TXMach

Actually, when people are doing extensive dyno tuning, it's typically not done on a handheld. It's done via tuning specific software on a laptop. When it is done on a handheld, it's because someone who knows what they are doing can push the envelope a bit further with the AFRs using the dyno and a wideband. The "canned" tunes don't push the envelope quite as far because the companies that sell them don't want to blow people's engines. They sell you a good quality, yet safe tune.

As I mentioned before, I'm completely satisfied with the tunes I got from Bama. I'm sure there are some cases in which issues may arise, or no improvements are noticed, but in my case, they work pretty well in fact. I'm certain that for the situation at hand, a "canned" tune is well more than enough to correct his issues, as well as make some overall engine performance improvements.

JeffBall

Im not really looking to pull any more performance out of this car...This car has more than enough power than what i need. (Supposedly 407 hp from the factory, after roush did their stuff, however some guy did dyno his and got 360 or something like that). My main thing is getting these o2 sensors fixed(Which should hopefully increase my gas mileage a tid bit) and the speedometer issue. Im fairly certain the car is running SUPER rich. Can't say for sure, just smells a little rich to me. (Could be due to the lack of cats). I plan on eventually throwing high flow cats back on it, due to Virginia state inspections.

TXMach

Gotcha. The 407hp from the factory is flywheel hp. The 360 someone else got is wheel hp. An engine makes so much, then loses a bit as the power transitions to the wheels. Typically about 20% is a good rule of thumb.

Good luck fixing those issues. In my opinion for something that will be driven on the street and inspected by the state, you'd be best off with cats. I'm certain that from what you describe, your car is running super rich. The O2s aren't necessarily in need of replacement though. They are probably doing their job just fine, however the long tube headers have changed exhaust flow so dramatically that the signal they send just isn't working with the Roush AFR tuning. I don't know if I mentioned before, but with long tube headers, an application specific tune is not an option. It is absolutely necessary.

As for your spedometer issue, the previous owner likely changed the gears in the rear end. A tune also corrects this. But first you need to find out what gears you have.

Aaron Bridges

With the car you have I wouldn't put a basic handheld on it I would get it Tuned At a Dyno Shop. If you could make the run up to SC Pro Dyno In Ft. Mill is the best in the South East They guy is a guru with Ford Performance. And with you car being one of the rarest around I would be iffy about putting cheap **** on it. Im super jealous. but it sounds like you just need an A/F adjustment due to the Long tubes. your car has a lot more airflow going out than it ever did from the factory. a tune should take care of your problem. be ready to drop about 750. for the tune and a proper hand held tuner. some places like Pro Dyno where I had mine tuned can put an X Cal chip . cheaper than a handheld but does the same job just doesn't have all the gizmos and gadgets that a handheld does. but also 175$ cheaper

JeffBall

I replaced my O2 sensors with NTK's and the codes are gone. So maybe the sensors i had were just starting to go bad. I purchased a bluetooth OBDII sensor and use the Torque app with my Android. Shows me getting good voltages from my o2 Sensors, ranging between .1volt and .9volts. As for the cat issue, Im stationed down in Florida, and Florida doesn't have state inspections (Also the car is registered in VA, however i wont be going back to VA anytime soon so not that big of a deal) I spoke with HP by Hermann(read over on SVT forums that this guy is a guru when it comes to tuning. He quoted me right around $500 with a handheld tuner and a custom tune. Im quite happy with this car...has more power than i need. The car has 3.73's in the rear. I actually shut up a guy in a porsche carrerra last night from a stop light. Im absolutely in love with this car....only thing i don't enjoy about it is this heavy *** clutch. My left leg hates me. World of difference from my 01 v6.