2.5i The Same Engine As 2.5si?

sharpyboy · Post by **sharpyboy** » Thu Mar 23, 2017 1:11 pm

I Vaguely remember reading somewhere the facelift N52 2.5i engine (177bhp) is the same engine as the N52 2.5si (218bhp), is this correct? what gives it the extra bhp, is it just different software in the ecu? Is it possible to upgrade this in th 2.5i for the extra bhp?

Post by **srhutch** » Thu Mar 23, 2017 2:09 pm

Same engine as in N52, but different components. Not just an ECU upgrade.

step_change · Post by **step_change** » Thu Mar 23, 2017 4:55 pm

How do you know which BHP engine you've got? I know mine is a N52 but other than that.....

BradleyB · Post by **BradleyB** » Thu Mar 23, 2017 5:08 pm

step_change wrote:How do you know which BHP engine you've got? I know mine is a N52 but other than that.....

If your Zed is the 2.5si as your sig suggests then you'll have the 218bhp engine

Smartbear · Post by **Smartbear** » Thu Mar 23, 2017 5:39 pm

I know the USA market gets a lower powered 3.0 car with the n52 engine, it misses out on the 3 stage DISA airbox for its electronic castration

Mike6 · Post by **Mike6** » Thu Mar 23, 2017 5:47 pm

And dont forget the prefacelift 2.5i (SE) with 192 bhp which I have. I have asked the question before about possibility of upgrading between the 177 bhp, the 192bhp and the 218bhp and no one seems able to say exactly what the differences are. Unless one has bigger valves, higher compression etc I would have thought differences would be ancillary like induction, injectors etc which would be easier to change.

Smartbear · Post by **Smartbear** » Thu Mar 23, 2017 5:52 pm

Mike6 wrote:And dont forget the prefacelift 2.5i (SE) with 192 bhp which I have. I have asked the question before about possibility of upgrading between the 177 bhp, the 192bhp and the 218bhp and no one seems able to say exactly what the differences are. Unless one has bigger valves, higher compression etc I would have thought differences would be ancillary like induction, injectors etc which would be easier to change.

The prefacelift car has a completely different engine (m54 v n52) so could never be "upgraded" to si power.
Rob

Mike6 · Post by **Mike6** » Thu Mar 23, 2017 5:54 pm

Ah thanks Smartbear but there is a 218bhp SI version of my engine.

Smartbear · Post by **Smartbear** » Thu Mar 23, 2017 5:59 pm

Mike6 wrote:Ah thanks Smartbear but there is a 218bhp SI version of my engine.

The n52 isn't a version of the m54, it wasn't made until 06 onwards.
What year is your car?
Rob

Mike6 · Post by **Mike6** » Thu Mar 23, 2017 6:15 pm

My car is early 2005. Its the SE but the badge on the car says 'i'. I am sure there was also an Si version available with higher bhp

Post by **srhutch** » Thu Mar 23, 2017 7:48 pm

Mike6 wrote:My car is early 2005. Its the SE but the badge on the car says 'i'. I am sure there was also an Si version available with higher bhp

No, pre facelift are M54 only. Facelift (2006 onwards) with 177 or 218bhp using N52 engine.

SE is trim, nothing to do with I or Si.

Facelift was available as SE or Sport with either a 2.5i or 2.5Si so giving 4 possible combinations.

step_change · Post by **step_change** » Fri Mar 24, 2017 10:12 am

BradleyB wrote:
step_change wrote:How do you know which BHP engine you've got? I know mine is a N52 but other than that.....

If your Zed is the 2.5si as your sig suggests then you'll have the 218bhp engine

Thanks man!

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