are there any bad effects of engine breaking? ive been doing it most of my cars life and ive been told it saves a lot of ware on clutch + other drivetrain parts...true? idk just wondering

 

Id like to know this too

 

It's no biggie if you don't do it too harshly and don;t care of the engine lasts 200K miles.

It burns more gas and it wears your cylinder walls in the opposite direction (opposite load direction than normal), but it's not that big of a deal. Yes, your rings will wear out a little quicker from it, but not usually enough to worry about.

If you do it harshly (dropping the clutch hard to let it pull you down and/or form a high engine RPM) you could tear a bearing cap off of a rod. It doesn;t happen often, but the risk is there. Rods are designed to handle maximum load pushing the rod into the crank journal, but they;re not nearly as strong when you try to pull the caps off of the rods with the journal. This is another place where good rod bolts might help.

Probably too much info, but hey, I answered the question!