Stock ECU turbo

[BMABMW]

Hey guys, I read on the 318ti forum that the 318i stock ecu can handle FI if the boost is less than 9 psi cause it has 2 knock sensors. Can anyone vouch for this?

[nuvolarossa]

what means "can handle"?
It's not that you put the turbo and the ecu will adapt itself with the stock injectors to give more fuel...
you need always at least bigger injectors, a piggyback ECU and a wideband o2 sensor to do a risk free project, but you can do what dasc do with their supercharger kits (knows as DASC): they provide more fueling raising the fuel pressure with a Rising Rate fuel pressure regulator(aka RRFPR) using stock injectors.
It looks like this:
http://www.lextreme.com/pistons/fmu2020.jpg
 
it works but the Air Fuel Ratio is not so good through the revs (lean in a forced induction system -> possilble detonation -> engine damage).
In fact the DASC kit is lean at high revs. With a RRFPR it's a compromise, you set the base pressure with a screw, at atmospheric pressure point.
 
The second adjustment, the needle valve, controls the rate of gain of fuel pressure versus boost pressure.
 
So it will raise pressure like this, when in boost:

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[FONT=Arial, Helvetica, sans-serif]Fuel                 60                     * [/FONT]
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As wrote before, the RRFPR is not the best option because it stress a lot more the fuel pump and all fuel lines, that need to be changed with high-pressure ones.
 
As you see, fitting a turbo in a car that was NA is not a easy route, but you need to know what are you doing. Fueling/ ecu mapping is the key in a turbo system.
In the end you may consider to let a professional ecu tuner to remap your stock ecu, and the results will be better in safety and in power output too.
don't give up:D

[BMABMW]

Excellent thanx for the info, I already got an SMT6. Just waiting on the comm cable and software. I might need help on installation, just determining what wires to tap into...

[nuvolarossa]

great that your doing it the right way!
If you want the SMT6 wiring diagram let me know that maybe I can have something on my hard-disk.. I know for sure that I have the ones for the SMT7 in my backup hard-disk...
 
or simply send a private message to "ludiagsm" here, IIRC he is a reseller and know way better than me about SMT6 and he has a great engine tuned with those piggybacks
Good luck and keep us updated!

[BMABMW]

Definitely! If you've got a wiring diagram for me that'd be sweet! I'm also planning on purchasing a MAP sensor, any suggestions? I was thinking of using a GM 3 bar sensor...

[Rogan]

I have an SMT6, and the micro 3bar MAP..  Once I get my 325e/M42 swap completed and all the bugs sorted, I'll probably be doing the turbo thing..  
I've had many turbo cars, and I'm already getting the itch for the e30 turbo setup..