Chip

iTrader: (3)

Been asked to look at a map for someone, and would love some other people's input, but the person in question (its not someone from this forum) would prefer me not to publish it (its a map he paid for) at this stage

So here is just a single column from the 3500rpm point (wheres its first making good boost), and the scale is versus TPS
Its a turbo motor, and has a seperate table for boost correction

% - Fuel
0 - 28
3 - 37
6 - 36
12 - 48
19 - 66
25 - 77
31 - 88
38 - 90
44 - 87
50 - 88
57 - 83
65 - 87
72 - 87
79 - 89
86 - 88
94 - 87



Ignoring minor stuff like the ve seems to actually wander about a bit where its probably not had much time spent on smoothing it out by the looks of it and the fact it needs more fuel at 3 than 6% and other little bits like that which look like minor errors.

I have one major observation personally that I would deduce from this column, and its this that I would like other people who know a bit about engines/mapping to give their input on:

This is an observation not a critism of anything of course, by 38% the throttle appears to no longer be the bottleneck, ie once you get past that, further opening makes NO difference (makes sense to me, loads of cars are like that as the throttle is a lot bigger than the ports and inlet pipes etc)



Can anyone see a fault in my logic there, before I introduce the Ignition table, or do people agree with that observation?

Before I introduce the ignition table, what sort of trend are people going to expect to see, I dont want gueses at exact numbers as obviously I havent given enough info for you to do so, like CR etc, I just mean the rough trend that you would expect to see of rising and falling during the throttle sweep, like will it alter to a point and then level off? and if so where would you expect that point to be? Or will it keep rising all the way to 94% or will it keep falling all the way to 94%

Literally just the vague shape you expect to see please.

The Youth.

iTrader: (1)

sorry chip no input out of me because all that is way way way over my head!!
mapping all what goes into it, is one of the things I know nothing about and I bet that goes for 99% of peeps on here!
good luck tho

steve

cjwood555

Just a quick one cheap - tps value is obviously an expression of the angle of the throttle butterfly/blade, which is linear, whereas the area available for flow will increase as a complex function, roughly = inverse square.

cjwood555

...so id have thought you'd expect the same levelling off regardless of size of butterely w/r/t ports etc.

RS Grant

iTrader: (1)

I don't know much about this stuff, but I'd also assume that the ignition values are going to follow a similar course as the fuelling.. since the two are related*?


Cheers,
Grant

* are they related?

christophe

Yea I've also found that, on my zetec at low rpms throttle opening of about 30% would be enough to get full vacum, however at 5-6000rpm it would need around 80% throttle to pull full vacum.

I imagine the ignition map would be similar, increasing quickly to start with then levelling out once the VE has bit still maybe fluctuating abit.

Chip

iTrader: (3)

I see everyone expecting the same as me, once we get to the 38% region, as no changes to VE happen above that on the fuel table, you would expect the ignition to follow the same pattern, ie the ignition would decrease until that point then go level.

Here is the actual ignition map.

0 -35
3 - 24
6 - 21
12 -33
19 -34
25 -32
31 -32
38 -32 <-- The point the fuelling levelled off
44 -32
50 -31
57 -30
65 -30
72 -19 <-- why the massive jump here suddenly?
79 -18
86 -18
94 -18


WTF?!

IMHO there is NO way that both those tables can possibly be correct, they just dont go together at all.

rst in breaking

iTrader: (2)

chop as you know i sod all about mapping full stop lol. but with ignition would them fugures just drop instead of going up and down? i.e wouldnt it advance once on boost? could well be way off mark though

Chip

iTrader: (3)

Paul, this is nothing to do with boost, thats on a seperate table.

AlexF

Fuel table seems ok - if a little rough...


Is the Ign table in degrees?!?

Alex

RickyLee53

Chip, can you post the full tables, what ECU is it on?

The ignition map is certainly wrong, surely he looses power by pressing full throttle!

But, I mapped a car recently which was turbo but had ITB's similar to a pulsar. They went waaay past 100% the way the inlet had been designed it made it very hard without expensive work to correct. I did the best I could, (which didn't fix it) then I told him i couldn't do it.

In the end I did it and the map was pretty funky, I wouldn't give him all the power he wanted till he sorted the problem.

Chip

iTrader: (3)

I'll see if the lad will let me at some point, but TBH its all pretty much the same story as this snippet.

Off boost yes, but on boost though as far as I can work out its probably ok for timing at full throttle but will det its fucking tits off at part throttle as it hasnt got enough timing taken out by the boost compensation table, so at half throttle he's got a map still giving him about 25 degrees of ignition at peak torque at a bar of boost, IME these engines want about half tha, which is then like he has at full throttle at the same point while flowing the same amount of air as demonstrated by the fuel table!

The engine, rather unsurprisingly, has melted, lol

Chip

iTrader: (3)

The whole table is rough, its got figures jumping up and down and generally looks like it was done in about 10 minutes flat by someone who hasnt got a clue.


