I an the original owner of a 1988 4 cyl. Fiero, 180,000 miles. I had Tach problems - it reported "double" RPMs and the neddle would touch the oil pressure needle. I had to remove the "pointer" head to prevent damage to oil pressure needle. Sounds ...
The 3.4 DOHC is almost exactly the same as the push rod, though I did notice that it has more HP and TQ. I would rather only put one of those engines up, and I put up the OHV, let me know if I really should put up both or if I should change the one I have to the DOHC.