Bmw 320is S14B20 Engine increase power

[Magmotor]

Hi everyone,

I'm Automotive Engineer student and i will use my 320is to my course project. So, i need some help.

I will start to build the engine but i need the to buy some pistons, my questions are:
If it's better to buy the original ones and finish the engine like the OEM, or show i buy a wossner pistons?

Later i will probably buy some new cams to increase torque, so, can i buy the wossner pistons now with no problem about the valve tolerance or any other problem?

When i have time (€) to buy new cams, what do you recommend? I prefer more torque that power, because i want to use the car for some amateurs rally's.

Another question is about the ECU, i want to buy a Megasquirt, take of the AFM, change the ignition to wasted spark or individual coils, and use sequential injection.

That's my priority questions, but if you have more suggestions of what can i change to improve my can in general, they we'll be welcome.

How wants to help me in my challenge?



Thanks in advance.

[hardtailer]

I would get aftermarket pistons if I plan on running different cams at some later point just to prevent buying pistons twice.
The original pistons dont allow a wide choice of cams, so aftermarket pistons become necessary pretty quickly. I am not sure if tuning for torque (instead of power) offers more chance of keeping the original pistons but I doubt it.
I would also reconsider tuning for torque as the 2.0l S14 is not the torquiest of all the S14 versions. Instead it loves to rev so I'd make use of that (i.e tune for power)
I'd tune for power and get the right diff ratio (and gearbox ratios) to get torque at the wheels.
Bottom line is: plan what you want from the engine considerig its use and the available budget and if you can only achieve this wiht aftermarket pistons then get those.

Re Megasquirt: a few on s14.net run it. I have too but the tuning process was put to a halt due to a engine rebuild necessary because of wear not damage.

Tuning the ignition is very hard without a rolling road or a good knock detection system. Tuning the fuel is quite easy using a wide band oxygen sensor.

[Magmotor]

Now my engine need to increase power and torque.
I will disassemble and rebuild it.

What the S14 engine experts recommend me to do?
What parts should i buy to build a reliable engine to use in track days and hill climb races?

Thanks in advance.

[jeff]

The best mod for increase torque is to stroke to 84mm or 87mm.
If you have cc limits the best mods are: schrick cams 284/276 if you prefer torque, or 292/284 for power. It's better to go to aftermarket forged pistons (11,5:1 max) because with stock pistons + 284/292 cams it's probable that valves touch the head of pistons.
Porting the head to 28/28,5mm max and work the ITB and black rubbers at the head side to have a near constant shape with head inlet.
Don't work the exhaust of the head, it's perfect!

Here you are near true 210Hp.

These are the best price/power mods, you can also buy a carbon airbox but are near 900/1000$ for 2/3Hp...
From the electronic point of view I've experience that the only sensible gain is going to an EFI / Motec / Microtech (you can reach up to 5/8Hp and better usable torque), but they're expensive. If your goal is to spend less money tune the stock Motronic and change the diff from 3,46 original one to 3,90, your car becomes really aggressive!

[Jake]

I was at a bit over 220 whp with Evo 3/2 cams, no porting, stock TB's, 46mm airbox & Maxx Automotive Alpha N. Stock internals.






Jake

[france320isco]

Hi everyone,

I'm Automotive Engineer student and i will use my 320is to my course project. So, i need some help.

I will start to build the engine but i need the to buy some pistons, my questions are:
If it's better to buy the original ones and finish the engine like the OEM, or show i buy a wossner pistons?

Later i will probably buy some new cams to increase torque, so, can i buy the wossner pistons now with no problem about the valve tolerance or any other problem?

When i have time (€) to buy new cams, what do you recommend? I prefer more torque that power, because i want to use the car for some amateurs rally's.

Another question is about the ECU, i want to buy a Megasquirt, take of the AFM, change the ignition to wasted spark or individual coils, and use sequential injection.

That's my priority questions, but if you have more suggestions of what can i change to improve my can in general, they we'll be welcome.

How wants to help me in my challenge?



Thanks in advance.

Hi. I'm a 10 years mechanical engineer.
First of all ask yourself how many 2.0l naturally aspirated engine outputs 180/190hp nowadays, without variable valves systems.
Do some search, not many i suppose, i still have to find one, but i'm sure it exists.

