OrionRST200bhp

iTrader: (1)

as im going down the stage 3 route what should i do with my ecu should i get rid of it altogether with my stage 1 chip inside or is it easy enough to just unplugg the chip and keep the ecu for the stage 3 chip? i dont know anything about the cossie ecu. thanks in advance

Eagle

iTrader: (2)

cosworth ecu is a chip in and out jobbie.
takes 5 mins to do

R5FORD

iTrader: (1)

going stage 3..

get closed loop

OrionRST200bhp

iTrader: (1)

whats involved with that then mate? i know fook all about cossie ecu's

davidreader5

Hi,
Late saph and escort coSworth with l8 and p8 had closed loop, tighter emission on later cars, early none cat co 3.5% limit and later cat 0.5%. when you modify
the engine this is when problem arise, with the cosworth weber marelli.
the management l8 & p8 doesent have enough sites in the map to have tighter control of the emissions test, for off boost and cruise fuelling,
MSD stu and kenny have designed a way of controlling the emissions on a l8 or p8 ecu modified engine, to pass mot catalyst emisison tests. the fuel ratio
is close to 14.7 1 parts air to 1 part fuel by weight, = lambda 1, closed loop control by the help of a lambda sensor, the engine comes out of closed loop
for example when you come on boost (under load conditions) and will not be closed loop when the car engine is cold temp, i dont know what stu from msd
has done to enable the cars with l8 /p8 to pass the tighter emissions with for example 803 green injectors which you would use for stage 3, maybe he has found a way of adding more map sites for more control. there have been reports of people with now modified engines higher than stage 3, getting 30,mpg, out of a cossie? so i would if funds permit go for msd;s closed loop conversion also because they have a good rep for mapping beside having there closed loop option, ps i think parts wise you need 02, = lambda sensor and chip for conversion to closed loop, then parts for your stage 3, setup which depending can be actuator for turbo, injectors 803's, 3,bar map sensor, maybe different turbo and intercooler depending on funds, std fuel pump normally upto the job, although msd will check, and chip already mentioned, usually set to run approx 24psi peak boost.
depending on turbo.

Regards Dave R.

foreigneRS

davidreader5 it's got nothing to do with number of map sites, it's a closed loop if an injector duration of x ms is too much fuel as indicated by the reading from the lambda sensor, it will try y ms and so on until it gets a lean signal and then goes higher again

OrionRST200bhp

iTrader: (1)

thanks mate that explains alot

Twellsie

iTrader: (1)

and as yours J plate it should already have a lambda sensor fitted, its the little plug on the top of our down pipe

OrionRST200bhp

iTrader: (1)

yea mine does have lambda its was pluged into the top of my turbo.

gingeRS

itll probably need replacing if the cars been chipped cos the older chip would have not used it and cos they run so rich they get fooked

not too dear though, i got mine from GGR for 50 quid

i have closed loop and see 30mpg, and you should have seen the mot testers face when he saw 0.9% on the CO meter

KSA-Cossie

iTrader: (4)

Drop stu at MSD an e mail m8 or better phone him,you'll have l8 ecu and lambda set up as standard .

cozmeister

iTrader: (1)

[quote="gingeRS"]I don't have closed loop, and my mot tester normally passes out from the richness of the mix long before the machine takes a reading

davidreader5

Ok NICK, yes what you have said is how a normal lambda sensor works,
ie the ecu uses the o2 sensor in closed loop to control the fuel mixture
the result is a constant change from lean to rich, and with the cat keeps the emissions correct,
an 02 sensor will generate 0.9 volts when the mixture is rich and there is hardly any unburnt oxygen in the exhaust, and when the mixture is lean the sensor higher oxygen in the exhaust the voltage is low say 0.1. and when the mixture is balanced ie 14.7.1 or lambda 1, typically 0.45 volts
just to clarify when the ecu gets a rich signal 0.9 volts, off the 02 sensor it weakens leans the mixture, and when the 02 sensor shows lean low volts 0.1 monitoring burnt or unburnt fuel by o2 level.
the ecu richens the mixture, etc and also other things can effect the function
such as air temp, throttle position, air leak in exhaust.
Back to the msd conversion i only guessed, i said i dont know what they have done to achieve there closed loop control level with large injectors
over std DO YOU.

foreigneRS

i've struggled to read your post to be honest david, what with the random presses of the return key to jump to a new line when you haven't even finished your sentence

you've not told us anything new there really. you said before that you think that the lambda control for larger injectors may need more map sites - i'm saying it has nothing to do with the map as it just runs a completely different strategy when in closed loop. it doesn't run off the values in the map as it doesn't need to.

it needs to start somewhere with a base injector duration from the map, but then it just uses the feedback from the lambda sensor to know whether it's rich or lean. if rich, use less fuel. if lean, use more. the calculation of how much to use is standard closed loop control circuit feedback stuff known as PID. for different sized injectors, you just need to optimise the PID settings so that the control behaves as you want based on the feedback from the lambda sensor.