Yes

rst in breaking

iTrader: (2)

i stand by what i said then, i know absolutely nothing about the subject, thought i may have understood something then..... but i didnt lol

rog

iTrader: (2)

I can see what you mean from the tables above roughly, i don't know alot about mapping, but all i can suggest is that if you try and understand the parameters that may effect the ignition, and are effected by, this may have some bearing on why it is like this???? God knows, just my "technical analysis"

AlexF

You comment about the engine melting doesn't surprise me...

I guess theres retard on boost but even so thats A LOT of advance for an A-series let alone somthing with reasonable VE.

Alex

Chip

iTrader: (3)

I understand the parameters just fine mate, its the person who "mapped" the car that appears not to.

Chip

iTrader: (3)

Its an LET engine, compression ratio up in the 8s, cossie inlet, T34


But like I said, its not the values that shocked me, its the thought that anyone could believe they had finished mapping (and charge the customer) while the two tables for fuel and ignition have NOTHING in common with each other in terms of how they see the VE of the engine!

rog

iTrader: (2)

Cool, so what parameters effect the ignition, and what does the ignition change in turn effect???? Just to enlighten me, as i admittedly know f*ck all about this.

Chip

iTrader: (3)

The ignition picks up a base value from this table.
Corrections are then applied.
The main one being from the boost table, but there are also corrections for things like intake temp.

AlexF

It is very odd lol

Perhaps he doesn't own det cans

Chip

iTrader: (3)

I assume he does, its a fairly well known tuner with his own rolling road.

And I also assume he does as the values at full throttle seem ok, which I assume means he used det cans to work them out, so if it was only ever driven at full throttle it probably never would have melted
He obviously just never ran it up at half throttle at any point, and also never stopped to think about what would happen ignition wise if he did!

AlexF

Well your narrowing down the mapper LOL

ian sibbert

I was looking at another thread on a rally site where a tuner was trying to purport that everything apart from the flat out figures were irrelevant, as it was a 'race' engine. I am so glad i'm not in the tuning industry as there seems to be so many poor tuning companies who basically rob people and give the industry a bad name.....

I honestly think a lot of these people dont understand the basics of how an engine work...let alone how one responds to turbo charging....

The timescale people tell me they have had there cars mapped in seems astonishing...

Chip

iTrader: (3)

Its not meant as a name and shame, I just wanted some other people's input to confirm or deny what I am saying so that the fella in question could see its not just me that can see this sort of thing at a glance, it should be obvious to ANYONE who knows the basics about mapping!

Chip

iTrader: (3)

I know what you mean, Rob on here with his astra has mentioned (on the mig vauxhall forum) a couple of times about us doing bits of mapping on it, and people replied "thought it was already mapped, my mapper only takes a couple of hours to do the whole map, why do you need to keep doing it"

People like MSD need your car for a week in order to map it properly, as they need to do multiple cold starts etc, how anyone thinks you can fully map a car in a couple of hours is beyond me!

Jim Galbally

i have a basic understanding of mapping, and i would concur with you that those tables do not make sense.

unless ofcourse there's some amazingly clever compensation tables going on that do some wierd and wonderful things that would make us all go "WOW, now thats a genuis at work" but somehow i doubt that

jammerrs

now i have no idea about mapping but an engine needs more fuel for 6% that 3% throttle deffinatly

dont realy understand what they show though

Jim Galbally

jammers, not necessarily.

just in this case it does seem more likely that its just wrong... lol

Crowder

not mapped by someone down my way is it...? lol

RSturboJET

I don't understand why the map is throttle based. It just doesn't make sense on a turbo engine.

Most maps are MAP or Air Flow based and the TPS used for enrichments unless its got throttle bodies.

Using this TPS map and boost compensation maps etc. only complicates things.

The fuel map should rise, peak and fall in a smooth curve and the ignition map should fall with more load

Garage19

Actually it makes alot of sense to have TPS with a MAP correcction or TPS with a MAP blend.

If the MAP correction allowed it i would have re scaled the main TPS load.

I would imagine this ecu to be a an Emerald?

markk

iTrader: (2)

lol

I read that also - very shocking

Chip

iTrader: (3)

Garage19, yes its an emerald, I'll get some screen shots of the whole tables as the lad says he doesnt care if it gets posted, think he isnt going to bother trying to sue them or anything he's just going to learn not to go there again!

Chip

iTrader: (3)

Been given permission to post the whole map and mention who mapped it, so here are the 3 main tables.

Company who "mapped" this was JDM : http://www.jdm-dyno.com/

clarke5700

im sure thease were the people that maped luca's zetec turbo fiesta

Chip

iTrader: (3)

NO

That is JKM this is JDM

Totally different company mate, just a similar name! JKM IME are very professional.

3i_gaz

they mapped a friends corsa LET and hes never had an ounce of trouble with it and it gets abuse on every outing

clarke5700

o i see lol

Chip

iTrader: (3)

They must have done a better job on that one than this one then, either that or its the same map but he hasnt driven his at half throttle yet, lol!

Not called Barnes is he by any chance?