using a wide band. Or they could do some form of psuedo lean cruise but that is pretty complicated and I wouldn't know how to do it.
Most tuners don't do anything other than WOT. You really have to do some research to find a really good one.
