15x6" +40mm for all 240sx 15" wheels.
+45
240SX came with 2 different lug patterns. All 1989 to 1994 240sx came with a 4 lug 4x114.3 pattern. While the 1995-1998 240sx SE/LE's came with a 5 lug 5x114.3 pattern. Preferrably you'd want to find a wheel with less than +30 offset for 240SX's.
The 1989 Honda Prelude had 4x100mm offset. The 1989 Nissan 240sx has a 4x114.3mm offset...so, it will not fit.
No. The sentra is front wheel drive, the 240sx is rear wheel drive.
I believe for yours it is 5x114.3. As for the 1989-1996 240sx is a 15x6 wheel with 4x114.3 or as for the 1995-1696 240sx se is a 16x5.5 wheel with a 5x114.3. Reference: http://www.discountedwheelwarehouse.com/Nissan___Vehicle_Bolt_Pattern_Reference.cfm
The wheel spacing itself will correct, or increase, the offset and properly push the wheel out. The spacers can also be change out to provide a better spacing and offset.
Yes the 240sx Is back wheel drive, but its called RWD or rear wheel drive. Meaning the rear tires move the veheical
Yes
34-45 offset
Is the estimated tuck in or out from the center of the wheel, example: (nissan sentra) 18x7.5 +40 offset is tucking in 40 mm from the center of the wheel or (old chevy pickup) 15x7.0 -10 offset is sticking out 10 mm from the center of the wheel.
Rear wheel drive
The stock wheel has a 55 mm positive offset. Positive offset means that the wheel is tucked into the fender well 55mm more than it would be if the bolt flange of the wheel were perfectly centered in the wheel. Negative offset means that the wheel will stick out of the fender well more. So........ If you reduce (55mm-45mm) the positive offset my 10mm, your wheels and tires will stick out of your fenderwells 10mm further than the stock wheel, assuming that the aftermarket wheel is the same width as the stock wheel.