Oil pressure fluctuations under hard acceleration?

[Soma07]

Car: 93 Trans Am, 350ci LT1, 6 speed manual
Oil: M1 SS 10w30

Under hard acceleration (WOT in either 1st or 2nd) the oil pressure in my car will drop from ~60psi down to about 45 until I let off. Not terribly low but I don't think its right either.

The strange thing is I can rev the car in neutral and the oil pressure is steady at ~60psi. I can also lift of the gas a little (80% instead of 100) and the pressure will go back up too.

The car has ~190k on it now and I'm not sure when it started (I bought it almost 4yrs ago with 118k).

Any ideas? It seems hard acceleration is the key. I was thinking either the pickup has completely fallen off the pump (thus uncovering it under high G's) or the oil is getting pushed to the back of the pan and the crank is whipping it into a foam?

Thanks!
Jason

 

[sbc350gearhead]

If the pickup fell off..........you would know it.........trust me.

 

[Soma07]

quote:

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Originally posted by sbc350gearhead:
If the pickup fell off..........you would know it.........trust me.

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Thanks, I knew it was a longshot but I figured I'd throw it out anyways.

 

[JohnBrowning]

If oil pressure drops as RPM's rise then it is usualy rod bearings.It would be even more pronounced under hard lateral acceleration. THe rod bearing hemorage more at high rpms and as lateral loading increases this is multiplied even more!

 

[TheLoneRanger]

It might also be worn main crank bearings, especially the rear one that contains the thrust bearing surface. If this is the case, the rear main seal will usually leak. Chances are that both rod and main bearings are worn......

 

[Schmoe]

How about the location of the oil pressure send unit?