Best Regards

Fredrik Lindqvuist

Sweden

Best Regards

Fredrik Lindqvuist

Sweden

Has anyone any idea where I can get one new or second hand.

Many thanks
Mark

Cant see your email, so i cant reply there.

After almost a year with the si i can safely tell you that it moves with utter respect. The power comes beyond 3k rpm until 7.300rpm. Even filled with luggage it should not trouble you at all and its performance is admirable. I never had a problem with it.

Its no 335i however and i think that you are mixing things up. This car is a homologated 320si and should remain as is. No superchargers, no motor transplants, no upgrades, not even new wheels…nothing. Thats why there is no supercharger kit or a respectable ecu upgrade. If you are thinking a 335i motor i think you’d be better off buying a used 335i.

The 320si’s advantage besides its exclusivity is the way it handles with its lower center of gravity and lighter chassis that no 335i with stock susp can corner like that.

For more info, you can find me at bmwforum.gr under Nikos320si.

Thx for the comment!

Regards,
Nikos

Thanks, Pericles

Thanks, Pericles

Here you can see real carbon black.. my car ;)
http://moje.auto.cz/rarsch/esicko.html

Reliability is a relative term, ie, to what engine are you comparing the reliability of the S14 ??, what was the usage of the engine you’re comparing it to ??. Are we comparing engines of the same era late 80s vs 90s vs 2000s ??, is the S14 engine you’re using as a reference stock or is “upgraded” ??

Remember most of S14 owners do see track time or at least auto-x which also is at different levels of stress to the engine.

Most of the failures of the S14 comes from either not properly maintaining them or because they’re seeing a lot of track time which increases odds of failure. Common failures of the engine itself comes from lean conditions which leads to detonation, which could lead toa spun bearing, which is probably an expensive failure.

Causes for lean conditions are commonly intake leaks and because of the independent throttle bodies setup on the S14, there are more seals, o-rings and hoses that can potentially fail and allow more un-metered air into the engine, hence an lean condition, hence potential disaster…

What also might happen is that there is a design flaw in which S14s suffer from oil starvation on high Gs right hand turns. That will lead also to oil starvation. For that there is an oil pan baffle that needs to be in place and that was developed just after the car was put in the market.

There are many users of S14 with more than 200,000 miles and still going strong.

As for the cost, yes, they’re expensive to fix, it’s just economies of scale. Only around 17,000 E30 M3s were produced, compare that to all of the other M3 engines and you’ll know why it’s expensive, and let’s not throw the other regular 3 series engines in the mix…

As for my E30 M3s personal experiences, my Sport Evo is still going strong at almost 60K miles, a previous US E30 M3 I had is still going strong with the new owner after 100K miles and my race car project did have a spun bearing failure.

As I mentioned before, it’s probably related to cost and the finance guardians inside BMW that is preventing this engine to be all it can be, at least on street trim, or even more, an entirely different engine more suited to racing.

Look at previous homologation engines like the S14B23 from the 2.3 E30 M3 and S14B25 of the Sport Evolution E30 M3. Those engine were/are VERY reliable and the Sport Evo engine was almost at the 100 HP/ liter mark WITHOUT VANOS and without clever DME (Engine Management System) since electronics were not powerful in those days, late 80s.

The N45B20A from the 320si for sure could have been better in terms of power output, it could have benefited from a single throttle body intake ala S14 and maybe more aggressive cams. They could get away with emissions figures by different programming at the DME level.

One thing I just looked up were some of the N45B20 specs, ie, bore 85mm, stroke 88, compression ratio 11:1, Max Permissible Engine speed 7,300 RPM, Permissible constant engine speed: 6,500 RPMs. Head Valves diameter: 35mm intake, 30mm exhust.

This will make the N45B20 an under-square engine. This means the ratio between the bore and stroke is less than 1. (Ref: http://en.wikipedia.org/wiki/Stroke_ratio) The only advantage of having an under-square engine compared to an over-square one is more torque at lower RPMs and better fuel economy. Under-square engines are LESS reliable in terms of wear, they have smaller head valves due to smaller bore, hence, less flow through the head, hence less output potential and lastly they’re heavier and taller.

All S14 engines from the E30 M3 were over-square (93.5mm bore x 84mm stroke), (Sport Evo: 95mm bore, 87mm stroke) Vales were 37mm intake (38.5mm Sport Evo) and 32mm exhaust with sodium filled ones for the Sport Evo.

What does this all mean ??, that because of cost, BMW didn’t WANT to build a SPECIAL 2.0 engine for the WTCC that uses a different block, pistons, crankshaft and head than the regular E90 4 cylinder engine. They just wanted to keep the cost lower by sharing engine components with the regular E90 4 cyl engine

From the engineering stand point, they could have just taken the S14 to a new level, give it VANOS, give it the powerful DME and for SURE they will have a better engine for the WTCC and hence, the homologation version for the street…

As usual, corporate bean counters getting in the way of true engineering, shame on them….