Iron Duke 85+ Roller Camshaft (Page 1/1)
82-T/A [At Work] SEP 26, 06:13 PM
Hey guys, now that my daughter has the engine out, I'm thinking machine shop work, and what we can do ourselves. I want her to assemble it herself, but not sure if I want to have her hone the block herself. I picked up a set of Sealed Power pistons for $10 a piece for the Iron Duke, and they're .030 overbore. I'm expecting a big ridge in the combustion chamber, etc... all that.

But the other thing I'm curious about is the factory cam. It's a roller cam, so I assume it has little to no wear at all. I'll be replacing the lifters, but want to know if I should consider replacing the cam. And with that... do I also replace the cam bearings? Or... is it OK for me to replace the cam bearings with a standard size and re-use the old cam?

I'd love to get something performance-oriented, but it doesn't seem like replacement roller cams are even available. Thoughts?


Thanks!!!
Patrick SEP 26, 06:26 PM

quote
Originally posted by 82-T/A [At Work]:

I picked up a set of Sealed Power pistons for $10 a piece for the Iron Duke, and they're .030 overbore.



Have you measured the cylinder bores? Are you assuming they weren't overbored previously? If they haven't been, are you assuming the cylinders need to be bored .030 over?
82-T/A [At Work] SEP 26, 09:03 PM

quote
Originally posted by Patrick:

Have you measured the cylinder bores? Are you assuming they weren't overbored previously? If they haven't been, are you assuming the cylinders need to be bored .030 over?




I'm assuming they will need to be overbored slightly. I KNOW they will need to be overbored .030 because I just bought a set of Sealed Power pistons with anti-friction skirts and all that good stuff on clearance for $10 a piece. All of that said, every single Iron Duke I've ever had the luxury of pulling the cyl head off of (3 so far), they all have this crazy ridge where the piston has worn away the cyl walls. I've not taken this cyl head off... but I'm sure I won't be wrong here.

Any thoughts on the camshaft?
buddycraigg SEP 26, 11:02 PM
If you're balls deep, then I would replace the cam bearings.

Replacing the cam is a choice you have to make.
Do you want the stock power/torque curve?
Does the cam look okay?
What RPM will you be mostly driving in (in town / highway = what transmission do you have).

Lots of things to consider.
Patrick SEP 26, 11:49 PM

quote
Originally posted by 82-T/A [At Work]:

All of that said, every single Iron Duke I've ever had the luxury of pulling the cyl head off of (3 so far), they all have this crazy ridge where the piston has worn away the cyl walls.



If so, and this duke has been previously bored .030 over, you may now have four brand new paperweights.

All I'm saying is that measurements are usually taken before parts are ordered.

[This message has been edited by Patrick (edited 09-26-2023).]

82-T/A [At Work] SEP 27, 07:24 AM

quote
Originally posted by Patrick:

If so, and this duke has been previously bored .030 over, you may now have four brand new paperweights.

All I'm saying is that measurements are usually taken before parts are ordered.





Hah... I get it, but I could tell this engine has never been removed before. Or if it has, it hasn't been removed in decades. It has at least 1/2 an inch of oil caked on.



quote
Originally posted by buddycraigg:

If you're balls deep, then I would replace the cam bearings.

Replacing the cam is a choice you have to make.
Do you want the stock power/torque curve?
Does the cam look okay?
What RPM will you be mostly driving in (in town / highway = what transmission do you have).

Lots of things to consider.




Buddy... I think I'd like stock, or even something that just gives a bit more power than a postal truck. But I'm not seeing any aftermarket camshafts that fit the Duke that are also roller cams. That's my only concern. I don't want to go to flat-tappets.

Is it OK to re-use the stock cam if it's a roller cam? My assumption is that ... at least on the journals, there won't be any real wear.
Dukesterpro SEP 28, 11:21 AM
Roller cams are A-OK to reuse if all the lobes are in spec. Just grab new roller lifters. The old ones are probably on there way out anyways as far as the hydaulic part is concerned