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VANOS timing, for nerds.

Discussion in 'E46 (1999-2006)' started by majewski, Apr 13, 2009.

    majewski guest

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    I have an M54 in my e30 but this wouldn't go very far in the e30 section....

    I have some standalone electronics that control the VANOS timing for me and I can advance the intake and retard exhaust at my will. No, not MOTEC or such but something I developed myself.

    I went to the dyno the other day to see where different amounts of exhaust retard made power and found that any amount of exhaust retard actually hurt my power across the board at WOT. 4 degrees, 8 degrees, 12 degrees. They all killed power at any rpm.

    What I am gathering from this is the possibility that my cams were not timed correctly when I re-installed them. I did it by the book with the cam locks and depth plate, etc, but theoretically I should see some gain at higher rpms by retarding the exhaust cam.

    My question is, how can I find the spec for what the cam timing should be in terms of crankshaft degrees? My circuit allows me to measure my actual cam timing with respect to the missing tooth on the crank toothed wheel. My Exhaust cam signal changes at 113 degrees past the missing tooth and the intake signal changes at 252 degrees. This is when the cam wheels change state at the Hall sensor.

    If anyone in the Seattle area would allow me to measure their M54 signal that would be one way.

    If anyone has access to the tech specs on this that would be very helpful!
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    I saw this on r3v. Nice work, btw. I'll see what I can dig up for info at the shop, but it may not be much. I can scope one with the Autologic if you think that will help. It should tell me what the cam timing is at any given time. You'd have to wait until I got one in the shop, though. I'll also hit my brother up for info, since he builds these motors. If he can help, I'll get you his info, because this might be useful to his shop.

    majewski guest

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    Thanks, there is also the possibility that I did time the cams correctly. I'm not entirely sure that BMW would specify cam timing for maximum power, I suspect they would set it for best emissions and maybe power if it didn't hurt emissions.

    I expected to see a slight increase in power at higher rpm's with a small amount of exhaust cam retard but found that in reality I lost power across the board. That means that either (1) I have them timed incorrectly or (2) exhaust cam retard isn't meant to increase power but to increase efficiency or emissions through internal EGR when timed to factory specs.

    I don't have it connected through the stock computer to trigger the CEL, but I also don't need to worry about the CEL if I advance it beyond the factory setting.

    I agree that this could be useful information, I measure the the signal from the cam wheel in reference to crank degrees from the missing tooth. If you scope it, one channel would be crank signal and the other would be intake or exhaust Hall signal.

    The good news is that the dyno showed a STRONG response to intake advance. I could also use some more static advance on the intake cam.

    If I decide to advance the exhaust and/or intake cam, could I just loosen nuts "B" in the attached photo and physically advance the cam while holding everything else steady?

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