Hello,


2011 Grand Sport, 70,000 miles

First, I got some squeaking once the weather got cold from the engine bay.

New belt and Katech tensioner installed a while back and had no issues with squeaking. Removed the tension and spun the pulleys. Water pump seems to spin very freely (see video). I'm assuming it's toast. Any feedback appreciated.


Also, while I was under there, I heard this click click or knock knock sound every few seconds. Somewhat rhythmic (see second video towards the end). Never heard it before, although with headers, big cam, and loud exhaust hard to hear things at times lol. Thoughts or ideas welcome as well.


No codes on the vehicle at all, pulls hard, is a blast to drive, turns heads everywhere I go. Maybe the infamous piston slap? This video was on cold start. I can check for the noise again after engine gets to temp.

Build is as follows on it (bought it this way):

-Texas Speed stage 3 boost cam

-Texas Speed springs and rods

-BTR Trunnion kit

-New lifter and trays

-160 Degree Thermostat

-Heads are ported by Performance Clinic Custom Engines

-Ls9 Headgaskets

-ARP Headstuds

-Stage 3 built transmission (built by TK performance)

-Circle D Torque Converter (3600 Stall)

-Upgraded Transmissions cooler

-Stand alone fuel pump good for (1200hp93)

-Flex Fuel Sensor(E85)

-Fuel Injector Clinic 1100CC injectors

-8 Rib accessory drive with a 8 rib 10% underdrive balancer

______

*Update-ish*

Let the engine get up to temp after driving and took another video. Doesn’t seem like the knock or click or whatever you’d describe it as is as noticiable. Hard to tell.