KA-T is the stock KA engine (KA24E 89-89, and KA24DE w/ hot cams 91-94, and S14 KA24DE 95-98) and adding a turbo to it. i.e. KA24E-T and KA24DE-T. Cheaper and put out way more hp than an SR (fastest I know of is 633whp on KA-T.org)
As for the conversion .. The car will eventually look like this but with a different body kit...