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Discussion Starter · #1 ·
I figured out a way to save gas on the supra. You'll need:

4 switchs
20 ft electrical wiring

Basically you want to wire in a switch between the fuel injectors and coils 1,6 in series. After you have done this take it for a drive on the freeway; you can now turn off cylinders 1,6 on the fly when you are just cruising and don't need the power.

Other things you can do:

light driveshaft
light rear wheels
don't fill up the tank more than 1/2
water injection (didn't see much of an improvement)
free flowing exhaust
use hotter spark plugs with slightly wider gap(careful though, detonation may occur)
fuel computer

Hope this helps. :)
 

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The Radiator Man
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sweet!
how much did it affect it?
 

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wouldn't this cause engine damage??
 

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neat idea, i don't think it would hurt the motor.
So your cutting the injector signal?
Does the cylinder still have spark?
 

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spoolint78 said:
neat idea, i don't think it would hurt the motor.
So your cutting the injector signal?
Does the cylinder still have spark?
Nope, you run both to a switch.


But, wouldn't it be better and create a more even load if you cut the spark and injections to 3 total? I thought our (actually your, I'm N/A) cylinders fired in pairs.
 

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Fish tacos
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marc1131 said:
Doesnt chevy do this on most of their v-8s to save gas?
Yes, The 80 DeVils were FF and 8 clyyanders but can shut down two or four. The only problem is they didnt really turn them back on.
 

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Yeah alot of car companies do this now. I'm pretty sure Caddy has been for a while. The whole power on demand idea.

When you go WOT you get all the cylinders pumping other than that just thew few you need to move.

However given the fact that 1 and 6 would not be firing and they are the like balanced set would that cause some out of whackness with the engine in its entirety? I mean if you go from 6 cylinders turning the crank to 4 with power and 2 that would still be dragging away power wouldn't that cause some balance issues or stress on the crank?
 

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What would be optimum? 1, 3 and 5 off and 2,4, and 6 firing? Possibly the reverse to let the back of the block cool.
 

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Not ur jizz, not ur bizz
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Lord Mike said:
Yeah alot of car companies do this now. I'm pretty sure Caddy has been for a while. The whole power on demand idea.

When you go WOT you get all the cylinders pumping other than that just thew few you need to move.

However given the fact that 1 and 6 would not be firing and they are the like balanced set would that cause some out of whackness with the engine in its entirety? I mean if you go from 6 cylinders turning the crank to 4 with power and 2 that would still be dragging away power wouldn't that cause some balance issues or stress on the crank?

The Dodge Charger does it...shuts down 4 cylinders i believe...or was it 2? meh i dunno, heard it does real well on highway mpg.
 

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Discussion Starter · #15 · (Edited)
I only wired 1,6 to stop firing because I figured it would better balance out the engine.

I got the idea when I was trying to figure out if my 7m had rod knock or not. lol. Turned out to be a stuck valve.

As far as gas savings go, I'm not sure about that yet; I've only wired it last week. lol. So far though it seems to help though, I got ~32 miles to the gallon on the highway the last time I checked; drove at around 3k rpms ~75 mph with 3 gallons in the tank. Usually when I drive at that speed I would get ~27 mpg.

Seems to help a bit, but I'll need to do some more driving and make sure I am really improving my gas mileage. haha.
 

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Discussion Starter · #17 ·
InvisibleMonkey said:
that's actually a really good idea, i'd just be worried about any damage that may happen
I'm worried about that too... but I figure the cylinders probably have a higher chance of getting damaged when it's actually firing.
 

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How about a system which rotates the sleeping cylenders along with a small override switch (magnet and reed perhaps) attached to the throttle cable as an override? I'd be inclined to add an RPM sensor set to about 3500 or 4000 to override it as well.

I think the main concern isn't going to be low RPM cruising though... torque during acceleration, I think, could cause some problems.
 

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CRE said:
I think the main concern isn't going to be low RPM cruising though... torque during acceleration, I think, could cause some problems.
all you have to do is turn #'s 1 and 6 back on when you want to accelerate...maybe put a switch on the steering wheel or the shifter to make it easily accessible when doing so

EDIT: also, wouldn't you slow down when turning off #'s 1 and 6? and have to increase throttle to maintain speed
 
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