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Discussion Starter #1
I have a stage 1 9-5 aero and at high rpms im talking about 5500-6300 my engine makes this kind of rattling tin can kind of noise and power backs off a bit. It does not happen all the time, mostly in 2nd.
 

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Sounds like you are pre-detonating. It's likely that you will need more fuel and/or timing adjustments. At any rate, avoid it at all costs until you can get the cars tuning sorted out.
 

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Timing chain!!!!!

That, my friend, is the audible sound made by a timing chain that has stretched too far. Have your mechanic measure the amount of stretch and replace the chain if it has stretcheed too much. The stretched chain is striking the valve cover causing the sound. This excess bowing of the chain is also causing a mild change in timing of the intake vs exhaust valves as the angular position of the cams must change slightly due to the new arc in the timing chain path induced by the high RPMs. This is what is causing the loss of power.

Cost to have a new chain rolled in (not possible in all situations) will probably be ~$500. If the chain guides are too deeply worn a roll-in is not possible. In this situation the engine will need to be removed to access the front cover to replace all chain guides too.

Cost if you don't have this checked and replaced might be a new engine. A stretched chain can jump a tooth or two on the cam shafts.
 

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Discussion Starter #5
I don't think it's the chain, because if it was wouldn't it be happening every time I hit the upper rpm band
 

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i adjusted my wastegate and gap and it isnt making that sound anymore but now its doing something different. At the upper rpms it backs off the power kind of like if it went from 15 psi down to 5psi althought the boost is still the same.
 

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i adjusted my wastegate and gap and it isnt making that sound anymore but now its doing something different. At the upper rpms it backs off the power kind of like if it went from 15 psi down to 5psi althought the boost is still the same.
If it's pulling timing or adding excessive fuel, it would result in a drastic reduction in power.
 
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