I was wondering if anyone has ran a s4 n/a block on a s4 turbo computer and wiring harness. I came upon a full turbo drivetrain (tranny, drive shaft, diff, cv axles, computer wiring harness etc...) and I am only missing the block, intake manifold and intercooler (I also have the turbo hood, exhaust manifold and turbo).
my plan is to do a large streetport on one of my s4 blocks, install the computer, knock box and atmospheric pressure sensor behind the passenger side fender in a sealed box and run a shortened wiring harness with the emissions wires removed leaving the wires needed for the twin scroll solenoid. I will also use the turbo vane air flow sensor, injectors,fuel pump, turbo fuel pump relay and boost sensor.
Anyways I know i wont have a problem with the wiring but i was wondering how the turbo ecu will handle running the n/a block when it does not see any boost in the hig rpm's? also could this be a more ideal setup for a large street port due to the larger injectors?
thanks for any help. and just to let you know this is going into a completly gutted s4 body to be used during autocross and hillclimbs.

 

id say it would run ok, but if u want max power i wouldnt recomend that.... also for racing i think using a diff ecu and stuff will put u in a diff class for autocross,

but if u want max power id sugest like the rtek 2.0 for NA and then u can tune the ecu to your ported motor and get max power with out a full standalone.

 

thanks kompressorlogic for the reply. I am not sure what class i would be in maybe e-mod or osp2 or somthing. I am mostly curious if there would be any problems and if it would be better overall than a stock n/a computer and injectors.

 

There's no real point to running the turbo ecu and engine harness on an NA block. You will have to rewire all of the connections to the front harness (under and behind dash), and you won't gain anything. The knock sensor is useless, and you're not running boost, so there's basically no chance of detonation. Keep the NA harness and ecu so you have a good base map, or as suggested, a rtek 2.0 NA chipped ecu will be your best bet if you insist on running larger injectors and fuel pump. Really though, streetported NA engines don't need anything more than the stock NA fuel system. You're looking at about ~170 rwhp tops.

 

thanks RotaryRocket88, in this car the entire dash and heater core/vents are going to be removed, the stock harness will be removed and modified so that when I get a turbo block I can install it with no hastle. I know that the knock sensor will be useless but it wont hurt, but my real question is will the turbo ecu be better than the n/a in terms of the increased airflow with the large streetport.
if not I know ive seen a writeup on how the pinouts are different on the turbo versus the n/a and could just swap pins and ecu's untill i get a turbo block.
oh and by the way all of this stuff is free and id like to stay away from a standalone ecu untill i get a turbo.

 

The turbo ecu's fuel map will of course be different from the NA ecu. The turbo ecu is meant to be run with 550cc primaries, so using anything less will lean things out. If the stock 460s are kept, you will definitely run lean at low rpms and likely be lean at high rpms.

If you use the 550cc injectors with the turbo ecu, you will be running rich in the top end. You can use the TII ecu/injectors, but it will be more likely to reduce your car's hp.

If I were you, I would just leave it be until you swap the motor. And even then, keeping the NA harness is far easier than using the TII. The only mandatory change is cutting the knock sensor wire at the ecu because it connects to the power steering switch on an NA. The twin scroll and split air solenoid connections are optional depending on your setup. That's it. 1-3 simple changes.

 

ok so i have one final question how will the turbo vane airflow sensor and boost sensor affect the n/a computer? I ask because I love wiring and plan on setting up the harness anyway and just switching pins, injectors and ecu's and going to the dyno and seeing if their is any difference (if the turbo runs rich I should be safe). then I should post some pic's and dyno sheets, yet it probably wont happen for a few months untill everythings ready.
Thanks for all your help.