88 Fiero's are popular because of the suspension and brakes, But repair/upgrade cost's of these areas on the 88's is slightly higher due to the differences and low production numbers. 85 thru 87 fiero's are very interchangable. 84 Fiero's had some differences in harness routing which makes swapping to a V-6 a little more difficult than the later years.
As for trans,
84 4spd had 4.11 gearing. 85-86 V-6's had same trans with different gearing.
85-88 4cyl had Izusu 5spd
late 86 thru 88 V-6's had Getreg 5-spd
all automatics are the same. (some difference in gear ratio's do exsist)
All the above transmissions have been used with V-8's. Over 300hp with automatic's requires some heavy duty parts to be installed but all others have worked well.
Differences in body styles are:
84-88 coupe same body style, different nose and bumper on 87 and 88.
84 and 85 SE same body style as coupe, 85 SE had optional V-6.
84 Indy, 85 GT, 86/87 SE all had same body style, areo nose, ground effects, 85GT came with a V-6, 86/87 SE had standard 4 cyl with optional V-6.
86-88 GT had fastback body style, V-6, 15 wheels.
88 Formula coupe body with all the mechanical upgrades of a GT. (V-6,WS6 suspension 15" wheels,etc)
Welcome to the forum!
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