help: rattle past 4k rpm from redtop sr20det

[rexify]

I was reving up my engine past 4k yesterday and it made this weird medium to high pitched rattle from the engine. I decided to drive it and it still made the same noise after 4k rpm. I makes that same noise as a loose rattling heat sheild but I dont have any heat shields anywhere. Does anybody know what this rattle could be?

I have a redtop sr20det and it had never made this noise before. Only put 1,000 miles on it after the swap.

[JRPS13]

if it sounds like clapping, id have to say maybe detonation... check your timing....

[jaco]

check the locking tab that bends over the nuts (nohomo) that bolts the turbo to the manni..one of my nuts vibrated/backed all the way off and the tab was just buzzin on there ...strangly enough i heard it the worst at exactly 4k too.

[SpeedRacer1]

Possible blown or loose manifold to turbo gasket.

[rexify]

found out what it was. I one of my exhaust bolts wiggled its way out!. I got a new bolt and tighten it like crazy!no more rattles!Thanks for the help!