Area under the graph comparing real world performance of engines
JamieZ4C said:Are you sure, Rob? It literally says NM on the graph! Am I missing something?!Smartbear said:The torque axis is in ft-lb’s, 30i makes 228 of them
Looks like there’s 2 different measurements plotted on the one Nm axis there, it should nominally be 30i at 228ft/lb compared to the 20i making just under 300ft/lb
Rob
ronk said:
Sounds a bit over dramatic there Ronk, the 2.0i range is based on the 28i which makes over 240bhp in standard form.
Mapping an n20 engine for an additional thirty odd bhp is hardly “wringing it’s neck” as you put it, it’s only a modest increase which shouldn’t compromise reliability.
Rob
Attleborough, Norfolk
Smartbear said:JamieZ4C said:Are you sure, Rob? It literally says NM on the graph! Am I missing something?!Smartbear said:The torque axis is in ft-lb’s, 30i makes 228 of them
Looks like there’s 2 different measurements plotted on the one Nm axis there, it should nominally be 30i at 228ft/lb compared to the 20i making just under 300ft/lb
Rob
Ever since his yellow peril disappeared of his signature poor old Pete has been slipping.
Another good reason to bring it back.
A
Anonymous
Guest
Ed Doe said:
To clarify a few points...
We’re not comparing a turbo diesel vs a NA petrol engine..we are comparing a latter day designed turbo petrol engine vs it’s outgoing NA predecessor...
The substantial extra torque and bhp at the same rpms shows why BMW did it...plus they got better emissions..
Much more torque lower down allowed both short shifting on the box and better economy plus equivalent outright performance..
It was the next generation..
A
Anonymous
Guest
BTZ461 said:
The bhp curve was for a 3.0 litre N52 in the same state of tune, stock, as fitted to the E89..
The headline dyno bhp and torque figures matched closely BMW’s published figures so is as close a set of numbers to allow an apples for apples comparison..would be pointless otherwise..
I don't really understand choosing a Z4 as a car for its low running costs. The N20 makes sense if you just want a cheap to run "A to B" car to fill with kids and shopping but why on earth anyone would want to pick one in a toy car is beyond me.
That argument becomes even more illogical when you spend money putting bigger brakes, upgraded exhaust and an ECU tune on it. You've still only ended up with something that only has 90% of the performance of a completely stock 35i and still doesn't sound as good.
The turbo I6 is more than economical enough for me. If they offered a turbo V8 I'd be driving one of those instead rather than trying to justify having the 35i by saying I don't need the power :lol:
That argument becomes even more illogical when you spend money putting bigger brakes, upgraded exhaust and an ECU tune on it. You've still only ended up with something that only has 90% of the performance of a completely stock 35i and still doesn't sound as good.
The turbo I6 is more than economical enough for me. If they offered a turbo V8 I'd be driving one of those instead rather than trying to justify having the 35i by saying I don't need the power :lol:
enuff_zed said:R.E92 said:
So you're just on a different horse and a different course.
The majority of these discussions just come back down to personal preference.
It seems we are all happy with what we have. That's good enough.
I get that. Some people only need a donkey to get around their local racecourse but this entire thread is about trying to upgrade a donkey.
If you have a donkey and that's all you need then no problem, but it's cheaper to just buy a horse if you suddenly decide you want a horse rather than feeding your donkey steroids.
R.E92 said:enuff_zed said:R.E92 said:
So you're just on a different horse and a different course.
The majority of these discussions just come back down to personal preference.
It seems we are all happy with what we have. That's good enough.
I get that. Some people only need a donkey to get around their local racecourse but this entire thread is about trying to upgrade a donkey.
If you have a donkey and that's all you need then no problem, but it's cheaper to just buy a horse if you suddenly decide you want a horse rather than feeding your donkey steroids.
So you didn't 'get that' then. Or your particular nag is blinkered? :roll:
Would it be easier if I just said yes yes everything you say is gospel and applies equally well to me?
Horses for courses, different budgets and backgrounds etc mean we cannot all afford to purchase and run the top of the range models and that’s why we all drive different versions. For me even with my upgrades it still has worked out much cheaper than coughing up for a 3.0 six pot or a 28i N20, and because of budget the 3.5 variants were never a consideration. And what I like is my little 18i punching above its weight and giving the big boys a run for their money
enuff_zed said:R.E92 said:enuff_zed said:So you're just on a different horse and a different course.
The majority of these discussions just come back down to personal preference.
It seems we are all happy with what we have. That's good enough.
I get that. Some people only need a donkey to get around their local racecourse but this entire thread is about trying to upgrade a donkey.
If you have a donkey and that's all you need then no problem, but it's cheaper to just buy a horse if you suddenly decide you want a horse rather than feeding your donkey steroids.
So you didn't 'get that' then. Or your particular nag is blinkered? :roll:
Would it be easier if I just said yes yes everything you say is gospel and applies equally well to me?
I'll simplify it.
You said horses for courses.
I agreed with the sentiment of your input but pointed out that this thread is not about people being happy with their choice, rather it's a thread devoted to justifying the choice by modifying it.
It’s all down to personal choice and I’m relaxed about that - but the thread seems to be based on a justification of how I can make a 2.0l 4 as fast as a 3.0l 6 - you don’t need to justify yourselves!
The evidence is there for all to see that is quite an easy task to do just that - but it wasn’t my choice.
Once you’ve squeezed the pips out of the smaller engine then that’s ya lot! You have a well tuned engine near its limits and I wonder who would buy a remapped car with 90k on the clock?
