Azrael, The problems your "friend" is experiencing are down to
mapping and nothing else.
I have responded to all emails and questions from him and step by step
he is sorting out the problems with his map.


ECU's ARE complicated products and the S8 is much simplified when compared
with others but still require a level of skill, understanding and experience
when setting them up.


It is unfair of you to blame me for "others" inability to understand how to map
and configure an ecu or failure to understand how engines actually work.


If it was that easy Stu and other tuners would be out of a job.

At the end of the day, no matter who's ecu you use or no matter how much it
costs, it will ONLY be as good as the person tuning it and also how much
time and effort someone is prepared to put in to it.

Most people only think about the full load power mapping but there
are many other parameters needed for example cold start etc...

For your info, the S8 EEC4 plug and play version is actually nearly ready for sale.
It is not available yet due to it being tested in the real world at present
by a WELL KNOWN respected tuning company.
Once they and I am happy with its performance it will be sold - not until then.

It is a shame that not everyone understands the amount of work that actually goes
into a product like these in terms of development.
It is NOT a five minute job.

 

I know I know, that is what I always said - but it is the reason of my question to Stu if mapping different ECUs is very different. The same people build group H engines for Hill-climbing and group A rally engines no problems - so it must be due to some particular difference with working with Motec/GEMS and S8 ECU or some strange failure of this car. Will be looking into that in future.


Simon - you tend to take things very personal. I don't blame you of anything and still think S8 ECU is the way to go in future.


You know - I ain't as stupid as I may seam to you ...


Don't treat it as personal attact or anything like that. But it has been almost ready since I first found passionford - so it's already some time. When we wre corresponding during sammer you were speaking about it becoming avalible to the publick in Autumn I think.


I personally will wait for seeing many happy customers useing it When Idecide to get one I probbaly just drive to Stu's or somebody with lots of Cossie experience.


I do understand what R&D and testing is. You are great at what your doing from what I hear but I get impression from time to time you treat everybody like they were stupoid and unable to understand what your going through and try to make the impression like you weredesigning spece shuttle on your own

More and sense of humore please!

 

i know that there's a lot more to it, but the main question that I would ask is what is the target afr for a range of driving conditions - and you clearly do not want to divulge that invulge which is totally understandable. otherwise all we talk about is things like how to i get a higher afr? bigger injectors or a longer opening duration - things like that.

that's maybe oversimplying things, but what else is there to mapping? you stick some numbers in a table, that's the easy bit. the difficult bit is what numbers and why.

 

So how do you map a brand new rebuilt engine that needs running in still?
Do it bit by bit as it gets run in, put some sort of general purpose map in for running in or just go "sod it!" and give it all

 

Fast Guy,

On the road,
New engines are run in on a map near enough to the spec so they can be driven.
Once run in, the final live map can be done.

On a proper engine dyno cell,
I have dynoed engines using a 3 hour run in process then mapped to full power.
All done in the same day !

 

As Simon says, thats the way its done

If your using me personally and its a wierd spec that IMO can ONLY be lived mapped to get it correct and your engien is new, i will send you a rev and boost limited version to get you up and running safely and nicely, based on a live mapped version of the same. They say a picture speaks a thousand words... This is a real invoice for such a job...

 

Cheers guys


Would you recommend the owner continues his running in after your 3 hours or would you class it as fully run in, cos it beats 1000miles+

 

Fast Guy,

On a dyno cell (not road run in),

The engine is run in on a special "rough" oil to INCREASE friction wear.
The engine is then run at a varying rpm with varying load which increases revs
and load over a period of time usually 2 to 3 hours.
This equates to around 500-800 miles of normal driving.

Then after this period, the filter and oil is changed then the engine is run
for 10 minutes to flush all the rubbish out.
The oil and filter are then changed again, then the engine can be loaded
fully and revved.

All tuners have their own method on the dyno cell for doing this but this particular
method is well proven.

 

 

Stu, looks to me like you want this to continue, so, heres a question.

I believe, though dnt know (am kind of asking ), that when we map ignition, we map it to the point of detonation (heard through the above detcans) - and then back off a little.

What exactly is happening during this ignition advance provoked det? Is it an unstable burn?? or, is it that the burn is fine, and peak cylidner pressures are reached too early (before TDC maybe?)

Thanks, hope this question will heplp others understand a little more about it too

 

Thats a good question Phil, and i "Think" ive already done an essay on it somewhere... brb

 

Ok,
Heres a small explanation i did for another topic but ive altered slightly to make it more suitable for this one..

Detonation in any engine can be caused by a number of things....

1) Excessive cylinder pressures:
This is created by having the maximum PCP earlier than 10deg ATDC. This is of course why we have an advance curve in teh first place, to keep our PCP around the 10 - 20 DATDC area under all conditions.

2) Excessive heat:
Cylinder head and combustion chamber temps can give rise to detonation and far more damaging "pre ignition" (Pinking as you know it) This is simply due to reaching what is in effect the fuels flashpoint.

