OK, so I know the Iron Duke is a hated engine but they are out there and it is time they get a little love. I purchased a 1982 Camaro a couple months ago and have been working on getting it running right. After finding that it had a stuck valve it was time to pull the head off and rebuild it. So that is where things are at right now. While the head is off the intake is going to get ported and the exhaust manifold is getting replaced as it was cracked and broken when I bought the car.

Will try to keep this up as I do work on it and try to provide some insight to help improve these motors a little bit from what they are.

 

We had an Iron Duke in a 23' Viking deck boat. Could pull 2 adult skiers with 6 people on board. That engine had some pretty good torque. But the 19' with a 302 that replaced it did go a tad bit better!

 

They are good engines and eventually the car will get a V8 put in her but for the few years she will be a DD car I figure make the engine as much as I can since it is in a Camaro at least.

 

I would not put a lot of time or effort into the 2.5. Assuming the motor is original you do not even want to push too hard and be darn sure it stays cool. The engine blocks crack just above the lifters. We replaced a lot of engines in the mid 80's under warranty. This was caused by a casting defect on all the that was fixed in 84 but did not show up until 85 model year. If you have a replacement motor see if you can find a date stamp. I think if it is 84 or newer you ok. If it cracked early and you have a 1983 replacment the block still has the defect.

The Fiero's had the highest failure rate with Camaro's right behind it. I Asked a GM engineer why the Camaro and Fiero's where so much higher then the FWD or the S10's He said with the Fiero it was heat combind with how they where driven with Camaros it was all about how they where driven.

Another common issue was breaking head bolts. You should replace them. Even grandmothers where breaking head Bolts. I have done 2 headgasket/broken headbolts in a single day before.

The last issue was the timing gears. They can make a lot of noise and still work but it will get to the point you are scared to drive it. I have only seen them fail once. The gears come as a matched set might be worth while to replace them if you have the motor out because the process requires the cam to be removed from the engine.

Yes the Pre 80's and post 84 2.5's Are truely a bullet proof motor so if you have a 84 block with mated timing gears and new headbolts you have a 300k engine easy. I can not say I have ever seen a fast one but they will run forever.

Edit: now that I think about it the block fix might have been a little later. I can remember 84 Fiero's on their 3rd motor under warranty and back then it was 36 months 36K.

 

Thanks for the info Gorn, I don;t have the engine out right now just the head off. I am rebuilding the head right now. Not planning on pushing the engine at all as it is to be a DD car and not a racer in any way. Not sure on the date stamp right now, I can pull the casting number and look it up I guess but I am assuming that the engine is original to the car and has not been replaced.

 

The Iron Duke, up to and including 1990 had a fiber cam gear (referred to as "micarta"), with a steel crank gear. We zipped the teeth clean off of ours. You might want to check yours, or even replace it depending on the miles it has on it. With some wear/slop in the teeth, you usually zing off a tooth or more when starting the engine. No damage beyond that point, but the engine won't run. We replaced the gears with the engine still in the boat, no cam removal was necessary.