Then, fix a power increase target.
Due to what i said above, the motorsport engineers did a hell of a job so the possibility of coming up with a power decrease is very high.

The best and safest tune is to install m3 e30 push rods and cranckshaft, but i don't know what is your final course project purpose.
The aftermarket pistons often slaps, the best are the stock mahle ones.

I did something with MAF tuning:

http://www.youtube.com/watch?v=Ft2UzKq41MI

but obvoiusly, as the most of the systems which are supposed to increase the intake flow just removing the AFM, the effect is negligible.

[france320isco]

I was at a bit over 220 whp with Evo 3/2 cams, no porting, stock TB's, 46mm airbox & Maxx Automotive Alpha N. Stock internals.






Jake

The tests you posted make me able to say something else which is related to what above stated.
In point of fact all the alfa-n, general tuning and things like that offer always poor/negligible results.
An engine produces obviously torque, not power. Now, let's compare the torque.
We have here three test outputting from 155 to 158 lbft which is 210 - 213 Nm and the stock torque is 210 Nm as reported e.g.
http://www.bmwe21.net/?page_id=173 so the torque increase is plain negligible.
The power increase is only due to the max rpm at which this maximum torque is available ~6000/7000 rpm while it is 4500/4900 in thestock engine.
The only noticeable effect in this engine tune is the cam tune, which has not increased the filling (as can be obviously expected if lift is untouched) but only shifted the maximum filling.
So the engine is just "shifted" and i hope that the owner doesn't drive always @6000/7000 rpms.

I have also to remark something that is often not considered at all.
If one is going to obtain a better filling at some rpm range, like with a higher lift and/or head porting, the second step is to enrich the mixture at that rpm range.
More air / more fuel = more torque.

About A-N systems.
There are really big evidences on the net (and they have been around for years now) that alpha n systems are useless because as i always remark, you can't get more of 2l of air in a 2l bottle by simply enlarging its neck :soccer:

[Jake]

What do you think you're looking at france320isco? That graph just shows three runs of the same engine. It is not to compare different engines or modifications.

If you want to argue this, then lets start with the correct graph.





The fact is, the modified engine is faster. Period.

Jake

[france320isco]

What do you think you're looking at france320isco? That graph just shows three runs of the same engine. It is not to compare different engines or modifications.

If you want to argue this, then lets start with the correct graph.





The fact is, the modified engine is faster. Period.

Jake

Don't be disappointed, i'm not selling anything, nor i want to "argue" it is just a techinal "basic" consideration.
I knew (i understood from your message) that those were three tests on the same engine, maybe i didn't make myself clear.
In point of fact i compared them to stock as you can see.
On this other graph we have a torque increase from 200.16 to 214.65 (if i got it right) which is the 7.2% (stock 210Nm - all the more useless with respect to it 2.2%).
So, again, the tuning was useless and, as far as i can see, the % gain is so low that it is probably inside the dyno bench error which is not indicated (each measure "on earth" is error-affected) we have just a "correction factor" but no indication of the range on the measure and about what is being corrected: 1% - 2% - ...4%? On what? Torque? Speed? Power? All of 'em?
Now if the error was in the same direction and of the same value in both tests, well, one can reset it by making the difference between the results, but it never does, so an indication of the "standard" accuracy vs power and/or torque (maybe given by the bench maker) is always to be provided.
From the three tests above 213/210 = 1,4% is ~ the maximum bias, but it doesn't say anything about the error (it maybe only say that statistically it is always in the same direction which could make the +7,2% a "true" result).
Well it is not so easy to have two identical test, one should need a climatic chamber.

Surely the engine is faster (in wot condition, nothing can be said about the pt behaviour) and the outputted hp is greater, no doubt about it, the maximum torque is outputted @6751rpm, as i stated above (4900 - 5000 stock) this is probably related to the cams work and i still hope that this car is not driven @ that speed 24h a day .
But it is not outputting more torque, it is just available at higher rpms.
One could see the effects on torque by making some mixture adjusting in the 6000 / 7000 wot map: if all the work has given "more air" in that range one should see more torque (at least a +10%!!! vs stock or vs intial condition).

Now, to make a comparison, 30Nm is the torque outputted by the human leg on the bycicle pedal, just to understand the order of magnitude.

