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  1. roflwaffle

    Shade tree cylinder deactivation?

    That's good to know Tmoose, and makes a lot of sense compared to results I've seen people report. Pat, I'm not adverse to your statement that it won't work, however Brian has been explicit about throttling losses, for instance how just blocking the intake wouldn't work, and according to the BSFC...
  2. roflwaffle

    Shade tree cylinder deactivation?

    I see what you're referring to Brain, but then the problem isn't catalyst light off, since most of the heat via the exhaust stream will be the there, the problem is that in a lean mixture HC/CO reactions would be heavily favored, in other words NOx emissions would increase running on just three...
  3. roflwaffle

    Shade tree cylinder deactivation?

    So long as I cut-out the heated oxygen sensor that checks on how well the cat is working, and the sensor associated w/ the bank I cut, emissions shouldn't be too bad. The oxygen sensor in the active manifold would still be working fine and I'd be at ~14.7:1. In terms of EGTs, why would running...
  4. roflwaffle

    Shade tree cylinder deactivation?

    I see what you're saying about having a restriction on the intake. What about scratching the shut-off of the intake runner since that was only because I was worried about the piston/rings getting too cool and wear increasing, which supposedly isn't a big issue? Wouldn't the inactive bank just...
  5. roflwaffle

    Shade tree cylinder deactivation?

    I'm curious. When you say that in order to reduce pumping losses the valves need to be deactivated, is that assuming a near optimal gear ratio? To put it another way, lets say that cruising down the highway at 55mph w/ a 3L engine and I'm turning something obscenely high, say 4,000rpm, and BSFC...
  6. roflwaffle

    Shade tree cylinder deactivation?

    I don't expect the increase in fuel efficiency to be proportional to the decrease in power at the time. I figure I can just rig up a couple switches to kill one bank and it's Oxygen sensor so the bank left on won't run rich and pick up a few mpgs. I've plotted the required output at some speeds...
  7. roflwaffle

    Shade tree cylinder deactivation?

    Good point! Maybe I could set up a timer to alternate between which banks were deactivated after I figure out how long it would take for the cylinder to get oiled up to the point where it would cause trouble.
  8. roflwaffle

    Shade tree cylinder deactivation?

    Good to know!
  9. roflwaffle

    Shade tree cylinder deactivation?

    I should also add that if cooling the pistons/rings on the deactivated bank wouldn't increase wear, I wouldn't bother in the first place. So I suppose a better question is how much does cooling the piston/rings increase wear? For instance, would having an electric motor turn a cold engine result...
  10. roflwaffle

    Shade tree cylinder deactivation?

    I was planning on closing off the intake runners on the deactivated bank in order to minimize cooling of the pistons/rings and hopefully any potential for increased wear/blow by on the deactivated bank. I don't mind much pumping losses associated w/ moving air in and out of the cylinder, which...
  11. roflwaffle

    Shade tree cylinder deactivation?

    I've seen this idea tossed around the web, supposedly w/ some success w/ V engines. I'd love to see it done w/ my V6 sedan, since it would allow me to cruise at a relatively slow speed where possible (~45-55mph) w/o being in an undesirable portion of my engine's BSFC map. The downside to doing...

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