Well, it was all totally new to me (the 3.9 engine that is). First of all, i have access to both the new OTC Genisys scan tool, and the Ford Rotunda tool (aka the "dealer computer"). The OTC scan tool allows me to read information from every sensor in the car, monitor frequencies, voltages, ect. and at the same time graph, and record real time runs. And, as i said, i also have installed a larger MAF sensor, and the MAF tuner program (which allows me to adjust air/fuel in 40rpm increments relevant to Throttle position). If you would like more info on the MAFterburner, go to
www.mafterburner.com BUT!, i strongly urge those of you with little knowledge of the 3.9 NOT to use this device! It can cause severe damage that will NOT be covered by warranty. (Note all runs were done with sunoco 94 octane)
Now, with the tuning issue. I was aware of the 10.5:1 compression, and was sure to start out with very LOW boost (3lbs). I started by making low RPM test runs, with a friend in the passenger seat monitoring Air/Fuel, Timing advance, and most importantly the engines two knock sensors. I adjusted the air/fuel accordingly (went on the rich side for safe measures) and increased boost to 5lbs. This time (making the same part throttle run) I paid close attention to the cylinder head temp sensor as well. After getting the proper air/fuel, and making sure temperatures were not exceding the stock base line readings, i took the car out on the expressway. The results were amazing at 5lbs. Unfortunately i never got a G-tech (or similar device) in the vehicle durring runs. But cruising at 60, then punching the gas would rocket you to 80mph in no time, sending your head to the seat rest. Impressed with the results, my friend and i decided to go and get his 2003 Acura RSX Type-S. We had always done little things to our engines (polish throttle, bypass throttle preheat, intake, exhaust, ect) and i knew where i stood head to head with his car. Before the turbo, i would stick with him right up to 60, then he would gradually pull on me until i was a good 5 car lengths behind him. When we went on my first "turbo run" i would choke slightly upon launch (mass air problem), But as soon as 3200RPM hit in 1st, i pulled right next to him, passed him, and watched him in my rearview. We were both totally shocked.
The exhaust sounded awesome coming straight from the turbine. The sound it made spooling up, and the woosh of air from the blow off valve when i would quickly let off the throttle was such a rewarding sound. And you can only imagine the looks i recieved from the kids on the road next to me driving thier civics and neons as i would drive by in an inconspicuous lincoln ls, and let my blow off valve make its distingtive "cracking whip" sound. It was a real head turner.
Now my next step was to do away with the choking during a hard launch. I found that the problem was with the low rpm mass air voltage durring open loop (full throttle). I spent at least an hour on this, and improved it, but really never got it perfect. By now, the only DTC activated was "MAF inconsistant with TPS" which from what i have gathered was due to the MAF frequencie being so off on low rpm. After fixing the graph on the mafterburner program, i cleared the dtc and never saw it again.
The final boost lever i was at before removing the turbo was 7lbs. I had absolutely no problem with over temp, lean conditions, knock, or any other out of perimeter problems. But i was not willing to go any higher than 7psi.
On the e-way one night while doing a test run, i heard a noise that like i had blown a hole in the exhaust manifold. I got off on the nearest exit, pulled over, and popped the hood. Hearing the noise come from the center-lower-rear of the engine, i knew right away it was an egr problem. I drove home taking side streats, and dug into it. It was surprised to see that i had blown the downstream hose on the egr pressure transducer. The hose is reinforced with nylon string! But, after further inspection i noticed the silicone hose had actually started to dry rot from age, and decided to just replace both hoses. Very next morning i orded both hoses from kistler ford in toledo, recieved them that day, and installed both. The hose apparently blew from a combination of ehaust restrictions from the turbine under full load, and the 7psi of boost coming into the intake manifold, and pressurizing the egr valve in the opposite direction. After replacing the hoses, i never had another problem. future plans are to regulate the egr to close after around 3psi of intake boost to prevent this from happening again, while at the same time keeping egr functions the same at lower boost, and crusing rpm. This was the only major engine problem i had encountered.
Shorlty after, like i stated before, i fryed my bearings driving like an idiot, and need to rebuild the turbo. I am planning on devising a way to put the turbo in the engine compartment (around where the stock air box was) and also running a small intercooler. This is turning out to be VERY difficult with such a lack of room. Being that it is summer and i want to be able to drive the car, i am building everything piece by piece until it is ready to be bolted up. I realy have no estimated done time at this point. But i will be sure to post completed pictures and results when i am done. And hopefully this time i can get on a chassis dyno at a shop down the street and get some real tuning in.
Well, im sorry for the long post, but i tryed to touch all bases. If anyone has any other questions, feel free to ask (but dont expect a reply till after 2am my time lol, im a night person)