And about the second picture: valleys, mountains...A smoothing via some noise filtering (also via an error estimation) would be welcomed!

All this is just to say that an engine IS torque, nothing more, nothing less.
The motorsport engineers set it in the 4000/5000 range, for driveability purposes maybe, i don't know.
Here we have to wait >6700 rpms (7240 -> rev limiter). Maybe something related to the "i want it higher" which is personal choiches, nothing to argue about it.

The alpha n CEO have a plot of a 320is with only alpha-n installed that reports a +20Nm gain. Even if it is not a "marketing" dyno test you can find online similar results with just eprom chipping.
I told about the "marketing dyno" cause there are evidences (at least on a lot of forums) that the an system ONLY (forget the gruppe A motors) is not a great deal for engine gains.
And, if it is not tuned properly, it is a plain disaster, simply because the stock engine was designed for ITS OWN INTAKE PATH.
But again, this is obvious, given some easy physical principles (the bottle ).

[Jake]

I realize that English is not your first language and I'd never hold that against anybody. But unfortunately, it is preventing me from truley understanding your points.

You've rambled on about this concept before. You're passionate about correcting people on some kind of concept relating to how power gains are described. If I've translated your comments well enough, to me it seems to be a very moot point.

Ultimately, the modified engine is faster and produces more power in the range that it is used. For the record, that engine was used mostly between 6000 - 8000 RPM. The tuning, airbox, removal of the AFM, cams etc... all made that engine much more enjoyable. Nearly 40hp and 11ftlbs at peak.

Regarding your analogy of the bottle neck and AFM and how they do not determine the volume of the container. It completely ignores the factor of time. The size of the bottle neck totally affects how FAST you can fill that bottle.

A change to Alpha N but nothing else (AFM still in place) will not offer true gains. Not sure if that's what you're trying to say. But remove the AFM (because it is no longer needed), and the engine will produce more power at any given RPM.

Install one of these DTM/Grp A replica air boxes and again, there will be power gains. I don't know why you consider them to be negligible, but that is just an opinion. In my opinion, and many others, the gain is more than negligible.

The plot change from one run to another was the result of the engine coming up to temp on the runs you see above. We repeated the test until the engine was fully up to temp. Once everything is stabilized, peak numbers didn't change more than 1.2hp.

It is clear you have not tried these modifications yourself. The gains are real and the engine is faster. For whatever reason some people with no experience like to say this does not work or its negligible. I don't know, maybe to sound smart. Eventually these people are ignored.


Jake

[france320isco]

I realize that English is not your first language and I'd never hold that against anybody. But unfortunately, it is preventing me from truley understanding your points.

You've rambled on about this concept before. You're passionate about correcting people on some kind of concept relating to how power gains are described. If I've translated your comments well enough, to me it seems to be a very moot point.

Ultimately, the modified engine is faster and produces more power in the range that it is used. For the record, that engine was used mostly between 6000 - 8000 RPM. The tuning, airbox, removal of the AFM, cams etc... all made that engine much more enjoyable. Nearly 40hp and 11ftlbs at peak.

Regarding your analogy of the bottle neck and AFM and how they do not determine the volume of the container. It completely ignores the factor of time. The size of the bottle neck totally affects how FAST you can fill that bottle.

A change to Alpha N but nothing else (AFM still in place) will not offer true gains. Not sure if that's what you're trying to say. But remove the AFM (because it is no longer needed), and the engine will produce more power at any given RPM.

Install one of these DTM/Grp A replica air boxes and again, there will be power gains. I don't know why you consider them to be negligible, but that is just an opinion. In my opinion, and many others, the gain is more than negligible.

The plot change from one run to another was the result of the engine coming up to temp on the runs you see above. We repeated the test until the engine was fully up to temp. Once everything is stabilized, peak numbers didn't change more than 1.2hp.

It is clear you have not tried these modifications yourself. The gains are real and the engine is faster. For whatever reason some people with no experience like to say this does not work or its negligible. I don't know, maybe to sound smart. Eventually these people are ignored.


Jake

I think that you understood perfectly what i was pointing out.
I'm not passionate in correcting people and i wasn't correcting anybody, i actually say what i think about what i read, i don't live on opinions, I don't have to appear smart in a forum on the web, i can be ignored too, i can live with that, that's all.
In my message you just see what you wanted, that's ok.

