If you don't want the fastback models then that leaves you with the S14 chassis.
The 95-96 are commonly called Zenki, the 97-98 Kouki. Note the different headlights
Zenkihttp://
www.belivamg.com/cars/95_240SX_1.jpg
Koukihttp://monkeyads.com/proofs/_24252_28710.jpg
The s15 was never produced in the United States. It's often called a Strawberry (again b/c of the headlights)
http://www.j-garage.com/nissan/silvia/silvia.html
You've got several motor options: Turboing the KA24DE in the car, Swapping in a SR20 motor (the motor the 240/sylvia had in Japan -- it's already turboed) or some variation of the Skyline Motors RB20, RB25 or RB26.
There are pros and cons to each of the choices. Cost, power, etc..
The KA-T forums should be able to help the KA24DE.The SR forums should be able to help with the SR20.The RB forums should be able to help with the RB/Skyline Motors.
All S14 Models came in either a base model or as an SE model. A way to tell is the SE trim cars came with 5-lug wheels. Another plus to the SE is that some came with VLSD (both wheels spin) with or without ABS.
In short, there's not much difference in the S14s. Just a few more bells and whistles depending on the trim of the care (base or SE).
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