Crane Ductile Rockers discontinued

[Glenwood]

So I decided to do some pre-spring checking and pull the rockers I installed last summer since threewood had experienced failures with his last year. I had already bought mine, so I went ahead and installed them. Unfortunately, I found the same problem with mine with very little run time. Really sucks!
I contacted Crane and they discontinued them a month ago apparently. They must not have been hardened properly to wear so fast.
Now I have to replace them and probably the bloody pushrods again...not happy. What to use?

 

[beanhead]

Unless you need brand-spankin'-new, these look like a good deal? Similar to the Cranes you have...
https://www.forbbodiesonly.com/moparforum/threads/big-block-isky-rockers.168438/

 

[PRHeads]

If they’re being used with Stealth heads, it wouldn’t surprise me if the cause of the problem was the smaller contact area of the Stealths 11/32” valve stem vs the 3/8” stem the OE heads have, that the rockers were designed for.
Additionally, the recent two sets of Stealths I’ve had here have a fairly substantial chamfer at the valve tip, which makes the contact area even smaller.

1st pic- Stealth valve tip
2nd pic- Stealth valve tip compared to Ferrea 3/8” valve tip

 

[Glenwood]

they are sidewinder heads which also have 11/32" stems. I didn't realize they were smaller than OEM.

 

[Glenwood]

they are sidewinder heads which also have 11/32" stems. I didn't realize they were smaller than OEM.

I don't see a chamfer but then I'd need a magnifier these days! If that extra 1/32" dia. is a contributing cause, then other ductiles like isky might also be a problem? So I'm looking at rollers or back to the stamped.

 

[threewood]

Damn, that sucks!!! Glen, I have my replacement set sitting in a box un-used that I could give you a nice deal on if you are willing to try another set. The rep told me they had previously had hardening issues. These took forever to get made after I sent them mine.

 

[Glenwood]

Thanks Mark but I dont trust them. Fool me once, shame on you as the saying goes. At least Summit is refunding or offering a discount in another set. They are a great company to deal with. Typical great American customer service.

 

[threewood]

I understand completely.

My Hughes rockers are going strong, no issues at all. My second choice would be the Mancini offerings. I did have to order new pushrods.

 

[Cranky]

Unless you need brand-spankin'-new, these look like a good deal? Similar to the Cranes you have...
https://www.forbbodiesonly.com/moparforum/threads/big-block-isky-rockers.168438/

I've used those on a 7300 rpm engine using a .660 lift Isky roller cam. Got them used and looked very good and ran them for a season with no issues. I like the hardened tip vs the Cranes without the tips....and they stayed adjusted.

 

[khryslerkid]

I wonder if valve stem caps could be used?

I have an older set of Crane rockers on standard valves, but I'll be inspecting them.

 

[Glenwood]

Im more concerned about metal floating around in there now. What a pain.

 

[khryslerkid]

Im more concerned about metal floating around in there now. What a pain.

They are more than likely very fine particles if any. Change your oil and filter. Take your filter apart and check the element for metal. You can do a visual on your cam lobes for scaring.

 

[Glenwood]

A small magnet picked up particles in the head valleys. Nothing too large but I imagine this crud can work its into the bearings. The whole thing has got me thinking about a cam swap to a solid cam.

 

[lewtot184]

this is the nature of the beast. those ductile iron rockers use a late '50's-early '60's design/technology. there was never fast cams or heavy springs back then. if you want those to be somewhat reliable use moderate lobe profiles/lifts, lower spring rates, and be sure you'll never get close to coil bind. I use them, have used them, and have had to throw them away. if the tips don't go bad the fulcrums do; and most of the time both. never use them with a high lift cam. don't understand the love affair with them in conjunction with a modern fast rate high lift cam.

 

[Glenwood]

What do you consider a high lift cam to be?
I thought my 494/513 lift was reasonable for these rockers. The springs are 924s at [email protected] height and 347lbs rate i believe.

 

[Lelo 500]

Just got done getting my new iron Cranes all set up with custom pushrods, machined shaft hold downs, and spacers. This thread is really bumming me out.

 

[Glenwood]

I know how you feel! It was painful getting it all together last year and now I have to go throught it all over again. My fantasy of driving the 64 early after the snow clears for a change just vanished.

 

[PRHeads]

What do you consider a high lift cam to be?
I thought my 494/513 lift was reasonable for these rockers. The springs are 924s at [email protected] height and 347lbs rate i believe.

I wouldn’t have expected an issue with those lifts and spring loads, and it’s certainly possible the rockers are just soft.
But, I wouldn’t risk another set at this point, unless perhaps you found a used set that had enough miles on them to prove they’re properly heat treated, but not so used the ID is all galled up.

The older Isky iron rockers have an attached hardened tip.
The set I have, the bodies were way wider than the Cranes, and I ended up modifying them so they were the same width as the Cranes.
The last set of “Isky” rockers I saw came in an Isky box, but where actually Crane rockers inside the box....... and that was quite a while ago.
I bet the actual Isky rockers haven’t been made in over 20 years.

I usually use the Mancini rockers for the milder street, street/strip type stuff.
I consider those the modern day equivalent to the old Crane Gold roller rockers.

if the tips don't go bad the fulcrums do; and most of the time both

Seemed that way to me as well.

 

[beanhead]

A small magnet picked up particles in the head valleys. Nothing too large but I imagine this crud can work its into the bearings. The whole thing has got me thinking about a cam swap to a solid cam.

....aaaand so it begins! Careful or you'll end up knee-deep in a full high performance rebuild!

 

[1968rt]

I have run crane rockers for years with over 450lbs over the nose with no problems. Its definitely a hardness problem. The 924 springs barely push 300lbs at.500