But you didn't read carefully, in fact i told you twice that the engine was faster and that the "filling time" or efficiency had increased in the 6000/7000 rpm range (the bottle fill faster) and that it was, to me, due to the cams work (twice). But that (torque shifting) was the major effect of the tuning.
If it was the purpose, and if the owner is happy with his $/gain% ratio, ok. I don't know. I don't care. This is not the point.

The unnerving (i know that for someone is unnerving for others not) point is the comparison between the "gain by simple chipping" and the A-N +/- cams +/- other things is available online. The fact that the gains are similar it's just simple physic to which I'm simply stuck, no opinions, just physic. Physic which i'm not going to repeat there (maybe doing someone a favour) 'cause i don't want to be "passionate in correcting".
The real bottleneck of each engine in the world is what in Italy we call "valve section". The intake / exhaust path is only used to shift the torque via a well known experimental formula which i'm not going to repeat (i'm not so passionate).

For the rest, where you say that i have no experience (10 years engineering, 5 in close contact with the automotive engineering testers and designers) and in answer to your opinion about alpha n systems: it's true, i'm not an s14 tuner professional, nor an engine designer and i'm not and will not ever going to test useless (TO ME) modifications, but i strongly suggest you and everyone that is interested, to read some basic knowledge engine design books, cause the answers (experimental ones, not theory and equations) are just there and have been there in the last 30/40 years, driving the real designers mad, trying to get a good compromise between torque, power, driveability.
And, again, not referring to any of us, i suggest a different approach, way more low and less self celebrating.

The only way to certainly and undoubdtely increase torque is to increase CC and work on the a/f ratio, it's not my fault, it's chemistry.
So, if you want more torque, buy an s14b23/b25 or do some "CCing".
http://en.wikipedia.org/wiki/BMW_S14.
240/210 = +14.2%.
Now, to me (and that's MY OPINION, undeveloped, unevolved and barely conscious, passionate in correcting and IGNORED smart appearing pro) if i had spent thousand dollars (€) to see less than 230Nm @ 5000rpm on a 320is i'll be asking my money back (w/o success obbviously).
And that's because the torque gain has to be comparable in the same rpm (stock) range to see something interesting.

But this thread exists to answer a student who wants to increase torque/power in a roughly 100hp/l engine, na.
I say, fix a target and pay attention.
To your wallet, first.

Now, Jake, i don't know you, i don't know what you do for a living, i don't mean to correct you, like anybody.
If you work as a tuner i'm pretty sure you do the right things and you always asses your customers needs to satisfy them the best way you can.

P.S. I can't find the logout button...

[Jake]

You use the word "passionate" negatively. It is a positive thing in my opinion and that was how I meant it.

Its hard to understand what your overall point is. First I thought you wanted to prove that we are not gaining torque because this is a function of crank throw length. Can't get more torque without increasing physical dimensions of the lever (crank). I understand, but you didn't just say it like that. You went on to talk as if people had a big misunderstanding of how torque is made. But people were not making any big mistakes that required this long and somewhat random explanation.

So then I thought maybe you were trying to say changing to Alpha N is useless. But in fact there are advantages. So I'm not sure if you are just choosing to ignore them to make a point. All very confusing how you explain your points. Maybe that chipping costs less and has similar results as Alpha N? Ok, so what? Getting rid of the AFM allows you to make more power at a higher RPM. That ='s fun. You don't like that because you don't like to drive your engine that high? Ok, suit your self.

Maybe you wanted to make a point that most people don't understand engines and this makes real engineers mad. Who cares? We are talking about ways to make an engine faster. That is the original question. So people made some suggestions and the real engineers around the world are now so angry because someone suggested Alpha N, cams, and different intakes? Can those things make an engine faster? Yes. So what is the problem?

If everything is about your wallet, why are you even into S14's? They're expensive and old. Buy a cheap Mazda and have fun for much less $$.

I am not a tuner. I do not have customers. I do not own a business. I'm just a guy who likes to play with his car. My job? I am a helicopter mechanic.

Jake

[france320isco]

You use the word "passionate" negatively. It is a positive thing in my opinion and that was how I meant it.

