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Tuning Link G4+ Closed loop lambda on a 13b turbo


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Hey guys ive purchased a link g4+ extreme ecu for my rx3 , swapping from a microtech lt10c

have a few questions please

can a bridgeport 13b turbo be tuned using closed loop lambda up to 22-24psi using the link wideband can?

What advantages and disadvantages does open loop vs closed loop have on this type of setup? 

does anyone have dead time info for indy blue/white 1680cc injectors?

thanks in advance 

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I would suggest always having the "Open Loop Lambda" table turned on.  What this does is factors the lambda target into the fuel calculation.  So, if you turn the fuel table so that the measured lambda matches what is in the target table, then later if you want to try any changes to fuel mixture in future (say for instance you want to try leaning it off a bit in the cruise area) then you just need to change the target and the actual lambda will follow - you dont need to retune the fuel table everytime you want to adjust the mixture.  

As for Closed loop - it is not designed for tuning and would generally be off when you are tuning as it will often work against any changes you make.  Typically closed loop is enabled after tuning to compensate for small errors due to changes in environmental conditions etc.  


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Thanks Adam for your quick reply!

so to conclude, Get the tune as spot on in all areas as best i can on the street and switch over to closed loop match the target afr to match what ive tuned to then if i travel to taupo which often we do the CLL will take care if the altitude changes which have plagued me in recent times?

Adam you don’t happen to hve any injector data on the old indy injectora do you?

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Yeah that would be the basic idea.  How well you can tune it on the street will depend on how much time you have.  Its a whole lot easier on a dyno when you can hold it at a specific RPM and load while tuning.  Yes CLL will take care of changes like that, although I suspect your problems were probably more due to the very basic microtech, that doesnt even have baro compensation and probably the injectors too.  

As for the Indy blues they are horrible injectors.  I think everyone gave up using them in about 1995.  Especially as primaries they are nasty as anything below about 2ms pulsewidth they are completely erratic.  Our FD test car actually has them as secondaries and they arent too bad for that as you can program them not to work below 2ms.  It might be a good idea to find something else for your primaries.

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Great info adam , does the baro sensor compensate automatically or is that another table ill need to work with?

sorry i should have said the indys are secondarys

Bosch ev14 1000s in primarys

Do you know if my pre existing wideband will work along sode the Extreme? Or will i need to buy thr Link version to use CLL?


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Ok those injectors should work fine for secondaries.  I have attached a pic of the secondary deadtime table from our FD which has indy blues.  I have no idea how realistic they are but it works and unless you have no alternator then deadtimes are generally not so critical for secondaries.  

All Link ecu's have a baro sensor on board.  For a turbo car if you use MGP on the fuel table Y axis that will give you pretty good baro compensation automatically.  

Yes that CAN lambda should be fine.  I just looked at their documentation and it gives the CAN ID's hich is a good start but it is missing a critical piece of info - that is how the data is scaled and what bytes it uses.  However I can help you work that out with a couple of tests if they wont give you that info.  So connect the Lambda CAN H/L wires to the Link CAN H/L wires.  Worst case you will have to send the box to me in Auckland to sniff the CAN.



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