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Old 01-10-2012, 02:35 AM   #1
TravisL
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Default Engine knock/rattle UNDER 2000 rpm

I just put an ej253 into my 02' outback. I did not connect the i-avls, I just left it alone entirely.

I plugged the egr hole on the drivers side head, and plugged the one tube that my intake didnt have a place for, leaving only one tube to be connected for it I believe.

All new timing belt, tensioner, idlers, water pump etc went on. After putting the timing belt on, with the plugs out I rolled the motor over by hand for a while and everything felt good, and sounded silent.

The car runs well, but sounds like holy hell under 2000 rpm. I can rev it to 2000rpm and the sound vanishes like a light switch. The motor is from a 2008 and I'm told it only have about 30k miles on ti. Power wise, it's alot better than what I had, and I think just right for an iavls car that isnt hooked up......

I've not seen a noise that just goes away with rpm's increasing that seems counter intuitive as hell me me. I dont know if it's pre-ignition, loudest exhaust leak every....but it's a hell of a knocking sound. Completely goes away a 2000rpm warm or cold doesn't seem to matter.
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Old 01-10-2012, 03:28 PM   #2
GEE-OTTO
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You might want to find a way to get that AVLS functional
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Old 01-10-2012, 06:39 PM   #3
TravisL
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Technically speaking it is working at idle lol.

Despite what has to be a very mild profile on on intake lobe, it runs better that the ej22/ej25 combo I pulled out.

Found the noise, lucky I didn't bend the valves, timing belt is loose. Still haven't had time to find out why, but that's def my issue.
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Old 01-10-2012, 10:28 PM   #4
RaceFaceXC
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You can apply 12v to the AVLS solenoids to energize them and allow oil pressure to lock the rocker assembly in the high lift position, but idle will be rough. if you can figure out a way to switch it automatically, that would be ideal. There has been some discussion about this exact issue in the recent past on here. A search should turn up some results. I can't remember what the thread topic was where the AVLS discussion took place, but i think there was a link to it in at least one other thread so it shouldn't be impossible to find. search by post, if a by title search doesnt turn up any good results.
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Old 01-11-2012, 01:03 AM   #5
T Wrex--OH
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Wouldn't an RPM activated window switch do the trick of activating AVLS at a desired RPM point?
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Old 01-11-2012, 01:44 AM   #6
TravisL
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Near as I can tell it will T Wrex. I'm looking into doing this, but I'm not sure I want to apply a true 12v constant signal, from the factory they are fed by the ecu an 80% duty cycle....maybe I'm splitting hairs. Besides working for a while would be better than no working at all right?
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Old 01-11-2012, 04:13 PM   #7
T Wrex--OH
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I think it would work just fine. Better than making the sacrifice of having a rough idle if it isn't necessary.
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Old 01-11-2012, 06:24 PM   #8
TravisL
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I'm sure its not huge, but I do wonder what power and or effeciency(mpg) gains are made over the system being non functional, the 06 is rated at 174 vs 165 in addition I'd thin I'd beunder the 165 due to that one really mild cam profile. I might be crazy, but this might gain me 15hp at the crank?
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Old 01-12-2012, 12:11 PM   #9
RaceFaceXC
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Another part of the 15hp gain is the exhaust manifold design on the 06+. I think the combustion chamber design is different, also. The higher profile cam lobe probably does more for midrange and high rpm effiency that for peak power numbers. If you could see the tq curve side by side, I bet the area under the curve would be much improved with the higher lift lobe.
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Old 01-15-2012, 03:12 PM   #10
TravisL
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Yeah, its not as if I'll be dyno'ing it or anything. It'll be a slow outback reguardless, but if I can see a real gain in power/torque for a $50 rpm swithc why not give it a shot.
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Old 08-02-2012, 12:07 PM   #11
02darkRS
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For search purposes, here is the AVLS thread: http://forums.nasioc.com/forums/show...ht=avls&page=3

I believe I also replied to your thread on the outback forums, for search purposes. Can't believe you had a loose belt without internal damage. You got real lucky there.

I've been running on the low lobe for 4 yrs or so without issues. I am really looking forward to applying a manual signal to the high lobe. Did you ever do it travis? My follow through on this will be posted on the linked thread. I'm waiting for teslamaster to have some time to walk me through the wiring.
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Old 08-02-2012, 03:31 PM   #12
Grindbeard
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Quote:
Originally Posted by T Wrex--OH
Wouldn't an RPM activated window switch do the trick of activating AVLS at a desired RPM point?
A lot of the Nissan Sentra guys do this when swapping in an sr20ve. Maybe check out sr20.net?
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