3) Wrong or poor fuel:
As above, we want a fuel that burns slowly otherwise we will again exceed the PCP target area and cause massively excessive cylinder pressures that will blow holes in things. (Yes, optimax will burn SLOWER than say, sainsburys crap)

4) Excessive advance:
This again is a PCP issue and the first clue you will have is she will feel probably her fastest ever... then boom

5) lean mixture:
Lean mixtures = hotter burn, again taking us across and back to the heat problem. Lean mixtures also burn and flash faster so taking us to the pre PCP area problem.

6) Excessive EGT.
Often created by a combination of teh above. This will put excessive heat into the exhaust valves with corresponding heat and pre ignition problems as desribed above.

7) Excessively hot/cold ICT.
Hot and cold air has an effect on ICP and also AFR. We need to richen as the air cools and lean off as it gets hot. Failure to do so will make our advance curve WRONG. Beware.


And a question from that post that was also relevant to this one in a way so ive left it in:

Quote:

Bosch Man

Detonation in an engine is usually very slight.
A very slight problem will only usually kill an engine if it occurs for a sustained period. So if we have say, det at 5500rpm (common for YB).

In 1st gear flat out she spends maybe, what? 1/4 second there?
In 3rd gear flat out she spends maybe, what? 1.5 seconds there?
In 5th gear flat out she spends maybe, what? 5 seconds there?... Boom.

Hope this helps somewhat.

 

Spot on cheers Stu

 

When mapping, at what % of injector duty do back of?
Some say 75% and also heard of some running 95% even flat out in some applications.

Also some injector calculators seems to be very conservative on hp supllied. Like my 403's only suporting fuel for something like (503 * 4 * 0,8)/5,1= 315 hk
503 cc/min
4 nr of injectors
0,8 inj dutycycle
5,1 fuel consumption under load

I know I have more hk than that

You have a better (maybe more accurate) formula?

Link to site http://www.mrm-racing.a.se/index1.htm

 

I dont like to see the injectors duration exceed 80 where possible unless for very short periods of time. Injector stutter and coil overheating can wreck an engine when pushed hard with high revs, but it has to be said modern injectors are very resiliant, but my professional opinion stands that if you want more power, buy a bigger injector rather than risk pushing your old ones harder. Once the customer understands that that is my view, i will of course do other than teh above if asked.

To calculate injector size required is quite simple really:

First:
Multiply your required Engine Horsepower X your BSFC = (answer 1)

Next
Multiply the number of injectors used x 0.8 = (answer 2)

Now divide answer 1 by answer 2.

Example:
500bhp x 0.5 = 250 (answer 1)
4 injectors x 0.8 =3.2 (answer 2)

250 divided by 3.2 = 78.12lb per hour

So you need to find an injector that will flow 78.12lb per hour at your given fuel pressure and your job is a complete.

That is pretty much it.
For a high comp race engine, figure on around 0.42 BSFC and a low comp turbo lump around 0.55 - 0.65, and you wont go too far wrong.

A good cossie lump can have a higher than expected BSFC and as a result can make more horsepower per Lb than some others, so bear that in mind.

Hope this helps.

 

And how do you work out BSFC (brake specific fuel consumption) exactley? Or is it a rough guess based on previous engines?

 

Evening Wes,
Its essentially an educated guess for an engine you havent Dynod as its based on the fuel requirements for the horsepower developed by the engine.

The brake specific rule of thumb is that your average piston engine will consume 1/2 a pound of fuel per bhp per hour. This is termed .5 BSFC. The best brake number always occurs at peak torque where the engine is opperating most efficiently.

 

It used to be the case that you had to drop the compression for big boost engines.
With all this modern technology can you build a high compression engine with with high boost (for everyday road use,not wrc rally for eg ) and map it to run safely longterm, or is lower compression/high boost still the best bet to achieve big power?

 

still is the case mate

petrol is worse than it was 10 years ago,, and det is still det

 

GARETH T,
Modern piston design techniques DO help to reduce DET
enabling more boost or advance to be used.

(Profiled dish, and piston total seal wear ridges)

Trouble is, MOST people do not seem to look beyond MAHLE and COSWORTH for their pistons.

MY car for example, is CR 8.2:1, can run upto 2.3 bar of boost and the EGT's
are well under control. .

Also, THE comfort zones that tuners use in writing ignition maps can be more
accurate and smaller as ecu technology is more refined now.

You are right, modern petrol is sh*t though

 

been around for many years now though

i do agree

 

slightly off topic.... but along with a new S8 ecu, a monitor would be nice aswell

 

will be building my own. capable of reading sensors directly like original secs monitor (plus addition lambda and egt - 8 analogue inputs in total) and getting readings from S8 over the serial connection. plus will have a built in radio controlled clock and laptimer, 5 programmable shift lights (activated by rpm signal), facility for boost control, gps input over serial connection for road speed, position, direction, height etc. plus datalogging output over serial or can bus.

will be proper bo i tell thee, and less than 200 quid fully built.

