Performancing Tuning for 20i - Will it kill reliability?

[rafcom]

Hi All

So it seems there is a local company selling those Stage 1 160Kw and Stage 2 180Kw mods for the N20 at a very reasonable price and I'm very tempted to give it a go (wouldn't mind a smidge more torque).

I'm assuming it's simply a boost increase with fuelling updates, and I know technically the 28i pushes 180Kw, so it's realistically "doable". The question is, how would that affect the 20i in the reliability department? I'm really enjoying my Z so don't want it grenading on me any time soon.

Thanks,
R

 

[matsmith749]

Any change is done at your own risk (duh) - but the fact is that the engine in the 20i is offered by BMW themselves in varying states of tune, so it is one of the safer upgrades you can make.

Many many have done the same, with few issues.

If you stick within the bounds of what BMW has done with the other variants, you should be absolutely fine.

It's not a 'smidge more' BTW - it is a complete transformation.

 

[B21]

I’d advise against off the shelf updates for the N20 unless they stay say within 28i limits…

If you want more (265-285 BHP) then I’d suggest an expert on n20 with a rolling road..

Reason being that the HPFP on early ones was weak and it can then run lean just where you don’t want it..

Also EWG cars perform better / differently to PWG cars..

I do a full oil/filters/plugs before you start..depending on mileage maybe coils..

 

[rafcom]

Well honestly, I was thinking of only going up to Stage 1 (160kw/215hp) but from what I've read thus far I might as well do Stage 2 (180kw/240hp). I did however notice that the 28i has lower compression pistons and it seems to have a small secondary radiator. Would running the same HP without those cause any issues? Bearing in mind, we are a "warm weather" region and down at the coast where I live we have 95 octane petrol.

I run a Bimmerlink dash, will have to see if it can show me AFR.

 

[B21]

Well honestly, I was thinking of only going up to Stage 1 (160kw/215hp) but from what I've read thus far I might as well do Stage 2 (180kw/240hp). I did however notice that the 28i has lower compression pistons and it seems to have a small secondary radiator. Would running the same HP without those cause any issues? Bearing in mind, we are a "warm weather" region and down at the coast where I live we have 95 octane petrol.

I run a Bimmerlink dash, will have to see if it can show me AFR.

Incorrect..the N20 fitted to the 18i/20i/28i was physically identical in all markets…

240 BHP would be a prudent limit without recourse to ‘proper’ tuning..

 

[Deepseaskateboard]

Well honestly, I was thinking of only going up to Stage 1 (160kw/215hp) but from what I've read thus far I might as well do Stage 2 (180kw/240hp). I did however notice that the 28i has lower compression pistons and it seems to have a small secondary radiator. Would running the same HP without those cause any issues? Bearing in mind, we are a "warm weather" region and down at the coast where I live we have 95 octane petrol.

I run a Bimmerlink dash, will have to see if it can show me AFR.

Do you have a source for the lower compression pistons and radiator?

Would be interesting. The general consensus is that all the engines are the same...

 

[Pondrew]

Do you have a source for the lower compression pistons and radiator?

Would be interesting. The general consensus is that all the engines are the same...

I have heard this several times aswell. I wonder if there is confusion with the early B48, as I understand they came in high compression and low compression variants. And also have a water-cooled intercooler. My B48 has two coolant reservoirs!

 

[B21]

Well honestly, I was thinking of only going up to Stage 1 (160kw/215hp) but from what I've read thus far I might as well do Stage 2 (180kw/240hp). I did however notice that the 28i has lower compression pistons and it seems to have a small secondary radiator. Would running the same HP without those cause any issues? Bearing in mind, we are a "warm weather" region and down at the coast where I live we have 95 octane petrol.

I run a Bimmerlink dash, will have to see if it can show me AFR.

Do you have a source for the lower compression pistons and radiator?

Would be interesting. The general consensus is that all the engines are the same...

There is a lower compression n20 engine called 28i..it was never fitted to E89s

 

[rafcom]

I've read it in a few different places, which of course I can't remember, but here is a mention of the lower compression from a quick search ... https://bmwtuning.co/n20-tuning-potential/

Here is a diagram of a cooling system with a secondary radiator ... https://tinyurl.com/N20-Cooling-System ... but I recall seeing something on a Youtube video as well.

 

[B21]

I'd focus on the cam chain issue if reliablity is a primary concern

 

[B21]

I've read it in a few different places, which of course I can't remember, but here is a mention of the lower compression from a quick search ... https://bmwtuning.co/n20-tuning-potential/

Here is a diagram of a cooling system with a secondary radiator ... https://tinyurl.com/N20-Cooling-System ... but I recall seeing something on a Youtube video as well.

Parts from 20i and 28i are identical

https://www.realoem.com/bmw/enUS/showparts?id=LL31-EUR-03-2011-E89-BMW-Z4_20i&diagId=11_4770

https://www.realoem.com/bmw/enUS/showparts?id=LL51-EUR-01-2011-E89-BMW-Z4_28i&diagId=11_4770

 

[rafcom]

I'd focus on the cam chain issue if reliablity is a primary concern

Speaking of which, is there an easy way to tell if the chain and guides have been replaced?

 

[B21]

I'd focus on the cam chain issue if reliablity is a primary concern

Speaking of which, is there an easy way to tell if the chain and guides have been replaced?

Yes peer through oil filler cap..if cam chain guides are a white colour then it’s new ..brown/dirty oil colour old..