DOD on an LS1?
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My 98Z M6 got a no-chit 32 mpg on the drive from Houston to Amarillo. That was 55-60 mph, all interstate / 4-lane highway (I45 / 287) the whole way, bone stock.
Last time I drove it, it got about 3.
Last time I drove it, it got about 3.
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210 miles on 7 gallons. Little quick math leads me to believe that, that is 30 mpg. Drove to Sebastien, drove around there for a couple days and drove back to Orlando on half a tank. Thanks for coming
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Uhh.... one question. WHY? My auto can get almost 25 mpg highway. My thought is, why buy a car like this and worry about mileage. It's meant to have fun with, and personally, me having fun with it is killing as many fossils as I can.
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I'd go DOD if it were:
-Reliable!
-Just as powerful
-Hardly more money
-Quick to switch from 4/6 cylinders back to 8 when I need it. I don't want to feel a lag.
-At least 5% more fuel efficient
-Reliable!
-Just as powerful
-Hardly more money
-Quick to switch from 4/6 cylinders back to 8 when I need it. I don't want to feel a lag.
-At least 5% more fuel efficient
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For the peole that are doubting the M6 MPG claims, look at it this way: your A4 overdrive is .75 or so; that is what the M6 is in 5th gear, in 6th the overdrive is .50 With the stock rear gears, cruising at 60MPH the motor's only turning what, 1500 RPMs or so?
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why do people ask "why improve"?
Stupidest reasoning ever. in the next 100 years when our great great great grand children are driving around in 800hp 150 mile to the gallon street machines, they are going to find threads like these in the archives with people saying "my car gets 30mpg, why try to improve on that. i think thats pretty efficient"
I bet 15 miles per gallon seemed pretty damn efficient in the 1960's compared to the cars from the 40-50's. imagine if those guys said, why improve? 15mpg is pretty efficient...
Stupidest reasoning ever. in the next 100 years when our great great great grand children are driving around in 800hp 150 mile to the gallon street machines, they are going to find threads like these in the archives with people saying "my car gets 30mpg, why try to improve on that. i think thats pretty efficient"
I bet 15 miles per gallon seemed pretty damn efficient in the 1960's compared to the cars from the 40-50's. imagine if those guys said, why improve? 15mpg is pretty efficient...
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Why are people ruining this thread by turning it into a "is it worth it" thread? I dont care if its worth it or saves any gas at all....Im much more curious to see if someone has the technical know-how and the skill to actually pull it off.
Im curious to see if someone can take the latest and greatest technology and incorporate it into our cars. Hell, its probobly not "worth it" to make your car run on ground up monkeys guts instead of gasoline.....but if you pulled something like that off I would definitley be interested in reading about it.
Lets stop worrying about weather or not its worth it and see if it can actually be done. Cause if it cant be done it's not worth sitting here and debating the merits of it because if its not possible in the first place....and in that case debating the value of doing it makes about as much sense and trying to find out if its worth it to try and pedal your bicycle to the moon.
So, first things first...is it possible?
Im curious to see if someone can take the latest and greatest technology and incorporate it into our cars. Hell, its probobly not "worth it" to make your car run on ground up monkeys guts instead of gasoline.....but if you pulled something like that off I would definitley be interested in reading about it.
Lets stop worrying about weather or not its worth it and see if it can actually be done. Cause if it cant be done it's not worth sitting here and debating the merits of it because if its not possible in the first place....and in that case debating the value of doing it makes about as much sense and trying to find out if its worth it to try and pedal your bicycle to the moon.
So, first things first...is it possible?
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I dont think it would be entirely too hard, if some one was really good at programming.. you would have to build like a piggy back device/program for the pcm that would work as kind of a "limp mode" that would be activated under light acceleration/cruising and basically just shut off the fuel injectors, and ignition supply for say cylinders 1, 2, 7, 8, because 3, 4, 5, 6 are companion cylinders, and would run much like a four cylinder. about shutting the cylinders down completely, i dont think there would really be a way to do that without completely re-engineering the engine.. but by shutting the fuel down, i bet you could still save some gas.
