20i vs 28i

[Deepseaskateboard]

Has anyone driven both a 20i and 28i?

If so, does the 28 feel like a decent upgrade?

I am aware they are much the same, but the 28 has a different engine map. Not interested in re-mapping or messing with the engine, so would only consider stock cars.

 

[RustyZ4]

I drive the 28i and love it, but you will find a lot of people say they can remap a 20i to get it up to the same BHP, but as you are not looking at doing that, the article below might help with your decision, it old but still relevant

https://www.whatcar.com/news/bmw-z4-sdrive20i-and-28i-review/n8374

 

[sars]

I’m sure there’s more difference between the 20i and the 28i than just a remap, what about brakes and cooling? I’m sure my old 3.0 e89 had bigger disc’s than the 2.3. I’m with the OP and get the more powerful version from the start if that’s what you want

 

[Mr Tidy]

That's a good review in Rusty's link (especially considering it is from What Car). :lol:

I'm with the OP, probably better to just go for the 28i in the first place. No hassle with declaring mods to insurers, and probably more straightforward when you come to sell.

Plus I'm pretty sure the 28i has bigger front brakes.

 

[Anonymous]

I’m sure there’s more difference between the 20i and the 28i than just a remap, what about brakes and cooling? I’m sure my old 3.0 e89 had bigger disc’s than the 2.3. I’m with the OP and get the more powerful version from the start if that’s what you want

The only practical difference is 330mm vs 300mm front discs..as mine was a 20i I did fit the 330mm discs but report no discernible difference in braking...

Full respect anyone not wanting to mess around and I would normally advocate that..but in this case it’s a no brainier and opens you up to some much more choice ..if you figure on £350 to do the ECU remap and £50 per annum insurance you can then do the maths..

I couldn’t find a 28i with the spec and mileage and colour I wanted..

 

[sars]

I’m sure there’s more difference between the 20i and the 28i than just a remap, what about brakes and cooling? I’m sure my old 3.0 e89 had bigger disc’s than the 2.3. I’m with the OP and get the more powerful version from the start if that’s what you want

The only practical difference is 330mm vs 300mm front discs..as mine was a 20i I did fit the 330mm discs but report no discernible difference in braking...

Full respect anyone not wanting to mess around and I would normally advocate that..but in this case it’s a no brainier and opens you up to some much more choice ..if you figure on £350 to do the ECU remap and £50 per annum insurance you can then do the maths..

I couldn’t find a 28i with the spec and mileage and colour I wanted..

Understood, there’s not that many around in that lovely colour, shame really. Is the cooling system identical, as you don’t get something for nothing, more power = more burnt fuel = more heat to dissipate

 

[Deepseaskateboard]

I found the what car review, but you never know what BMW told them to say.

Yeah, the 28 does have bigger brakes, and some other options as standard, but I was just talking about the engine.
There is a constant debate on here if the 18, 20 and 28 all have the same engine parts, I was trying to avoid it!

I understand that many have mapped the 20 for more power, but with my luck it would just end up in an £8,000 engine swap job if it was modified!

 

[JimsZ]

Another happy 28i owner here, went through the same dilema, wanted a range topping 35is and the big power but decided on the 4 pot as I was heading for a longer ££££ commute and its my daily.

Not felt the need to remap either since... over 4 years of ownership with very few issues to report.

My advice is its a great ar in any variant so dont get hung up on too much spec, you will probably have your must have specs but just be prepared to compromise on certain items and you will open up more options.




Even the 330mm Brakes are crap though when the car is pushed so dont lose any sleep over the OEM set up

 

[Smartbear]

I’m sure there’s more difference between the 20i and the 28i than just a remap, what about brakes and cooling? I’m sure my old 3.0 e89 had bigger disc’s than the 2.3. I’m with the OP and get the more powerful version from the start if that’s what you want

The only practical difference is 330mm vs 300mm front discs..as mine was a 20i I did fit the 330mm discs but report no discernible difference in braking...

Full respect anyone not wanting to mess around and I would normally advocate that..but in this case it’s a no brainier and opens you up to some much more choice ..if you figure on £350 to do the ECU remap and £50 per annum insurance you can then do the maths..

I couldn’t find a 28i with the spec and mileage and colour I wanted..