Its hard to understand what your overall point is. First I thought you wanted to prove that we are not gaining torque because this is a function of crank throw length. Can't get more torque without increasing physical dimensions of the lever (crank). I understand, but you didn't just say it like that. You went on to talk as if people had a big misunderstanding of how torque is made. But people were not making any big mistakes that required this long and somewhat random explanation.

So then I thought maybe you were trying to say changing to Alpha N is useless. But in fact there are advantages. So I'm not sure if you are just choosing to ignore them to make a point. All very confusing how you explain your points. Maybe that chipping costs less and has similar results as Alpha N? Ok, so what? Getting rid of the AFM allows you to make more power at a higher RPM. That ='s fun. You don't like that because you don't like to drive your engine that high? Ok, suit your self.

Maybe you wanted to make a point that most people don't understand engines and this makes real engineers mad. Who cares? We are talking about ways to make an engine faster. That is the original question. So people made some suggestions and the real engineers around the world are now so angry because someone suggested Alpha N, cams, and different intakes? Can those things make an engine faster? Yes. So what is the problem?

If everything is about your wallet, why are you even into S14's? They're expensive and old. Buy a cheap Mazda and have fun for much less $$.

I am not a tuner. I do not have customers. I do not own a business. I'm just a guy who likes to play with his car. My job? I am a helicopter mechanic.

Jake

Ok on the "passionate".
I was only trying to help a student in deciding what target was good for its work (torque shifting? torque improving? @ what rpms?) and, due to the fact that he was going to use his own money, to pay attention to the risk/reward ratio. This is important even if you are rich, cause to be rich doesn't mean to waste money.
To do this i made an example with your plots which is a poor results, BUT ONLY IF ONE WAS EXPECTING SIGNIFICANT (>10%) TORQUE GAINS.
If one was expecting torque shifting @ high revs and a little torque gain, that's a nice work (and the aplha n sound it's fantastic).
I tryed to explain that this "poor resulting" happen in the great majority of the cases (not always) when you're tuning the intake (lenght, volumes...), the exhaust or cams and the need for a consequent A/F ration adjustment adds another variable to keep in count.
I was also pointing out the importance of having in mind what kind of an engine you are looking for in terms of power delivery, which relates to the torque shifting and, if you are going to drive @6000/7000 rpms, the importance of, maybe, taking some other steps to guarantee the reliability (i know that someone out there is convinded that an s14 can get to 10000 rpms w/o major modifications, but if the designers did set the rev limiter to 7250 rpm i think it was for a good reason like valve/spring resonances).
Last but not least, the big challenge that a nearly100hp/l engine is for the tuner, so, if you want to push a 2l engine to an output greater than 220 Nm and near the 240 Nm @ 4500/5000 rpms which is a 2.3l...Good luck!

Regarding the alpha-n topic i only argue on the fact that some sees it like the promise land of wonderful gains, while a 100hp/l simple can't be restricted (if one doesn't what to know the Bernoulli principle it's ok). There have been experiments, like these: http://www.maxbimmer.com/forums/show...t=8224&page=2: which only prove simple physic. If they are fake or due to a bad a/f tuning, well i don't know.
Here is the results showed by the A-N CEO compared with a simple chipping.
As you can see the torque gain is now interesting (quite miracolous), but "comparable" with the chipping. So we have, again, the $/reward ratio to pay attention.



I've never understand if that a-n car have had other major tuning than the a-n only.
I've also experienced other "a-n only" dyno tests on other forums which experienced torque losses but power gains due to the torque shifting effect.
I wasn't talking about lever/cranck, it wasn't about engine kynematics, it wasn't about judging people engine knowledge.

My general purpose, when it happens, is just to warn the "satisfied customer" about the lack of data (error bias, etc.) of any dyno test which it's showing "power gains".

I could also change my attitude like: "oh, wonderful, perfect, what a marvellous tuning, etc."
If one day i'll be watching a dyno test where the a-n only vs AFM stock gives +20Nm everywhere in the torque range...I'll now that even a 100hp/l engine can be restricted.

[Jake]

Good explanation. Thanks for taking the time to provide good input. Much more clear this time.

Jake

[france320isco]

Good explanation. Thanks for taking the time to provide good input. Much more clear this time.

Jake

Thanksssssssssssssssss