Having problems with your 1985 Pontiac Fiero ?

Not Sure What Engine to Replace Iron Duke in Fiero

\015 \015\012Hello I need some advice on what my options are for replacing a knocking 2.5 L (VIN code: R) in a 1985 Fiero Sport. It has the 5-speed transmission. This will be a daily driver. I enjoy driving the car, except for nearly getting run over due to poor acceleration.\015\012 \015\012Reliability and fuel economy are still important to me so I would was thinking of sticking with a 4 cyl, but as long as I\342\200\231m going to the trouble of replacing the engine, I would like to get better acceleration/performance, if I can afford it. (I also plan to upgrade the breaks and suspension eventually.) I\342\200\231m not going to be street racing or anything, I just want to be able to keep up with most cars on the road.\015\012 \015\012One concern I have is with putting back another Iron Duke\342\200\246I like the idea of getting something more modern and efficient and even slightly lighter, but I suspect it would cost more and require a different cradle, wiring, ECM, and maybe a different transmission. Is there a more modern 4-cyl that would bolt directly in that would be better? Or would an Iron Duke that been rebuilt with better rods, maybe a performance crank/cam, etc be a good idea? I'm open to upgrading to a 6 cyl, but I want decent fuel economy.\015\012 \015\012I\342\200\231d like to know what the best options are and generally the pros and cons of each. Thanks.\015 Posted / edited by AnonymousUser on : 08-08-2022

Answers :

I don't know if you listened to the insane person who previously answered but in a fiero w/o any mods you can bolt in a 3.4 V6 (1992-1995 Camaro/Firebird) or a 4.9 Cadillac V8, four cylinders I'm fuzzy on but I think cavaliers, corsicas etc. engines bolt in, you can do an ecotech but it requires ***loads of work. There is always the Northstar or 350 V8 option ;-] The point is, with a fiero, any engine can go in, just amounts to hours and dollars...
If its low octane gas use high test. if its a rod knock and still runs you my need rod berings
Repair Help & Product Troubleshooting for 1985 Pontiac Fiero

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