does a Turbo Charge decrease the life of an engine? - Page 3

Quote:

Originally Posted by rhythmdevils 

Can you say more?  That seems to go against what a lot of people are saying. 

 

My friend made a good point.  He had an Eagle Talon and said that at freeway speeds of 70mph, it ran at around 4000rpm.  Many non turbo engines would be running at 2000rpm at the same speed.  So if you look at engine life in terms of number of fires, that's half the lifespan.  But I'm not sure all turbo'd engines run that fast.

Turbochargers, Supercharges, and Nitrous all create higher cylinder pressures. This DOES reduce engine life ... PERIOD.

Turbos and Superchargers make more heat, and heat reduces an engine's life ... PERIOD.

Quote:

Originally Posted by downsize 

 

Turbochargers, Supercharges, and Nitrous all create higher cylinder pressures. This DOES reduce engine life ... PERIOD.

 

Turbos and Superchargers make more heat, and heat reduces an engine's life ... PERIOD.

Heat can be largely dealt with if you have a proper intercooler. Sure, an engine may last some unspecified amount of time less with forced induction, but the question is whether that amount of time is appreciable and whether it matters to the driver. If an engine that can go to 400k miles only lasts to 300k because of a turbo, that's no big deal- almost nobody drives a car that long. The bottom line is that most factory forced induction cars have motors that almost always last longer than most people care to own the car. 

Yes, if you want to run 40psi through your stock civic motor, it won't last too long- but that's not what we are talking about here. 
 

Quote:

Originally Posted by nealric 

 

Heat can be largely dealt with if you have a proper intercooler. Sure, an engine may last some unspecified amount of time less with forced induction, but the question is whether that amount of time is appreciable and whether it matters to the driver. If an engine that can go to 400k miles only lasts to 300k because of a turbo, that's no big deal- almost nobody drives a car that long. The bottom line is that most factory forced induction cars have motors that almost always last longer than most people care to own the car. 

 

Yes, if you want to run 40psi through your stock civic motor, it won't last too long- but that's not what we are talking about here. 
 

Indeed. Pressure built by turbo on efficiency aimed engine is very small, the stress it adds to the engine is rather minimal. Situations where we are compressing tons of air to cylinders aiming for insane peak powers is rather different than just merely putting otherwise wasted exhaust energy to good use.

Quote:

Originally Posted by rhythmdevils 

 

My friend made a good point.  He had an Eagle Talon and said that at freeway speeds of 70mph, it ran at around 4000rpm.  Many non turbo engines would be running at 2000rpm at the same speed.  So if you look at engine life in terms of number of fires, that's half the lifespan.  But I'm not sure all turbo'd engines run that fast.

Gearing issue, not a turbo issue.
 

Quote:

Originally Posted by nealric 

Heat can be largely dealt with if you have a proper intercooler. Sure, an engine may last some unspecified amount of time less with forced induction, but the question is whether that amount of time is appreciable and whether it matters to the driver.
 

An intercooler reduces the temperature of intake air to increase intake air charge density. Higher air density means that you can dump more fuel into the cylinder to create more power. It doesn't do anything to reduce engine or underhood temperatures, both of which are much higher on a turbocharged engine than its naturally aspirated counterpart.

Even though factory engines are designed to take the additional stress, there's still an increase in the number of catastrophic failure modes. More heat under the hood means more things to can go wrong faster, plus the various turbo specific failure modes. Yay for broken oil return tubes and cracked ringlands.

Quote:

Originally Posted by MaZa 

Indeed. Pressure built by turbo on efficiency aimed engine is very small, the stress it adds to the engine is rather minimal. Situations where we are compressing tons of air to cylinders aiming for insane peak powers is rather different than just merely putting otherwise wasted exhaust energy to good use.

