[mbaker0287]

I've got a 95 GT with some basic bolt ons. I rwant to tune it so I get the best power bossible with what I already have. I've been thinking of the a/f ratio. The MAF, injectors, fuel pressure regulator, and fuel pump are all stock, so I'm pretty sure the setup would run pretty close to a 14.7:1 a/f ratio, or leaner because the engine flows more now. Could I alter the a/f ratio bu adding a fuel pressure regulator or a maf? Also, what is the main advantage of installing an aftermarket maf that is calibrated for the stock 19lb injectors? By he way, I have a cold air, SN95 cobra intake manifold, headers, x pipe wit no cats and flowmasters.

[Kyle F]

The advantage of an Aftermarket MAF calibrated to your injectors is goign to be that it will flow more air. Either it will be larger and smoother, or just smoother creating less restriction to the air flow.

The Mods that you have now are probabl not pulling the car out of the normal compensation ability of the factory programming.

You can adjust the Air fuel ratio of the car by using an adjustable pressure regulator, but this will only work if the computer is outside its correctable range and needs the added pressure to flow more fuel through the injectors. Teh danger here is at a certain pressure level the spray pattern can be pretty erractic and not mix well with the air resulting in a lean condition and loss of power.

If you want to start playing with the Air Fuel Ratio, you need to make sure you get a good wide band set up. Though remember, the 14.1 is not a WOT target, its for normal driving and driveability tuning. WOT is tuned for power and operates off a set table of values know as Power Enrichment Mode (atleast I know this is what GM called it) and does not use the O2 sensor to correct anything. It has to be tuned in, but does use the MAF to compensate fuel and uses a knock sensor to pull timing if you run lean and detonate.