I have the "infamous puff" of blue smoke when I start my 5.7 after it sits a couple hours; drives me crazy! No other problems with it. Anyone recently replaced valve guide seals in a 5.7, and if so, approximately what did it cost to do it?
A friend of mine said you can buy "smokeless" oil and that he has used it in some of his older Corvettes. It is quite expensive (17.00 a Qt.), but I was wondering if anyone else out there might be able to give testimonial to it. Thanks.

 

Any oil advertised as "smokeless" is going to be nothing better than snake oil.

Replacing the valve seals is a pretty straight forward job. It can be done with the heads on the engine, but you will need a large air compressor, spark plug adapter, and a puller for use with the heads attached. Start with the #1 cylinder at TDC on the compression stroke. Remove the spark plug and pressurize the cylinder with compressed air. Remove the valve springs on the #1 cylinder, replace the seals, reassemble the springs, and move on to the next cylinder following the proper firing order.