My friend has an '89 STD and we're adding the DX exhaust manifold, cam and ECU. We're hoping this will bring the power up to the 92 hp of the DX. I doubt the 4-speed has a direct drive 4th gear. That's usually only true for RWD transmissions. It's probably about the same overall gearing in 4th as the 5-speed in 5th. Anybody have a factory/Helms manual for the ratios?