lookin at doing something to my engine, and was lookin at gettin heads and cam installed, thing im wondering about though is when its real cold out or cars sat for a while it has a knock to it or until it warms up, guessing piston slap.
is putting heads and cam on it a bad idea at this point? i know its a common thing for these style engines but i don't wanna drop a couple grand in the engine to have it die on me in a few months later, wasnt sure if it was the same thing h/c as stock just let warm up before u drive or no, thanks

 

how many miles on the engine? where you spraying it?

 

106500 miles as of right now, and no never sprayed and don't plan too, it runs great, dosnt smoke or anything and if the first start of the day is above about 75 degrees air temp it dosnt make any noise

 

What oil do You run ?

 

My 2000 Z28 with 109,000 has a little knock or slap on cold days or after sitting. It goes away after about 15 seconds of driving. I'm wondering if the sound could be typical for these motors after 100,000 miles. I use a synthetic oil, and change every 6 or 7 thousand miles.

 

I think you are heaing piston slap when its cold

Do a compression check-if you get good numbers than go for it!

 

yeah im guessing piston slap, and i run royal purple in it, changd every 4-4.5k miles, and ight cool

 

You would do the same with the H/C combo as the springs are much more brittle than stock and cannot take WOT until they are up to temperature.

 

Search for threads on motor oils...I think in the advanved tech section.....
There was one very informative one that talked about different composition
aspects and elements of dino vs. synthetic. Some claimed that their engines
were more noisy when runnin' Royal purple. Not saying this will solve your
dilemma as G.M. even went to teflon coated piston skirts around 2000-01
for quieter cold startup. Many people swear by Mobil 1, AMSoil, or Lucas
for the least amount of racket. I've even had good luck runnin 0 weight
Mobil 1 in my Silverado SS since the main reason for piston slap is the low
tension piston rings inability to pull or drag thick(cold) oil up the bores on
initial startup. My lq9 would stop rattlin imediately and had great oil pressure
when I sold it @ 72000 miles.....13.1 @106 with a .062 dry-shot...I'm stupid