I have a very knowledgable friend willing to try things with my car. His idea was to do a "fuel cut defender" (He is an electrical engineer and tuning geek) and a manual boost controller, and then use the Delta to tune it slightly. does this sound reasonable? Anything to be aware of? This wont be for awhile. thanks Will
I know I should let Matt offer some input here, but that doesn't sound like a very elegant plan to me. For starters, your injectors aren't much bigger than regular old WRX injectors, so you probably don't have a lot of headroom there (although I'm not sure what stock IDC's are like exactly). It sounds like he wants to blindly turn up the wick. What exactly is the purpose of this plan? More horsepower? I'd get an exhaust before I'd go slapping on some mysterious sounding FCD and an MBC.
"very knowledgable friend" doesn't sound like he has Subi experience FCD is to trick the ECU into thinking it has less boost than it does. MBC is to add more boost. Delta Dash I assume? Is he a liscensed user? Ok the problems I see here are: 1) the STI runs at the high 90's for IDC's if you add more boost you need more fuel. You are not going to get more fuel from the stockers. 2) with the aditional boost you need to change the timing. Sorry this is just a bad idea! What do you want from the car? lets get your goals and then we will point you in the proper direction.
he has no subie experience. but he is actually a VERY knowledgeable person when it comes to any turbo car. he has tuned the fastest S4's in the nation if that even means anything. i know its not a subie or an sti rather. he and i were just curious. i would be purchase the deltadash. this isnt a set in stone thing. just curious if this would even work. i would like to just tune the car up a tad. nothing extreme. just some more hp and some more speed. same as a moderate tuned ecu would do. as a side note, i know that an audi isnt a subaru and that every turbo car isnt the same. he was wondering some of these things and so was i. he has been told by some of the biggest audi tuners that his ideas wont work, yet he still produces the fastest s4's with his kit. if this is a poor idea i guess i might have to go the mainstream route.
Well like Matt said, there just isn't much room to turn up the boost and the turbo wouldn't run much more anyway. Unless you want your injectors just sitting there wide open at 100%. Call me crazy but FCD's sound like real hatchet-job "tuning" devices. I would also carefully investigate the amount of tuning the Deltadash actually lets you do.
First off, the subaru motors run ALOT richer than most turbo cars. The subies like that 10.6-10.8 through peak tq, and taper off from there. I would guess that as soon as you tell him that, either he will understand that these motors like gas, or call me a liar and I don't know what I am doing. If I was you, I would skip all the other little things and just pick up a utec. If nothing else, it will give you a steady timing curve, which will make the car seem just as powerfull every run. Russ
First Delta Dash only allows global changes to the fuel, timing, or boost. This would not be the best posible way to tune the car. You would want to make changes to indivudual load sites to make changes based on the AFR, Timing, or boost requirements. If you tell this to your Audi guy he will understand completely. Like Russ and Joel have said this plan you are thinking of is not the best. If I were looking for a mild upgrade in power I would do the following: TBE: either Turboxs stealth if you want quiet Turboxs full TBE Invidia full TBE This will free the exhaust flow to make the turbo spool faster. Modify Your stock injectors to flow 810cc (Perrin is the company) EM: either a UTEC (turboxs)most widely used and suported or a new comer the HYDRA (element tuning) Personally I would use the UTEC since the Hydra is new to the market and yet to be proven totally in my mind. Now EM is only effective as the data you can get from it or the car. To tune the car properly you will need a wide band O2 sensor to get the AFR's from the car. Both the Hydra and Utec have WB that are intergrated into the logging abilities of the EM. This is really a must since you are flying blind without it. Finally you will need to control boost better once you run a TBE w/o a cat. You will get what is called boost creep, the EM in the car does not have the ability to finely control the wastegate enough to stop over shooting the tardet level. Solution: Port the wastegate on the turbo and upgrade to the GMC syclone seliniod. This is what Russ and I use to give us better control of the target level. Ideally I would recomend just upgrading the turbo to something else since the VF series are pritty well maxed out on the STI. But that is a different topic. So it starts to add up quick TBE: 1000.00 +/- depending in brand modified injectors: 250.00 EM: utec:1000.00 tuna (wideband): 500.00 GMC part: 20.00 porting: I charge 75.00 Matt
Thanks guys. It is now making alot more sense. I was just seeing what was possible. Sorry if I was seeming a tad n00bish. But, I am...
Better to ask than to blindly buy parts. This way you get the right stuff and you dont grenade your motor. Matt
