Possible Engine swap???
Mercenary41688
05-11-2009, 03:30 PM
Need ta know if the is a tranny adaptor to keep my 5 sp. trans with a 3100 motor or if it will bolt up.:confused::banghead:
MrPbody
05-12-2009, 02:08 PM
Merc,
What engine is in there now? I ask because either the 2.5 4-cyl. OR the 2.8 V6 WILL "bolt up" to the bell housing flange.
Depending on what year yours is, the flywheel may or may not work. 3.1 (3100) has the same hub on the crankshaft as both 2.5 and 2.8. 2.5s and '88 2.8s are "internally balanced", where pre-'88 2.8s are not. If you're putting the 3.1 into a pre-'88 V6 car, you'll need another flywheel.
If your 3.1 has aluminum heads, you're in for a real adventure getting it to "fit". The water pump system is completely different, and will require a modification to allow it to "clear" the passenger's side shock tower. It's been "done", to remove the timing cover, slice it in "half" (top and bottom), cut the same portion from the iron-head timing cover and use the water pump system already IN the Fiero. It's not a job for a beginner... You'll need some fabrication experience and some "welding aluminum" experience. You will also find, with aluminum heads, your exhaust won't fit, either.
Not all is "lost". There are SOME performance benefits from using the aluminum heads. Better flow and more efficient chamber are the main "points". Howeveer, the iron heads from the 2.8 will bolt right oin the 3.1 and deliver decent performance. Some judicious port work and larger valves can turn the little V6 into a hot rod!
Jim
What engine is in there now? I ask because either the 2.5 4-cyl. OR the 2.8 V6 WILL "bolt up" to the bell housing flange.
Depending on what year yours is, the flywheel may or may not work. 3.1 (3100) has the same hub on the crankshaft as both 2.5 and 2.8. 2.5s and '88 2.8s are "internally balanced", where pre-'88 2.8s are not. If you're putting the 3.1 into a pre-'88 V6 car, you'll need another flywheel.
If your 3.1 has aluminum heads, you're in for a real adventure getting it to "fit". The water pump system is completely different, and will require a modification to allow it to "clear" the passenger's side shock tower. It's been "done", to remove the timing cover, slice it in "half" (top and bottom), cut the same portion from the iron-head timing cover and use the water pump system already IN the Fiero. It's not a job for a beginner... You'll need some fabrication experience and some "welding aluminum" experience. You will also find, with aluminum heads, your exhaust won't fit, either.
Not all is "lost". There are SOME performance benefits from using the aluminum heads. Better flow and more efficient chamber are the main "points". Howeveer, the iron heads from the 2.8 will bolt right oin the 3.1 and deliver decent performance. Some judicious port work and larger valves can turn the little V6 into a hot rod!
Jim
Mercenary41688
05-12-2009, 03:08 PM
It currently has an 85 duke with the 5 speed manual trans. it WILL bolt up??? Also what is involed with mounting it to the cradle???
MrPbody
05-14-2009, 08:20 AM
To the best of my knowledge, yes, the bellhousing flange is the same.
I don't know for sure about the cradle. It may be prudent to call a wrecking yard with an interchange manual and see what they say.
Jim
I don't know for sure about the cradle. It may be prudent to call a wrecking yard with an interchange manual and see what they say.
Jim
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