[Dormermike]

Anyone know why the injectors for the n53 are so much more expensive than the n54?

N53
6 x Injectors with decoupling elements - £1397.81

N54
6 x Injectors with decoupling elements - £566.63

I know it's a bit of a daft sounding question but they both look similar and both are piezo and I know they are not interchangeable (anyone tried?) but just curious to know why.

Perhaps the n53 ones are more precise than the n54 which doesn't run stratified?

Thanks
Mike

[smellypoo]

I saw the same when I was investigating prices, bought an n53-engined 325i a month ago which had a rough idle at cold start, was looking all over at how to get a cost effective fix.

The N54 injectors appear to be quite cheap in the US too, they never had the N53 so perhaps build volumes might be a factor? That's just an idea I had that's probably wrong as the N53 shares the same injectors as the N43.

I ended up paying £588 Inc vat for a very good local specialist to diagnose and replace 2 injectors. It was well worth it, they also confirmed the ones they replaced were index 4 and the remaining were index 11, so running the same across all cylinders now.

The previous owner/their garage probably swapped out injectors until they had it running ok (at the time) - against the common recommendation to replace all injectors per bank if using index 11 ( mine were injectors 1 and 5).

If I did have to replace more, I was tempted to run an experiment with the N54 part all round, just never got that far.

I know it doesn't really answer your question, sorry!

[Phil325i]

According to RealOEM, injectors for the N54 are a completely different part number from the N53, so not compatible...

[RajB]

Be interested to know where you got the prices from as last time I checked a couple of months ago the N54 ones were more on par with the N53 prices you've quoted.

If they have dropped to that price bracket I can only assume it's down to quantities being sold and hence bringing price down perhaps. Still seems a significant decrease.

I might have to ask my parts contact to get a price again.

[Dormermike]

I got the prices from the BMW dealer thread in the sale section of this website.

[Dormermike]

Originally Posted by Phil325i

According to RealOEM, injectors for the N54 are a completely different part number from the N53, so not compatible...

Yep. Just wondering why the cost difference considering they are constructionally similar.

Am weighing up whether to dump my Mondial warranty which is £64 per month plus £250 excess. Car already has latest index 11 injectors so I guess the waterpump, HPFP and NOX are next on the list considering the engine has 52k miles on it. So far the warranty has paid for itself in repairs but the dealer incompetence and all the back and forth is making me think I'll go it alone. Am more than capable, just comes down to cost risk and the n53 is not the most reliable engine out there.

600 quid for a set of injectors is an easier pill to swallow than 1400 quid should index 11 turn out not to be the final design iteration!

[RajB]

Originally Posted by Dormermike

I got the prices from the BMW dealer thread in the sale section of this website.

Ah ok cheers.

[Gaffa22]

Originally Posted by Dormermike

I got the prices from the BMW dealer thread in the sale section of this website.

Hi Dormermike any chance you could post a link or help me find the dealer thread please, I need to buy some injectors

[RajB]

Well I asked the question of Cotswolds and my dealer and both came back with a price of over £1300 for 6 so unsure how they were so cheap at the point.

[Gaffa22]

Have found them in the US shipped and including import taxes for £860

Lots of places in the US do them for circa $110 So why do we get our pants pulled down over here

[Phil325i]

Originally Posted by Gaffa22

Have found them in the US shipped and including import taxes for £860

Lots of places in the US do them for circa $110 So why do we get our pants pulled down over here

If they're from the US, I doubt they're for the N53 because that engine was never sold on the other side of the pond...

[Gaffa22]

they were for the N54

[Dormermike]

Sorry just seen this.

No idea what cars you guys have got so not sure if you're talking about n54 or n53

The price I quoted above for n54 injectors was in the cotswold thread.

[FROSTBURN2020]

Hey bro，n54 injector can be used in n53. i bought 6x n54-12 injector， replace all the 7048-08 in my n53b30. they runs smooth and yields more power than the n53 injectors. if you want to replace them with n54 one，you must replace them ALL.

[Phil325i]

Originally Posted by FROSTBURN2020

n54 injector can be used in n53.

I've no reason to disbelieve you, but I find it puzzling that an injector designed for a turbocharged engine of 225-300hp would work just fine in an NA engine of 140-200hp. Perhaps someone with greater tech knowledge than me can explain...

