I recently bought a '94 300zx 2+2 non-turbo from my grandmother that had been sitting for about 1 1/2 - 2 years to be fixed. After having a head job done I bought it and drove it less than a week beore breaking down and having a mechanic estimating over $7 grand in repairs to fix the existing motor. He said because it sat so long it had surface rust on the bearings causing it the motor to go completely bad and about to lock up. I turned here for help finding a good replacement engine to put into it. I called around and got a suggestion to find a U.S. Spec motor rather than JDM if possible because JDM's tend to have oil problems? Is this true and are JDM motors good because then seem to sell for pretty cheap.. Also, is it JDM or US Spec that comes stock in the car? Also, i read things about OEM engines in that car? This is all new to me and is an ameteur on cars so a little help would be highly appreciated. Thanks