I checked and compared port timing yesterday between the t2(x) and a 1987 adi 115. A couple of notes. I used a telescoping guage to measure port widths, and this was some of the biggest differences. T2 exhaust port widths are (3 ports) 1.040, .792, and 1.120. 115 was .940, .865, .970. Width of intake ports on t2: .750, .920. width of 115 intake ports 1.118, 1.120 . This does not include the boost port that the 115 has and the t2 doesn't. Port timing on the t2: exhaust opens at 94° atdc, fully open at 151° atdc. Intake upper and lower ports open at 114° atdc, center open at 120° atdc. Fully open at 164° atdc(all ports). 115 port timing: exhaust opens at 97° atdc, fully open at 155° atdc. Intake open at 115° atdc, fully open at 163° atdc. Boost port open at 125°atdc.