i heard from a few people at work , that underdrive pulleys can harm your timing chain and or valve train overtime ,due to the oil pump turning slower.ive had one on my truck before , for about a year and no problem. but no my engine has 280k on it and just wonderin. thoughts?

 

Should be turning the same amount since those aren't ran off the belt.

 

oil pump is crank driven so it spins the same no matter what pulley is bolted to it
Hear say will often steer you in the wrong direction

 

x2 !!! Well said.

Seems everyone knows what is best for ''YOU'' haha !!!

 

As said above, only your belt driven accessories are slowed down with a small crank pulley

 

Unless you have a dry sump setup it wont affect your oil pump. lol

 

i knew the oil pump was gear driven. guess i wasnt thinking, lol., what about the wear and tear from the lack of a dampner?

 

have you ever looked at your crank pulley? lol

 

Z06 MS4 cam balancer incident - YouTube

Don't be like these idiots and not install a new harmonic balancer bolt . Also, if you have upgraded to efans you might think about getting an overdrive pulley for the alternator.

 

how many ft pounds should the torque of the crank bolt be?