[Markos ZimZimma]

Originally Posted by Phil325i

I've no reason to disbelieve you, but I find it puzzling that an injector designed for a turbocharged engine of 225-300hp would work just fine in an NA engine of 140-200hp. Perhaps someone with greater tech knowledge than me can explain...

Is the N53 just in the later 325i/330i models? If so the range would be 218-260ish bhp, which is a bit closer to the N54 range.

[therealdb1]

"I've no reason to disbelieve you, but I find it puzzling that an injector designed for a turbocharged engine of 225-300hp would work just fine in an NA engine of 140-200hp."

Probably why Frostburn thinks he has achieved higher power because he's pumping a whole heap more fuel in there.
The injectors are presumably a mechanical fit but without a serious remap I'm guessing it is not the most efficient engine on the road!

As for pricing, parts for most things, not just cars, always appear lower in the US and even after international shipping expensive items can be cheaper to import from America than purchase in the UK. I guess there are more N54 injectors sold than N53 so that pushes down the price. Economies of scale in a global market?

[FROSTBURN2020]

Originally Posted by Phil325i

I've no reason to disbelieve you, but I find it puzzling that an injector designed for a turbocharged engine of 225-300hp would work just fine in an NA engine of 140-200hp. Perhaps someone with greater tech knowledge than me can explain...

bro， n54 injector is black and the n53 injector is grey. the flow rate （number on the left side of oem）is in the same domain.this means the amount of the fuel in the conbustion chamber is in the right domain. that why they can work in the n53.

[0l0dom0l0]

I'll chime in before this gets too speculative. Interested to hear that the N54 injectors work.
Can you confirm no fuel trim faults or codes and does the car switch all the modes - homogenous, stratified etc?

If the injector flow rate was too different, the ECU would throw a code as the short and long term fuel trims would be outside the permitted range. The fuel trims are learned from Lambda in the exhaust and trims are adjusted to keep to the lambda at the target range.

Regarding the 160-200hp bit, you are referring to the N43 2.0 I assume, in which case they are 2.0l and there is only 4 injectors - each cylinder is 500cc. In the 3l engine each cylinder is still 500cc.

Injectors also have a wide range of flow capability, think part load on a turbo engine as full load on a naturally aspirated. It doesn't quite work like that but in simple terms it is good enough for the purpose of understanding this.

I've never been sure what the difference is between N53 and N54 injectors, I assume just a slight flow rate difference if they work okay though...

[Phil325i]

Originally Posted by 0l0dom0l0

Regarding the 160-200hp bit, you are referring to the N43 2.0

No, I was referring to the max and min outputs of the N53 (6-cyl) engines BMW made. And it's 140-200, not 160 (according to Wikipedia).

[0l0dom0l0]

Originally Posted by Phil325i

No, I was referring to the max and min outputs of the N53 (6-cyl) engines BMW made. And it's 140-200, not 160 (according to Wikipedia).

In the E9X chassis in the highest tune (30i) the N53 made 272PS, 268bhp or 200kW, roughly 30hp (25kW) less than the N54 which made made 306ps, 302hp or 225kW.

[Dormermike]

Originally Posted by 0l0dom0l0

I'll chime in before this gets too speculative. Interested to hear that the N54 injectors work.
Can you confirm no fuel trim faults or codes and does the car switch all the modes - homogenous, stratified etc?

If the injector flow rate was too different, the ECU would throw a code as the short and long term fuel trims would be outside the permitted range. The fuel trims are learned from Lambda in the exhaust and trims are adjusted to keep to the lambda at the target range.

Regarding the 160-200hp bit, you are referring to the N43 2.0 I assume, in which case they are 2.0l and there is only 4 injectors - each cylinder is 500cc. In the 3l engine each cylinder is still 500cc.

Injectors also have a wide range of flow capability, think part load on a turbo engine as full load on a naturally aspirated. It doesn't quite work like that but in simple terms it is good enough for the purpose of understanding this.

I've never been sure what the difference is between N53 and N54 injectors, I assume just a slight flow rate difference if they work okay though...

Nice info, pretty much been my thoughts too, as in as long as the flow is not off the scale different the ecu should be able to adapt with shorter injection durations.