Originally Posted by
freeman
Could someone tell me what the noise is coming from my GRP tuned. At idle it does not do it but at mid to full throttle then back down to idle there is a ratteling like sound. Almost like the rod is touching the block going up then back down. Checked everything and no rubbing of the rod. BTW the engine runs perfect stays tuned in everyway.
If you are running the FLS type pipe system check the o-rings that seal the header to the pipe. I had them leak and make my .21 tuned sound very loud. It took a very cold day to see the exhaust escaping out the FLS fitting.