It's a bit more than an efficiency boost on Subaru's turbocharged 2.5l flat 4's. It's anywhere from a 33-85% increase in output depending on the turbocharger and tune used. As with most hot hatch engines, the use of a turbocharger is a packaging compromise. There isn't enough room to fit a larger and more powerful engine in the engine bay of an economy car, so a turbocharger is used to make up the difference.

Cost is higher, reliability is lower, powerband is crappier, but dang it, it allows you to fit a reasonably potent mill into a car designed for the $15-18k price point and charge an arm and a leg for it.

Quote:

Originally Posted by marvin 

It's a bit more than an efficiency boost on Subaru's turbocharged 2.5l flat 4's. It's anywhere from a 33-85% increase in output depending on the turbocharger and tune used. As with most hot hatch engines, the use of a turbocharger is a packaging compromise. There isn't enough room to fit a larger and more powerful engine in the engine bay of an economy car, so a turbocharger is used to make up the difference.

 

Cost is higher, reliability is lower, powerband is crappier, but dang it, it allows you to fit a reasonably potent mill into a car designed for the $15-18k price point and charge an arm and a leg for it.

Indeed. But its car dependant and what they are their aims with the turbo. With Subaru its obvious they want a lot of punch out of their small displacement engines, if we are talking about Imprezas and whatever pseudo-sportscar. Their engines are pretty much built to last that stress anyway, but abusing it I can very well seeing the lifespan being noticeably shorter. Turbo-diesels on the other hand can last a lifetime, mechanically anyway. Electric problems are always a bitch on nowaday cars (talking about my friends KIA diesel SUV that started screwing up couple of weeks after buying).

Guys .... there is a WHOLE LOT of things that can be done to help a forced induction engine last longer .... Build it correctly, size the power adder correctly to the application, big intercooler, water injection, etc, etc ....

But my answer to the OP is still correct .... ANY power adder WILL decrease engine life to some degree.

But then what would I know ???   I only recently sold my little 4 cylinder that ran 9 second 1/4s at 138mph.

Engines in any well made daily driver today do not fail due to chronic heat/pressure stress.  Sure, every material is subject to physical stress, heat, pressure...and engines are no exception.  But those factors are not dominant design considerations when one has modern alloys to work with, and when other constraints dominate the design of the car.  Shoot...when the car eventually dies, I would wager it won't be due to anything at all in the engine.  To assert that a modern turbo implementation will have a negative impact on the lifetime utility of the car is misleading.

I don't think anyone objects to the observation that increased heat and pressure puts more strain on an engine.  However, I, for one, object to the assertion that the differential increase in heat/pressure leads to a noticeable increase in engine failure, and to the tone you employed to state a glaringly obvious fact of internal combustion engines, PERIOD. 

Quote:

Originally Posted by downsize 

 

Turbochargers, Supercharges, and Nitrous all create higher cylinder pressures. This DOES reduce engine life ... PERIOD.

 

Turbos and Superchargers make more heat, and heat reduces an engine's life ... PERIOD.

You will never find an agreement.

Get the turbo. You get more power for a nominal loss of highway efficiency.

A MFR cant afford to make a "bad" car with today's press, and generally longer expectations of how long a car should last. Simply put they don't you should expect (and most likely will find that) the turbo car last equally long as the inferiorly aspirated engine (oops, I meant naturally aspirated). 

With modern turbos with water cooled bearings it is not uncommon for the turbo to last as long as the engine and certainly much longer than they did in the 1980's when everyone made the last push for turbo cars. Dont forget that during the big push for turbos in the 1980's people were impressed that any car went much more than 100Kmiles without rebuilding the engine, transmission or both! If any car company made a car that regularly turned up dead before 100Kmiles there would be public outcry followed by a class action lawsuit, followed by a warranty extension or outright recall. In either case the costs for putting an iffy car on the road are far too great and no MFR can afford it, even if it is only the performance version.

Problems that forced induction engines used to have due to iffy engine management simply dont exist any more. That is sooo outdated that its laughable. Modern computers have much better control of fuel, ignition, MANY MANY safety systems, and engines are simply built better.