Small Turbo's

[Bper]

This subject has intrigued me since buying my Auris 1.2T and the comments about small turbo engines. Should there be any real concerns today regarding the longevity of these engines providing the car is driven sensible and why should these engines develop any more issues then other turbos

Turbocharging has become a common way for auto manufacturers to strike a balance between power and fuel economy. The concept is to allow a small engine to work like a bigger one when more power is needed. This is accomplished by forcing more air into the engine during acceleration, enabling it to burn more fuel. But with the increased stress caused by turbocharging, will these cars end up off the roads earlier than their naturally aspirated counterparts? Or will they go the distance due to improved research.

Why would toyota risk it's reputation for reliable under question by developing a engine that may not have longevity.?

 

 

 

reliable  

[Cyker]

Generally a turbo or super-charged engine won't last as long as an NA as they are more stressed, as you say, but where everyone else is going for power and putting in too much boost, Toyota engineered the 8NR-FTS to be reliable and only lightly boosted it, so while it doesn't get the headline horsepower figures of a lot of its rivals (Which are misleading anyway), it has a lot more useable mid-range torque and doesn't stress the block as much.

Aside from the valves possibly needing cleaning, I expect it to have typically Toyotary longevity, as long as it gets regular oil changes at least!

If nothing else it'll last longer than the Ford Ecoboom engines  

 

I did find it odd they bothered to, but I guess they felt pressured into making something the same way they're being pressured into jumping onto the EV bandwagon too early, and it serves as a stopgap for people being forced to abandon their diesels but not wishing to fork out the extra for a hybrid.

With the new gen cars,  I think they've finally realized they can leverage their hybrid tech to give the same mid-range push of a turbo rather than designing them purely for efficiency (Which ironically seems to have made them more efficient if my Mk4 is anything to go by    )

 

[Bper]

2 minutes ago, Cyker said:

Generally a turbo or super-charged engine won't last as long as an NA as they are more stressed, as you say, but where everyone else is going for power and putting in too much boost, Toyota engineered the 8NR-FTS to be reliable and only lightly boosted it, so while it doesn't get the headline horsepower figures of a lot of its rivals (Which are misleading anyway), it has a lot more useable mid-range torque and doesn't stress the block as much.

Aside from the valves possibly needing cleaning, I expect it to have typically Toyotary longevity, as long as it gets regular oil changes at least!

If nothing else it'll last longer than the Ford Ecoboom engines  

 

As far more knowledgeable of toyota models and engines have you heard of any issues with this 1.2t 8NR-FTS engine since its launch as I have yet to find any major issues.

As this engine was introduced in 2015 and will be heading towards 9 years old is this not confirmation that this is a reliable small turbo engine and the concerns with small turbos is not always the case

 

[Cyker]

TBH aside from the carbon buildup on the intake valves, I can't think of any common issues with it, but there aren't any of them about, relatively speaking, so it's hard to really know.

I don't often read of any issues with them on here! 

Anyway, there's no reason a car can't be reliable while having turbo - Turbo diesels have been around for ages and tend to be more reliable than a lot of petrols! I think the trick is just to not be too greedy with the boost pressure and that's what Toyota have done, so as you say you have a 9+ year old engine without any major issues as opposed to certain other manufactures who went for power and ended up with leaks and cracked blocks  

[Aygolite]

1.0litre 3-cylinder turbo petrol engines are often sold as a power upgrade to the same sized NA engine.

However, for economy, driveability, and low insurance, it would make more sense to use just 2-cylinders from this engine perhaps even a 650cc 2-cylinder turbo petrol engine producing around 60HP@4,600rpm-5,600rpm and 95Nm@1,400rpm-4,000rpm.

In the lightweight Aygo, a 95Nm engine could be geared for around 20mph/1,000rpm in top gear resulting in maximum torque from 28mph to 80mph.

The problem with the current 1.0litre NA engine, is that maximum torque isn't produced until around 3,600rpm. So with a 20mph/1,000rpm top gear, you wouldn't get maximum torque from the engine until 72mph in top gear which is much faster than an economical cruising speed.

With a 650cc 2-cylinder turbo petrol engine, driven at a constant 50mph you might even be able to get close to 80mpg.