I posted this in the civic/crx forum but I figured the gurus here might be able to recognize this sound.

I know I'm due for a valve adjustment I just wanted to post this because it doesn't sound like the normal valve ticking you might hear.

It doesn't do it at idle just from about 2800 rpm up and its off and on throughout the rpm range. The noise happens whether the clutch is in or out. The car runs strong and tested the compression to 190-195 across the board

It just started a couple weeks ago and has gotten louder. Its not my daily so I don't drive it but on the weekends mostly

http://www.youtube.com/watch?v=9F033Lwuqrs

setup is a stock block turbo b16a tuned on Neptune RTP 305hp @ 10psi

 

sounds like a rod knock...bad bearing..drop the oil pan and check

 

X2, ill bet it is a bad rod bearing.

Do you have an oil pressure guage?

Best bet is to drop the pan and see if theres play in all the rods. Plus, check for metal shavings. Im sure youll find some.

 

Hmm! Yeah i have that same sound right around 5k rpm. I have already checked bearings and what not and there fine, i haven't had a single issue with mine. I purchased ls rods and pistons with ls crank and after assembly and driving the car i found out i have gsr rods in the car. so my pistons slap the head ever so slightly when its a cold motor so i accounted that noise to that problem. ive also removed the oil squirters in my gsr block thinking maybe they were hitting the crankshaft but that didnt help.

Car is being taken off the road and engine completely dissasembled in the next month to see whats going on and install LS rods so i dont have my current issues. Car runs great though.

 

Check your clutch springs and/or bolts. It's not uncommon for a bolt to come loose, or for a sprung hub to wear out its tabs. The springs can then rattle around or wear on the crank bolts. I welded new tabs to hold springs on a stock clutch once, lasted another few thousand miles before it got oil on it somehow.

Another thing may be the LMA's. I don't have experience with bad LMA's, but sometimes the old-style hydraulic parts will let the vtec lifters flop around.

If it was a rod bearing issue, you'd get higher or lower compression, since the piston will have a larger compression height as the others while it flops around.

 

With worn LMA's will I notice anything loose by touch when I pull off the valve cover? Are there any easily identifiable things to inspect?

I'll be having a look tommorrow night.

 

its really simple to pop the cams out and slide the rock rods out and take out the lma's for inspection.

 

sounds like a clutch issue.