So Ive read the dozens of posts about engine swaps, but Im still unsure. I have a '99 4.8 4wd with a 5spd. I was wondering exactly what I would need to do to install a 5.3 or 6.0 and still keep it Cali smog legal. Thanks in advance for the advice.

 

Just do not go wild on a cam or add long tube hearders. Also you need the early 24x reluctor wheel.

The smog station only measure ppm or a fractional based assement. So if a 408-421 stroker LS puts out the same ppm or fractions of exhaust as a 4.8 the smog tester will never know.

 

Yep, the block is a direct swap, you'll just need the PCM tuned for a 6.0 versus the original 4.8.