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Is the MILVS Mod Only Effective at 80%+ Gas Pedal Position?
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01-19-2019, 02:56 PM | #1 |
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Is the MILVS Mod Only Effective at 80%+ Gas Pedal Position?
After reading on the forum, my understanding is that the MILVS mod only provides increased valve lift at 80% and greater gas pedal position. Is this true? Even after you get the BPC MILVS tune?
Last edited by Wurx; 01-21-2019 at 06:54 PM.. Reason: provide clarification |
01-19-2019, 04:45 PM | #2 | |
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The DME uses the valve lift to control engine load while the throttle is more of a back up device. |
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01-19-2019, 06:05 PM | #3 |
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I feel the difference regardless how much throttle I give. So, from my personal experience, your statement is false.
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01-21-2019, 09:41 AM | #4 |
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The tune doesn't really have any affect on how the MILVS physically operate. You just won't make a lot more power without re calibrating for the extra lift - the engine thinks maximum lift is 9.7mm but it's really closer to 11mm.
As far as "no effect until 80%" that's not really accurate and a misinterpretation of what Marty originally posted. The goal of MILVS was to change the rocker ratio curve to gain lift at full throttle but not affect low throttle or closed throttle positions (because that would negatively affect idle, emissions and driveability). They are machined so the change at low lift positions is minimal (basically 0 at closed throttle), and increases as you get closer to full lift. So there is a much bigger difference in lift at 90% eccentric shaft position than there is at 20%. It's not an "on/off at 80%" thing at all. |
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01-21-2019, 06:57 PM | #5 | |
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01-25-2019, 03:12 PM | #7 |
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I see the effect of the MILV mod as pre-loading the valve spring. Can anyone explain how the supports are machined such that the valve springs are only affected during high cam angles? Genuinely looking to learn more about this. My last post on this was backwards as I was assuming that the actual seat was being machined down and not the point where the support bolts down.
Lift should only be occurring when the cam gets into the elliptical portion of the lobe to cause lift. If the preload of MILVS was so great as to cause lift during the other 80% of the cams rotation then you would have little to no compression. Last edited by bbnks2; 01-25-2019 at 03:28 PM.. |
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01-25-2019, 06:15 PM | #8 |
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01-25-2019, 09:12 PM | #9 | |
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