Fuel Pressure
 

I have an adjustable fuel pressure regulator w/gauge, and an A/F ratio gauge in my 98 cobra. It was in the car when i bought it. My question is is it possible i have bigger injectors too? or would those upgrades just be for the cold air intake and exhaust mods on the car?

larger injectors aren't needed unless your supercharged or spraying a large shot of nitrous....they won't do anything for a mildly modded car. Who knows what the car had done to it before you bought it. A lot of people have guages because they "look cool" rather than actually needing them.

Here is an easy way to tell what injectors you have, just tell us the color and we can tell you if there stock or not.

By adjusting the fuel prussure you can make the injectors work like bigger ones to a point. 24lbs at 33psi would be like 26lbs at 39psi,or something like that. I turned up the pressure on my old GT to 40psi and it went rich,had to back it down.I still have my regulator but haven't put it on the cobra.

Mine was set too high and I got Rich on Bank 1 and 2.

on the gauge the highest it has gotten to is 36psi but it usually runs around 30

Is that with vac line on or off?

im assuming its on.......its under normal driving condtions

The Base PSI is set when at idle and unhooking the vac line, let me see what our 4v should be set at but in the meantime here is a good read http://www.accufabracing.com/article%202.htm#FPR

at idle its about 25-26, when driving its at 30 and when driving hard it jumps up to 35-36

Heres what the Ford Manual has see pic. I will ask Randy to see if here can double check for us.

Yours is low heres what Randy says https://mustangboards.com/the-parts-...d=1#post257426

well i dont know all that much about themso how would you adjust it? it looks like the vac line is on............and the injectors are light blue and i managed to get a number......F55E-A2E....and i just looked it up.........seem to be stk 24lb injectors

The way you set the FPR ; while car is on remove the Vac line that is attached to it. Either cap the vac line or hold it shut with you thumb. You then turn the adjustment screw clockwise to raise or counterclockwise to lower pressure. You may need to use an allen key. Adjust it 38-40psi then reconnect the vac line.

so will my car run better? is that why it hesitates when you mash the gas?

That may be the problem as you dont want to mess with the stock setting unless you have a need to. If you get your car tunned the person tuning it will be the one messing with it but you are mostly stock with a few bolt ons no reason to increase fuel pressure.