Studdering under load

I have a 1989 5.0 mustang and when i step on the gas the car wants to studder. The car is blown with lot's of mods. Ported heads, throttle body, mass air, 30 pound injectors, 190l pump, and so on. We have ruled out a fuel problem. Someone please help.  

I’ll give you my opinion, but you did give much background.  For example, have you just performed an upgrade or did it just start to happen?fficeffice" />>>

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When I had similar issue, it was due to some sort of vacuum leak.  The MAF sensor was not sensing any air and idle, so the car did not respond well.  But, while driving, the MAF sensor was sensing enough air volume to make the computer behave correctly.  >>

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Another instance, my MAF sensor went south.  I installed a new MAF sensor and the car ran like a champ.  I guess those things are more delicate than I originally thought.>>

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In your case, I would use a Propane Leak Detector to see if you have a vacuum lead.  What you do is attach a propane tank to this wand looking apparatus.   While the car is running at idle, this is the best time since the intake is under the most vacuum, you slowly move the wand around your intake track, listening for the engine to suddenly pick up on RPM.  If so, you found your leak.>>

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Good luck,

I actually found out the problem, i replaced the spark plugs, and spark plug wires and it runs great. But now my oil pressure gauge fluctuates.

When my car idles it goes up and down, up and down, but when i am driving it jumps right to 50psi and stays there no matter how much gas i give it. ANy one have any suggestions.

Might be time to check all your bearings. The pressure going up and down is normal with a pretty big cam. my car does the same thing.