Differences in Engines: 89-95 3.8 Taurus vs. 89-97 3.8 Thunderbird
Block and Internal Differences:
- The Taurus' transmission bolt pattern on the block is different to accomodate for the FWD transmission
- FWD 3.8L models have a balance shaft, the RWD models do not. Ford decided to omit the balance shaft and instead put huge, rubbery, fluid filled motor mounts on the RWD models. Because of this, there are minor differences in the cam setup, and major differences in the block. (Openings not bored, oil passages slightly different.)
- the RWD cam has a spacer instead of a balancer drive gear. Also the RWD balancer bores are unfinished. The only RWD 3.8L that came with a balance shaft was the 1988 Thunderbird/Cougar.
- The Taurus' upper intake from plenum to throttle body bore measures 14.5". The Thunderbird's measures 15.25". Whcih means there is a difference of 3/4". This was due to transverse mounting of the engine in the FWD Taurus. The upper intake of a Thunderbird is too big to fit under a Taurus' hood.
- The Taurus upper intake plenum has a larger throttle body bore.
- 96-97 3.8 Thunderbirds have a coolant bypass built into the upper plenum beneath the throttle body passage. 89-95 do not.
- 96-98 mustangs and 96-97 thunderbird intakes have smaller 6mm bolt holes than the 89-95 taurus, thunderbird, and 94-95 mustang which are 8mm
Anyone feel free to post anything more they may know about this subject