1993 4.0L Running Rich

[Legospud]

I have a 1993 yj stroked 4.0 liter 9.5 to 1 compression, cam nothing to radical, I think its a 254 with 115 lobe, 25 lbs injectors, The head is original just polished, original intake and throttle body and a new stainless steel header. I have finally got it to run really good, except very sluggish at low rpm's, high rpm's runs awesome very powerful. but I can tell that its running really rich and I have fouled a couple plugs in the last week. I have had suggests that I need to bring the fuel pressure down, so I need an adjustable fuel regulator, or I need a 2000 or newer intake to bring the air up. Anybody else had this problem, I need to get it right!
Thanks Chris

[Cheromaniac]

A MAP adjuster would also work for you.

http://www.angelfire.com/my/fan/MAP_adjuster.html

[Muad'Dib]

I have a 1993 yj stroked 4.0 liter 9.5 to 1 compression, cam nothing to radical, I think its a 254 with 115 lobe, 25 lbs injectors, The head is original just polished, original intake and throttle body and a new stainless steel header. I have finally got it to run really good, except very sluggish at low rpm's, high rpm's runs awesome very powerful. but I can tell that its running really rich and I have fouled a couple plugs in the last week. I have had suggests that I need to bring the fuel pressure down, so I need an adjustable fuel regulator, or I need a 2000 or newer intake to bring the air up. Anybody else had this problem, I need to get it right!
Thanks Chris

Do you happen to know what your STFT value is? This may give you insight into which direction you need to take.

Large Fuel decrease = Replace Injectors
Smaller Fuel Decrease = FPR
Fine Fuel Decrease adjustments = Map Adjuster

Personally with my 4.7L im running smaller injectors than most. If your running 25# Injectors on a non-stroker, then your running larger than most here with strokers. Most run 24#. I am running 19# (with the pressure up slightly) to make then flow at 19.2#hr.