i have a 347 stroker with all the bells and whistles in my gt. Its still fuel efi and is n/a. I heard that if I have it tuned buy a shop and have a chip put in it that I wont need o2 sensors anymore. Is this true? If thats the case do i need to to still be running a egr valve?
They could tune the EFI without the O2 sensors, but it doesn't make a bit of sense to do so. Any tuner who would recommend tuning that way, you should run like hell from and find someone competitent. If you tune without your O2 sensors, you lose the adaptive strategy that's built into the EEC, and it has no way of compensating for any changes in your air/fuel ratio.
okay so ill tune with the sensors in but does anyone recomend stock o2 sensors or should i fork out the money for a wide band. Is it that important to have to watch the ratio or if its tuned would the ration stay the same. remember there is no power adder.
Eh, I'd get the wideband if I was tuning it myself, but it's not necessary if you're getting a tune. Stock replacements should be good.
I just realized that I didn't answer part of your first question before, too. You can have them disable the EGR in the tune, and eliminate it if you'd like to.
Well i would like to add a couple things here. Tuning a car without the O2 sensors is essentially forcing full time open loop. This means that the car is ignoring the input from the narrow band O2's. This type of tuning is often done on non-street car applications or on applications when people desire the maximum fuel efficiency.
I agree that the adaptive control is a good feature...but sometimes it can fight you. Adaptive will always strive for a stoich mixture...and if you want something safer (richer) or more fuel efficient (leaner)...the adaptive logic can get in the way. I know some people tuning in OL with great success.
With all that being said...i think you should just put some nice new stock narrow band O2's in there and get a custom chip burnt. This will be the cheapest, quickest, and easiest option. Buying a wideband is practically seless if you have no way of tuning the car. They will have a WB at the dyno when they tune it...so the A/F ratio should be dialed in when they tune it. good luck man.
FWIW, I wouldn't bother taking it to a dyno to have a chip burned - tried that and pretty much just flushed a few hundred bucks down the toilet. If I were you I'd either look at getting a PMS or a Tweecer (although given your comment about needing the O2s or not, the PMS might be a better choice) and get a wideband. That way you can tune the car yourself.
You will probably spend close to $800-$1000 to get a chip tuned by the time you have paid for the chip and the dyno time. I think chips are around $250-$300 for an SCT chip. The dyno time will likely be around $400-$500 but that could vary.
A used PMS and wideband will be around that as well and you can tune it to your hearts content.
You can use a Tweecer instead and save a few bucks, but it's time consuming and complicated to learn how to use.
Go to www.stangtuning.com and start reading.