Another topic in a series of eternal disputes. I think most of the readers are personally familiar with each type of timing, depending on what kind of car it was, what kind of engine, there could be a certain opinion about reliability.
Until the 2000s, everything was quite simple:
Now everything has “a little” changed, let’s start with the chain, have you seen how it looks now? Indeed, the dimensions are not much different from the bicycle, what is the point, where does such savings come from? The design of the motor with a timing chain is that the chain is located in the oil bath of the motor, that is, the block and head are cast with space for the chain, the wider the chain, the more material is needed for the block, head.
In an era when they began to fight for the environment and increase efficiency, they got to the two-row chain. Reducing it by half, it turned out to save a few kilograms of alloys, as well as gain a few centimeters, which is also important, the extra few centimeters can be “moved” to the cabin, and the trend has gone to the transverse engine.
What did ordinary users get?
Replacing the chain is not the cheapest procedure, for example, six months ago, I changed the chain on a 2-liter VW Tiguan with a mileage of 90 thousand, the tensioner has already decently left, 28 thousand for work with spare parts, and this is an action of the VAG club service.
But why then do manufacturers still use chains in their engines?
On motors with a timing belt, at one time they began to actively use pistons with valve grooves, so that in the event of a belt break, the valves would not bend = even more expensive repairs than replacing the chain. Subsequently, many manufacturers abandoned such pistons in favor of more reliable timing belts.
It’s impossible to say which is better, the belt has its pros and cons, the chain has its own. Manufacturers use both approaches, for example, the same VAG