 

this is a LONG post now so sorry if its already been asked ...

after seeing the post on the AFR kit i was wondering how much it costs for all of the equipment needed to properly map a car? thinking of it from a business point of view it cant be easy to set up a new business involving mapping. especially without an established reputation as i know personally i would only use a well known mapper as i couldnt afford for them to make a mistake!

 

Well,
If you were model specific, then its reasonably cost effective but if you want to be able to map pretty much anything, it gets expensive, especially when dealing with modern checksum algorythms as you often need 3rd party software to deal with it.

Also depends what quality of hardware you require. Example: That AFR Kit you saw on the other post today would no doubt serve you quite well for a while at Ł400 ish.. where as my industry standard unit is Ł6000+vat.

As with many things, the final answer is "It depends" Ive spent over Ł30K, but i can think of another Ł30K worth of usefull kit i still aspire to purchase... where do you draw the line? LOL

 

it is well possible, and in my experiance high comp engines are lovely to use versus low comp, my own engine is over 9.0:1 and is turboed and mapped to 2 bar of boost by MSD !!

ok so its a rally engine in a rally car , but , driveabilty is a serious key factor to smoothness in a rally car , i dont want the car to be very flat , then all of a sudden a massive boost spike , and if you think that they are lifed , i wouldnt expect to remove an engine for 20 events , thats approx 1800 miles at full flat out power , plus a load of road miles inbetween ,

so if you compare that to a road car which may see that amount of flat out use over what 3 years ??

food for thought !!

 

oh and - evening stu !!

 

30k +30k!! a lot more than i would have guessed then!!

 

Join the club

 

Dunno if you know Stu but the link on your MSD site to this disscusion needs amending.

And whist im here, have/can you live map a new standard clio182 and what would be expected gains?

 

Nick, Sounds like your doing a similar thing to me .

I am about to write a microcontroller to interface a number of systmes on my car.

Essentially it will link my GPS reciever, my S8 ecu, my PDA when in car, and a dash display.

I'll have a perminant VFD dash display showing engine sensors, my GPS unit will be able to work with the display, and my PDA (for tomtom), I will also have the S8 data fed to the PDA (am writing some digi dash/datalogging software for it).

Keep me posted on how yours is doing mate!

 

I look forward to collecting my royalties from both of you.....

 

sounds good phil. keep us posted on yours too.

SECS, nice one. like you pay royalties to autronic etc for building the S8?

 

Stu can you live map the S13 200sx ecu? Think I remember you saying it can't be done but just want to clarify

 

Yes pal, the 1.8s can all be mapped live no problems

 

Stu,

Can i ask, What affect the fuel pressure has on a map???

I was just thinking that the Ecu has no sense or control over it, so therefore what effect would its base setting have on the rest of the map?

i.e. If 3.5 was tested and shown to provide best fueling, what affect would the fuel pressure have on the map if say adjusted to 3.0bar or 4.0bar???

Im assuming that the higher pressure would provide a greater flow rate and the lower a less flow rate, so does that mean it could potentially lean or rich the entire map???

Hope thats not off topic

 

Hi,
Yes, once the map is completed, extra pressure will richen the entire map and less pressure will lean the entire map.

However, when going for extrra pressure you will sometimes lean it off at high boost due to exceeding the pumps flow/pressure capabilities for that given horsepower requirement. Be carefull with excess pressures.

 

Awesome Topic by the way...

Some mre Noddy Questions...

1. Injector Duration - Im guessing its the time the injector is open and closed, and that at the preset pressure set by the reg. flow X amount of fuel. So what exactly are you trying to achieve when you start changing the duration?
What effects can happen?

2. The map itself, does the amount of data equal how accurate the map can be?
For example, if a Map has a Load table that has X number of references, does another Ecu with with twice as many mean the map can be any better???
Or is it that another Ecu which has more Parameters in total provide a better map?

Hope these are aren't too basic for you, but it is monday morning...

 

Im not sure if a basic answer like this is what you want, but we change the duration to alter how much fuel we get.... Its not linear at all, but a very basic example would be.. 8MS flows enough for 8psi 16MS enough for 16psi.. We are increasing the fuel as we are increasing airflow.



Yes, generally speaking the more load and rpm sites available, the smoother and more accurately the engine can be mapped.


Dont worry about me.
If this topic is likely to be active for some time i will shift it back over to gen diss for a while. What do you think?

 

Dont know if it realy matters Stu,

I always log on and check 'Posts since last visit' so no matter whch one its in i'd still see it...

Going back to my Question 1 above.
Day the injectors have a useage band, that is (im trying to word this so you understand what the hell im on about) an area where they are not operating efficiently (under or overuse), i suppose what im asking in a nutshell is, when you say go from standard injectors to 803's, the 803's can flow more fuel at the same pressure as the standard ones, but can this be offset by the duration???
Increase flow on standards and reduce it on 803's....