hey

i was wondering if a gs-t turbo back would bolt on to my 98 eclipse rs

Uhhhhh.....what is a "turbo back"?

sounds liek a straight pipe.... no it won't bolt up engines lay out differently

exhaust maybe?

i think he is talking about exhaust, and no it wouldnt work

The turboback wouldnt work, and I'm not sure the catback would work. But the muffler only replacements (with the short curved pipe that goes over the rear axle) are interchangeable between GST and NT. In fact, a somewhat common upgrade for NTs is a stock GST muffler ;)