Understood, there’s not that many around in that lovely colour, shame really. Is the cooling system identical, as you don’t get something for nothing, more power = more burnt fuel = more heat to dissipate

Hi Sars, cooling system & intercooler identical. Bmw have engineered the cars for the highest powered variant & the lower powered versions are unchanged
Rob

 

[sars]

Hi Sars, cooling system & intercooler identical. Bmw have engineered the cars for the highest powered variant & the lower powered versions are unchanged
Rob

Thanks

 

[ric19]

I was watching a YouTube Vid earlier with a 28i on a Dyno and it was showing 233 at the wheels..According to this website this equates to 276 BHP at the crank

https://www.mk5cortinaestate.co.uk/calculator4.php

 

[BeardyJon]

I just had my 20i remapped yesterday and I can’t express what a massive difference it has made to the performance of the car. I wasn’t by any means unhappy with it before. But I now understand what people mean when they say a 20i isn’t a true sports car. Until the remap it was the most powerful car I’d owned and I loved the extra pull and grunt over the e85 2.0 sport I had before it. But the remap has taken it to next level. It’s been a great alternative to trading in for a 35i/is and the additional costs involved with that.

I got a Celtic stage 3 remap, which takes it to 280bhp (from 181bhp) and 290lb/ft torque (from 199lb/ft), which puts it above the stock 28i performance. For £295 and £50 per year extra on the insurance I’d say it was well worth the money. Obviously I can’t vouch for long term performance yet, but with as many people on this forum recommending Celtic as there is, I don’t doubt that it’ll be absolutely fine.

The only thing I’ll say is that I may end up burning through rear tyres faster than usual as I get a lot of spin at the moment, but that might just be down to me not being used to how the car drives now.

 

[Anonymous]

I just had my 20i remapped yesterday and I can’t express what a massive difference it has made to the performance of the car. I wasn’t by any means unhappy with it before. But I now understand what people mean when they say a 20i isn’t a true sports car. Until the remap it was the most powerful car I’d owned and I loved the extra pull and grunt over the e85 2.0 sport I had before it. But the remap has taken it to next level. It’s been a great alternative to trading in for a 35i/is and the additional costs involved with that.

I got a Celtic stage 3 remap, which takes it to 280bhp (from 181bhp) and 290lb/ft torque (from 199lb/ft), which puts it above the stock 28i performance. For £295 and £50 per year extra on the insurance I’d say it was well worth the money. Obviously I can’t vouch for long term performance yet, but with as many people on this forum recommending Celtic as there is, I don’t doubt that it’ll be absolutely fine.

The only thing I’ll say is that I may end up burning through rear tyres faster than usual as I get a lot of spin at the moment, but that might just be down to me not being used to how the car drives now.

What tyres / wheels are you running?...where and when are you getting wheel spin?

 

[BeardyJon]

I’ve got Eagle F1 Asymmetric tyres all round on 19” 437M Reps. Rear wheels spin usually when I’m setting off. I think I’m putting my foot down a bit too much.

 

[Anonymous]

I’ve got Eagle F1 Asymmetric tyres all round on 19” 437M Reps. Rear wheels spin usually when I’m setting off. I think I’m putting my foot down a bit too much.

Auto or manual?

Only reason I ask is I never get wheel spin in straight line on a smooth road in a straight line..

 

[BeardyJon]

I’ve got Eagle F1 Asymmetric tyres all round on 19” 437M Reps. Rear wheels spin usually when I’m setting off. I think I’m putting my foot down a bit too much.

Auto or manual?

Only reason I ask is I never get wheel spin in straight line on a smooth road in a straight line..

Manual.

 

[mcbutler]

I found the what car review, but you never know what BMW told them to say.

Yeah, the 28 does have bigger brakes, and some other options as standard, but I was just talking about the engine.
There is a constant debate on here if the 18, 20 and 28 all have the same engine parts, I was trying to avoid it!

I understand that many have mapped the 20 for more power, but with my luck it would just end up in an £8,000 engine swap job if it was modified!

you can easily compare engine parts using realoem..

 

[Smartbear]

I found the what car review, but you never know what BMW told them to say.

Yeah, the 28 does have bigger brakes, and some other options as standard, but I was just talking about the engine.
There is a constant debate on here if the 18, 20 and 28 all have the same engine parts, I was trying to avoid it!

I understand that many have mapped the 20 for more power, but with my luck it would just end up in an £8,000 engine swap job if it was modified!

you can easily compare engine parts using realoem..

That’s still not enough for some people, I’ve seen a response that during a “private discussion“ with a bmw engineer engine differences were revealed even though realoem says otherwise.
Rob

 

[Deepseaskateboard]

I have been on Celtic to see if they would tune the 28 for more power, which would be absurd if they were the same parts.

Got the following results:

18i


20i


28i



So, the 20/28i checks out, not saying this is conclusive by any means. I presume the 18i is an error, unless it has uprated parts!!

 

[Anonymous]

They backed of the tune from 295 to 280 over concerns of pushing it too far..so despite everyone’s secret theory that there are differences there are not many and the 18i 20i 28i can all, with an ECU remap , not an add on box, achieve the same power ..