MarkD chip FTW

[gravyface]

slapped that lil nugget of goodness into the ECU this afternoon, big difference past 4500,  getting up to highway speeds was less of a chore; down low around town not much of a difference in performance but the car feels like it's running better/smoother.  

Probably put about 60km on it since the chip swap, but I've read that the ECU will take some time to "adjust" to the new chip.  Can someone describe this process in a bit more detail?  I'm curious if this is in fact true and/or what's actually happening at this point.

[bmwconnect]

Yes MarkD has some nice chips and does alot of great work. Anybody that tells you it takes time for a OBD1 performance chip to adjust doesn't know what they are talking about. however OBD2 Car's are more complex and can learn with adaptions

[bmwconnect]

The DME can adjust but not in the way most people think. It does not store memory of your past driving events at least not for OBD1 car's .
The fuel map is always used with a Lambda system. One common but false saying is that the fuel map is no longer used when the car is equipped with an Lambda sensor. This is far from the truth. Where does the original fuel value come from? Is it a guess? No. Any change in load or engine rpm, the DME must go to the fuel map to get its initial value. Then the fine tuning begins.

[Warsteiner]

bmwconnect, maybe you can chime in on the DME trying to compensate on these bigger injectors 21# or 24# that everyone is dropping in and not making any changes to their chip tuning.  What is the DME really thinking and doing?:-) Can it adapt?

~Ralph

[bmwconnect]

bmwconnect, maybe you can chime in on the DME trying to compensate on these bigger injectors 21# or 24# that everyone is dropping in and not making any changes to their chip tuning.  What is the DME really thinking and doing?:-) Can it adapt?
~Ralph

21~24lb is not a huge increase over stock, naturally the car run's well on start up and loves the extra fuel on warm up. Once the O2 sensor kicks in it will see a rich condition and try and trim the fuel down witch is does very well and cycles this process millions of times over while at part throttle(Closed LOOP)  . When you hit WOT the car go's to OPEN LOOP and grabs fuel from a single map 1x16 resolution. these cars seem to love a 1-2% increase in fuel threw the whole rev range thus making the injector upgrades feel nice with a cold air intake or a better breathing system

[bmwconnect]

Can it adapt?

~Ralph

Put 30LB injectors in and tell me if it adapts

[bmwconnect]

Thanks

[Romrog318is]

21~24lb is not a huge increase over stock, naturally the car run's well on start up and loves the extra fuel on warm up. Once the O2 sensor kicks in it will see a rich condition and try and trim the fuel down witch is does very well and cycles this process millions of times over while at part throttle(Closed LOOP)  . When you hit WOT the car go's to OPEN LOOP and grabs fuel from a single map 1x16 resolution. these cars seem to love a 1-2% increase in fuel threw the whole rev range thus making the injector upgrades feel nice with a cold air intake or a better breathing system

actually 24# is pretty large over stock and will end up flooding the engine unless your run higher than 93 octane fuel with a WAYY advanced timing... also with my M52 i cant run 24# unless i get a custom chip or tune for them because its just too much fuel.
also with a mark D chip its designed for the STOCK injectors and not BIGGER injectors and plus the stock injectors are already oversized enough ther 19.5# i believe

[bmwconnect]

actually 24# is pretty large over stock and will end up flooding the engine unless your run higher than 93 octane fuel with a WAYY advanced timing... also with my M52 i cant run 24# unless i get a custom chip or tune for them because its just too much fuel.
also with a mark D chip its designed for the STOCK injectors and not BIGGER injectors and plus the stock injectors are already oversized enough ther 19.5# i believe

on the m42 24LB injectors is about the limit before the car will run bad but if you want to get extra fuel in without having to pay for a tune or raise the fuel pressure its a easy trick. Did I say MARKD chip was for bigger injectors? nope sure didn't and the stock injectors are over sized for a reason.

[///m42 sport]

any improvement in fuel economy?

[Romrog318is]

on the m42 24LB injectors is about the limit before the car will run bad but if you want to get extra fuel in without having to pay for a tune or raise the fuel pressure its a easy trick. Did I say MARKD chip was for bigger injectors? nope sure didn't and the stock injectors are over sized for a reason.

the whole point of this thread was for the MARK-D chip! wtf are your talking about?

and NO not true it runs like complete shit with a stcok chip or a mark D chip with 24# injectors... trust me ive been there this is my second M42 car so i might kno what makes power and what makes power with these motors is BOOST! or a bad ass stroker which will need to be rebuilt A LOT!

why would you put bigger injectors in to only make like 5 HP? and get really shitty gas mileage...

hell my track 318is had 21# injectors with a chip for them and the drive train was completely rebuilt as well as my motor in it and it still didnt run as good as the one i just took out of my 318is...


so please tell me why the stock injectors are over sized??

[bmwconnect]

the whole point of this thread was for the MARK-D chip! wtf are your talking about?

and NO not true it runs like complete shit with a stcok chip or a mark D chip with 24# injectors... trust me ive been there this is my second M42 car so i might kno what makes power and what makes power with these motors is BOOST! or a bad ass stroker which will need to be rebuilt A LOT!

why would you put bigger injectors in to only make like 5 HP? and get really shitty gas mileage...

hell my track 318is had 21# injectors with a chip for them and the drive train was completely rebuilt as well as my motor in it and it still didnt run as good as the one i just took out of my 318is...


so please tell me why the stock injectors are over sized??

I don't trust anything you say because so far you have been wrong about the injectors . I have a e36 m42 running 18psi so I also know what makes power ya goof ball. How do you know the injectors you put in were not 28LB ,30LB, 44LB, an hour? Did you flow test them? did you reference the part number on this site? http://users.erols.com/srweiss/tableifc.htm

The reason why the injectors are bigger then needed is for BMW warrantys back when the car was new. If you run injectors over 80% duty cycle they are prone to failing . Stock injectors run 55% on average thus keeping the injectors in a safe range. this is also why the tunes are conservative from the factory . Its all about the warranty and not having to replace motors and parts . Thanks for coming out

[Romrog318is]

They were 24# and I know because they were out of an S38

And on 18psi how much power r u making?