hope that helps

davidreader5

Nick, its not that hard to follow, my essay, just found a review in a cosworth special edition mag, describing msd's closed loop, and it says without writing the whole page,
The reason for overfuelling high emissions
such as 7% on some engines with a legal limit of 3.5% 0.5% on post 93 cat equipped cars, is due to the std L8/p8 management system doesent have the required amount of MAPPING SITES to allow the off boost fuelling to be properly set?. so if what you've said is so simply that theory is based on normal lambda control with std setup engine spec, it would be easy to just modify the engine with large injectors 403's etc, without bore wash in some cases.
By letting the lambda control sort the closed loop fuelling, so why have msd put a lot of time into finding the solution to give good emissions to pass mot std test with high hp engines, some how they have made the ecu more efficient more intelligent, as said above my point is the mag says not enough map sites, i can upload the page if required, maybe your friend at rp labs can enlighten you & me,my PID is parameters ID as in obdII, also the msd conversion has better mpg than the std cosworth l8/p8 car. as there conversion has more control over the injectors.

best regards Dave R.

R5FORD

iTrader: (1)

in simple terms mate it makes fuel last longer if driven sensibly

get in touch with stu @ msd

OrionRST200bhp

iTrader: (1)

R5FORD

iTrader: (1)

sorted mate

foreigneRS

davidreader5 the magazine is wrong

nothing has been done to the ecu to change the number of "mapping sites" - the L8 came out of the factory with lambda control enabled. as far as i know, all that needs doing to cope with larger injectors is tuning of the PID characteristics of the closed loop control.

the ECU just runs a set of instructions. it will have a set of instructions in it that say if the water temperature is high enough and the throttle pot is at rest, i.e. the engine is idling, then use the closed loop control to give the correct fuelling for lambda control. if these parameters are not met, use the values from the map.

similarly, in cruise mode it can use closed loop control, until such time as the boost or engine speed or whatever goes outside of the values in the instructions and then it uses values from the map.

i know perfectly well how closed loop PID control works, i use things everyday that i have programmed to use this method in the control of the climatic wind tunnel that i run

i think that you need to go off and read about it, here's a link

http://en.wikipedia.org/wiki/PID_loop

davidreader5

Here is part of the mag page mentioned, so performance ford have got it wrong have they?, i checked out your link also it quotes Note that the use of algorith for control does not gaurantee optimal control. but if you do it for a living you should know pid, pity you did'nt know law monitor as well when nik recommened you. going by the mag make your own mind up as to the confusion.


Dave R.

foreigneRS

the magazine is wrong i'm not even going to bother replying to you anymore. i've heard it said that you can't educate pork

Stu @ M Developments

iTrader: (12)

Im sure this can be re-solved more ammicably....

What part of the article are you reffering to?

davidreader5

Nick, hit a nerve have i, dont spit your dummy out, i'll take you off my christmas card list then,


Best regards Dave R.

Stu the part of the article that is being discussed if you can call it that, is how did MSD convert the l8/p8 to give good emission that pass the mot with cat post 93, with high hp engines, that have good control over the larger injectors such as 403's. in performance ford they quoted that there was not enough map sites for fine enough control, in the pages above we have discussed how closed loop and open loop works, now i said i think it was not enough map sites, before i found the mag article, nick jumped in and condemed my reply, which i dont mind, just wondered why performance ford article was not corrected before printing,

As you and kenny are the creator i was hoping you would come on site and clarify how you achieved your conversion of closed loop modification to the l8/p8. it would if you had the time make a good topic sometime.

Dave R.

Stu @ M Developments

iTrader: (12)

Ok,
Bit busy now and i can see the point of confusion, and, interestingly, you are BOTH correct.

I recall the original article stated that there are not enough load sites to make the engine run stoichiometric in all the right places when using large injectors, and that is 100% correct, we simply dont have enough to allow us to interpolate between teh few we do have with enough accuracy and kleep the fuelling both top and bottom of interpolation correct.

However...
What nick seems to be saying as that closed loop does not add any extra load sites, what it does is put the fuelling under PID control, which is of course also correct. But PID doesnt add any sites to teh map, it simply takes the original mapo and adds and subtracts injector opening time as required to see stoichiometric output at the exhaust. In a nutshell, it fixes the lack of load sites problem, without adding anymore at all, it simply adds another algorythm in closed loop control which means the original fuel map no longer has to be perfect.

Hope that helps, if not, i will clarify further.

gingeRS

my car just sailed through the MOT (day before she was picked up by her new owner )

legal limit for CO 3.5% actual 0.6%
legal limit for HC 1600ppm actual = 394ppm

lambda = 1.003



closed loop is very clever and well worth it....so much so, the guy suggested he may get the car rechipped by his preferred tuner, and i asked to buy the chip back, if this is the case

foreigneRS

Stu @ M Developments properly cleared up

davidreader5

Thankyou stu, as you agree would be nice sometime to do a more in depth topic of the subject for those im sure interested, as very good conversion for people with modified cars at M O T time, and also give's good mpg
regards Dave R