Not my choice, but each to their own
Ps RE 92 just beat me to the “justification” theme!
The evidence is there for all to see that is quite an easy task to do just that - but it wasn’t my choice.
Once you’ve squeezed the pips out of the smaller engine then that’s ya lot! You have a well tuned engine near its limits and I wonder who would buy a remapped car with 90k on the clock?
Not my choice, but each to their own
Ps RE 92 just beat me to the “justification” theme!
R.E92 said:
I think we'd agree to differ on that.
For me it was a conscious choice to buy the N20-engined car, with a plan in mind to map it to produce exactly the machine I wanted.
I believe that may be the case with several other owners.
After many disparate threads on the subject, I thought this one was started by Pete to explain the reasoning behind his, mine, and a few others' choices. He has done a lot of research to get to this point in a logical manner and is merely presenting a set of bald facts from which interested readers can make their decision. I do not believe his intention is to influence that decision.
At the end of the day, if someone likes to cruise with more than adequate power in reserve, whilst listening to that great straight six soundtrack then every graph in the world would not change their mind.
Comments written without face to face interaction can be misconstrued, and if I have the wrong end of the stick I apologise. Initially, to me, your input came across as decrying all Pete's work and telling us all we are just striving to justify why we stupidly didn't by the 35i/iS in the first place.
Cry heretic if you will, but I actually looked at a few of them when the cash was in my pocket and careful thought told me I didn't need that particular model to satisfy my requirements.
I have commented elsewhere how nice my wife's 2.5i M54 engine sounds, but that is NA. I listened to Stevo87's 35iS a few weeks back and 'personally' didn't think it sounded as nice as the NA one, which has an un-enhanced purity to it.
enuff_zed said:
Don't get me wrong, I like seeing Pete's topics, they generate some good discussion and a bit of sub-model rivalry is a normal part of any model specific forum. This thread is about comparing a mapped N20 to an N52 so it's only a continuation of that logic to present the idea that anyone purely interested in a torque curve might want to consider the N54 shaped elephant in the living room.
I do think that Pete would certainly appreciate the N54 though. He seems to have a keen interest in the engineering aspect of vehicles and evidently enjoys a bit of power.
Turbo engines with peak torque arriving earlier and extending for longer are always going to have better real and perceived acceleration than the equivalent NA motor with a similar peak power output.
But frankly who cares? The whole idea of having a car like the Z4 (or other roadsters) is for the soul and for the al fresco driving experience. If you really wanted just power then buy something else. In the same way, if you wanted a car to handle properly, buy something other than a Z4 rather than trying to make your Z4 handle better.....
For me, the whole concept of the Z4 is as a GT car which happens to have a roof that folds into the boot. It's good at eating miles in reasonable comfort and style but it falls a long way short in terms of an overall driving experience. But, again that misses the point. If I wanted a Boxster/911 Cabrio (etc) then I would have bought one. Rather I wanted a car that was relatively good value and had a peach of an engine in terms of how it delivers its power, and importantly how it sounds and deals with NVH. So, while a Turbo 4 might be much better (and they are) they completely fail the emotional test. Witness the reaction to the flat-4 718 Cayman/Boxster - they have had to put the flat-6 in the back of the GT4 to regain some credibility.
And while on a roll to upset the four pot crowd, everybody (even non-petrolheads) say to me "doesn't the engine sound nice" or from BMW aficionados "it's got the right engine in it, hasn't it." You can't beat that even if your 0-62 time is 0.5 seconds off the pace.
But frankly who cares? The whole idea of having a car like the Z4 (or other roadsters) is for the soul and for the al fresco driving experience. If you really wanted just power then buy something else. In the same way, if you wanted a car to handle properly, buy something other than a Z4 rather than trying to make your Z4 handle better.....
For me, the whole concept of the Z4 is as a GT car which happens to have a roof that folds into the boot. It's good at eating miles in reasonable comfort and style but it falls a long way short in terms of an overall driving experience. But, again that misses the point. If I wanted a Boxster/911 Cabrio (etc) then I would have bought one. Rather I wanted a car that was relatively good value and had a peach of an engine in terms of how it delivers its power, and importantly how it sounds and deals with NVH. So, while a Turbo 4 might be much better (and they are) they completely fail the emotional test. Witness the reaction to the flat-4 718 Cayman/Boxster - they have had to put the flat-6 in the back of the GT4 to regain some credibility.
And while on a roll to upset the four pot crowd, everybody (even non-petrolheads) say to me "doesn't the engine sound nice" or from BMW aficionados "it's got the right engine in it, hasn't it." You can't beat that even if your 0-62 time is 0.5 seconds off the pace.
R.E92 said:
It’s a double edged sword though, no one would deny the n54 has the potential for shed loads of power but you then move further away from the n20 cheaper running costs which are part of its appeal in the first place.
That’s why it has its fans because of the sweet spot of economy/power/cost it inhabits, you alter one of these items & it’s easy to upset the balance of the Apple cart. Just imho of course.
Rob
We know that the 6’s last to many many miles - it would worry me how a re mapped motor will be when it gets older. That really can’t be predicted without a high degree of strip/measure/re builds
Nobody has shown an opinion on the purchase/sale of a re mapped car.
I have a hunch that the value and saleability might be effected. I suspect there’s going to be a few “returns to stock settings” in a few years time
Nobody has shown an opinion on the purchase/sale of a re mapped car.
I have a hunch that the value and saleability might be effected. I suspect there’s going to be a few “returns to stock settings” in a few years time