Ricky_GD

Hi i have a Gardner Douglas kit car Cobra with an LS1 engine in, took it for its first track day last weekend ! now there's one knocking noise that has been annoying me for a while now, only happens when its cold ( so I'm hoping its piston slap?) sometimes it doesn't happen at all!?? but the noise gets louder as soon as you start to drive, when its warm it is fine. oil pressures a good 60 psi cold and 45 warm, i have done a search but cant really say its defentley piston slap , are there any other possibilities with these symptoms?

thanks

98RedBird

iTrader: (77)

Probably piston slap. No I don't know for sure, but it sounds pretty common to me. For example if it was a rod knock or something serious like that it would continue on just as strong when it warms up, it would never go away and become very noticeable under load. All you can really do is try changing oils around and see if it cures or lessens the problem.

Ricky_GD

cool cheers for the reply, i have 0-40 in at the moment think i might try 5-30 see if that helps, just need to find somone in the UK that sells decent oil filters!