Would like your opinions. Worry about piston slap, or not?

**Rob00Taws6** · 06-11-2007, 05:56 PM

Personal I have owned a few third gen. Camaros and trans ams. I built a Lingenfelter L98 for my 89 GTA. My first Ls1 was in a 2000 corvette, I traded that car in for a 2000 trans am. I’ve always envied the Ls1, and I still an amazed by the engine. But, the two Ls1 that I have owned have had piston slap issues. I feel that there are mixed opinions about in regard to this issue, all I know that as many people that tell me that its normal, it sure in embarrassing after a cold start at the curse night. I know that the noise diminishes after the engine comes to operating temperature. My corvette didn’t quiet much. With my trans am the slap is loud at first then quiets, there is still an audible ticking but I feel that it is something else such as a noisy EGR valve or the exhaust. I have come to the conclusion that I wont be able to do any thing about it till I rebuild or replace the engine. I also feel that this piston slap issue is harmless, and will not effect the longevity or performance of the engine by the nature of the problem (piston to bore clearance, and combination or short piston skirts). I understand that in may cases its apart of reducing friction in a high performance engine. But, I would like your opinions.

**99bluebird** · 06-11-2007, 06:19 PM

Definetly look into the PCV and exhaust leak possibilities because its cheap. If you narrow it down to internal components than I wouldn't worry about rebuilding it until you plan to install some serious forged components. Otherwise its all just a matter of how much it bothers you vs how much money you can spend.

**danziger** · 06-11-2007, 11:32 PM

Piston-slap is WAY over-hyped. The design of the piston, rod length and ring package cause some cold-start noise in some engines. No big deal. I had more "slap" in my 5.0 GTs with their forged slugs and look at how durable that engine ahs proven to be...
I wouldn't lose any sleep over it.

**LETHALxLS1** · 06-12-2007, 08:55 AM

It sure does make you cringe to hear it when you first start your car-thats for sure. I know people say that oil shouldnt play a part in quieting the slap but in my car it does. I tried Royal Purple and the slap sounded louder and lasted longer. I put regular Valvoline 10-40 back in her and its much quiter until it gets warm. Just my 2 cents.