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If GM could have done DOD on the LS1/GenIII purely using injector shutdown without changing the block, designing new DOD lifters and electro mechanical controls as they did for the GenIV, they would have.
Interesting thing about DOD is that when in operation, it leaves the valves closed on the DOD cylinders. This has been proven to be the most efficient/optimal. The remaining 4 cylinders work harder, but become slightly more efficient - the mpg saving being a mix of this efficiency and the reduction in fuel to the DOD cylinders.
The real gains will be once they introduce direct injection. More power, more mpg.
Interesting thing about DOD is that when in operation, it leaves the valves closed on the DOD cylinders. This has been proven to be the most efficient/optimal. The remaining 4 cylinders work harder, but become slightly more efficient - the mpg saving being a mix of this efficiency and the reduction in fuel to the DOD cylinders.
The real gains will be once they introduce direct injection. More power, more mpg.
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30 mpg people, did you all fail math class? post your milage at fill up, then go to same pump and refill and show us the numbers! none of you can do it can you. your just web blowhards claiming glorious things! put up or shut up!
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And dan, it's not really uncommon for an LS1 car to get near to and touch the 30mpg mark if it's a 6-speed. I had a 6-speed LT1 that would touch 30mpg when driven appropriately.
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Simple math:
A4 - 2.73:1 gears x .75 overdrive = 2.0475 final drive ratio
M6 - 3.42:1 gears x .50 overdrive = 1.71 final drive ratio
Or is that too hard to comprehend?
A4 - 2.73:1 gears x .75 overdrive = 2.0475 final drive ratio
M6 - 3.42:1 gears x .50 overdrive = 1.71 final drive ratio
Or is that too hard to comprehend?
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To the OP,
It seems to me that you could get much better gains in FE if you did some simple free mods:
1. Drive smart. Don't floor it. Keep the revs as low as possible (shift around 2500 RPM or lower). Drive around 60-65 in the interstate. etc. Studies have show that mood and style of driving have a much larger affect on MPG than most anything else does (Something like 60% of MPG comes from driving style. I can't remember the exact number).
2. Lighten the car. If you never drive with anyone else in the car, take out the passenger seat and back seats. Remove the spare and replace it with some fix-a-flat. If you want to spend some money, buy a light-weight battery and even light-weight wheels and tire (much more money I know).
3. Tune the car. Find someone with a tuner and play with your fuel maps. Be careful not to lean them out to much, but you can gain some MPG there.
4. Regular maintenance. Change your fluids regularly. ALL your fluids: oil, trans, rear end, etc. Check your tire pressure. This is a big one that most people over look. Check it every time you fill up. It takes hardly any time and can increase your MPG, life of your tires, ride quality, etc.
These basic things can easily net several MPGs difference if not more. They are much easier to do than DOD. I am within most everyone else, I don't think that DOD can be effectively pulled off with the LS1 without some serious re-design of the engine.
It seems to me that you could get much better gains in FE if you did some simple free mods:
1. Drive smart. Don't floor it. Keep the revs as low as possible (shift around 2500 RPM or lower). Drive around 60-65 in the interstate. etc. Studies have show that mood and style of driving have a much larger affect on MPG than most anything else does (Something like 60% of MPG comes from driving style. I can't remember the exact number).
2. Lighten the car. If you never drive with anyone else in the car, take out the passenger seat and back seats. Remove the spare and replace it with some fix-a-flat. If you want to spend some money, buy a light-weight battery and even light-weight wheels and tire (much more money I know).
3. Tune the car. Find someone with a tuner and play with your fuel maps. Be careful not to lean them out to much, but you can gain some MPG there.
4. Regular maintenance. Change your fluids regularly. ALL your fluids: oil, trans, rear end, etc. Check your tire pressure. This is a big one that most people over look. Check it every time you fill up. It takes hardly any time and can increase your MPG, life of your tires, ride quality, etc.
These basic things can easily net several MPGs difference if not more. They are much easier to do than DOD. I am within most everyone else, I don't think that DOD can be effectively pulled off with the LS1 without some serious re-design of the engine.