.I'm looking for an opnion..I'm trying to build up a mild street engine..I've been reading and people have been talking to me about the different ways to build up an L28..what I have is two good motors one is a F42 block with an N42 head (round ports) and the other is F54 with a P90 squire ports..some are telling me to change the head on the F54 and put on the N42 and so on and so on...you get the picture....I had plans in bore out the F54 block and cleaning up the P90 head...leaving eveything stock inside, except the size of the piston itself.....any ideas on this would be great...and the other quick question..how do you tell the difference between a Turbo 280zx rear end from a Non-turbo. I'm in the understanding one is 3.54 and the other 3.91. With them siting side by side it hard to tell..is there a casting or stamp number, I can be looking for?

 

I wouldnt bother boring out the block i would just grind the cam in it, is it efi or carb motor ? if its carb get a good set of SU's or if its EFI get a good aftermarket computer for it.