Comparison of the 2.0 Turbo N20 Engine with the B48 Engine

[NotePapa]

Greetings everyone, I am considering a 125i equipped with the 218 hp N20 engine.

There is much bad information on this engine, including oil consumption attributed to inadequate valve seals and rings, coolant leakage, and timing chain problems; hence, I am rather apprehensive.


I recommend acquiring a vehicle with a comprehensive BMW history; however, such options are almost nonexistent within a £10,000 budget.

Are they really so detrimental? What should one be vigilant of, among other considerations?

Opinions?

[MutanX]

Indeed, they are substandard; also, as you have said, they experience crank end float, which damages the pistons. Refrain from engaging with them, since their adjustments are not worth the inconvenience.

[NotePapa]

Indeed, it seems to be the later B48 engine used in the 230i. Vehicles begin at £15,000; I presume they are satisfactory?

[MutanX]

Not really had anything to do with the later B48 so cannot really comment on them.

[HeadlinesQuick]

Consider a 2016 or newer low-spec 20i equipped with a B48 engine and remapped to 250 bhp.

The market is saturated with 20i models. However, the subsequent engine is regarded as a pocket rocket and is highly sought for, thus commanding a premium.


I purchased a 420i around seven months ago. I searched for a few of 430i models, but the costs increased significantly.

[NotePapa]

I am seeking a 1 or 2 series, preferably not a 3-liter model. The most economical option is the 230i, priced at £15,000.

[HeadlinesQuick]

I am grateful for it. I sought a 330i or 430i and had no interest in a 3.0i engine.

The 2015 and later B48 engine variants, namely the 20i and 30i, are identical engines with just factory tuning differences.
A multitude of 120i vehicles is available on the market, and they may be effortlessly remapped for substantial power enhancement.


The 2 Series is rather pricier than the 1 Series; thus, you may need to restrict your options to the 120i within your budget. If the budget is severely constrained, consider a Cat N vehicle that includes comprehensive documentation of pre-repair and post-repair conditions, executed to a high degree. Those automobiles may be £2,000 less expensive in comparison.

Unfortunately, the costs of secondhand cars are now exorbitant. I sought a little Toyota Yaris for my father within a £5,000 budget; however, the majority of available vehicles were subpar for that price, particularly for a Japanese mini.

[HeadlinesQuick]

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[CleverPixel]

When searching for a vehicle, always use Vcheck. It has been often referenced here and costs just £10, making it the most comprehensive check available. A substantial discussion on this issue started some years ago, highlighting that this check identifies aspects often overlooked by others.

[depofly]

B48s are sufficiently aged to display some issues. Intermittent failure of chain guides and accumulation of junk in the Vanos central bolt gauze filters. I saw a 2016 320i with 38,000 miles requiring a gearbox and engine repair, namely the chain, guides, and Vanos gear.
This matter is very complex; yet, not all instances present issues. Low mileage and a clean interior are essential, accompanied by frequent oil changes.
Modifying the N20 2.0 to achieve 250 horsepower often results in catastrophic failure when a piston fails. The 28i has reduced compression for a specific purpose. The B38 three-cylinder engine is rather delicate. Although not exceptionally quick, an F30 320i B48 performs well and offers a pleasant driving experience with the 8-speed automatic transmission.

A B47 diesel is a superior option.