Hello everyone so with my 84 fiero I bought to rebuild the engine was junk so I bought a new junkyard engine to put in with my buddy but he thought that we should take the whole engine apart and put all new bearings and stuff in so as I did not know much I agreed and then my buddy had no time at his shop to let me work on it so the project sat for a long time and in the process 4 of the main cap bolts for my iron duke are missing and was wondering if anyone know the exact bolt size or where to get new ones? Any input is welcome

quote Originally posted by RYLEECOOKE: Hello everyone so with my 84 fiero I bought to rebuild the engine was junk so I bought a new junkyard engine to put in with my buddy but he thought that we should take the whole engine apart and put all new bearings and stuff in so as I did not know much I agreed and then my buddy had no time at his shop to let me work on it so the project sat for a long time and in the process 4 of the main cap bolts for my iron duke are missing and was wondering if anyone know the exact bolt size or where to get new ones? Any input is welcome

s10 iron duke in junkyard.
if you cant find any i have a set in the "fun" bucket i can sell you for 20 plus shipping

My junkyard wouldn't sell me just the bolts

i thought rock auto would have them but no.someone here has a junk motor im sure.

M11x1.5x70

I would take Carter up on his offer that way you get OEM bolts.

quote Originally posted by RYLEECOOKE: My junkyard wouldn't sell me just the bolts

dont pay for them? it fits in a pocket. or like stick them with another part in a bag and say they went to it like be creative and play the system a little, i bought a full 5 gallon bucket of bolts for 20 bucks and threw a starter in the bottom since they did scrap price anyways.
edit: reading it back and 10 minutes later it seemed like rude wording but my main point is theres a bunch of ways to actually buy it if you really need to.

[This message has been edited by cartercarbaficionado (edited 05-07-2025).]

There are all kinds of Iron Dukes at Gibsons's Salvage in Neenah Wi.

I would not consider a Duke rebuild without all the internal parts. Also be advised that not all Duke engines will interchange with the version in the Fiero. Some use a completely different intake manifold and the Fiero intake manifold may or may not not bolt up to some. Check this out before you buy a core. As for mixing internal parts from one engine to another like bearing caps that is a not a good idea. If you do a Duke rebuild correctly with a cam and headwork you could get up to 110 HP but the redline will still be low.
some really good info here
Iron Duke Resource Site

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