Shotpeen CR rods??

'strokeThis_'07

'strokeThis_'07

New member
As title says. Everyone says to run shotpeened 12v rods and skip CR rods, but is there a way to make the CR rods stronger or more apt to handle more power/rpm?

Might be a dumb question, but since I don't know, this is the place to ask
 
'strokeThis_'07 said:
As title says. Everyone says to run shotpeened 12v rods and skip CR rods, but is there a way to make the CR rods stronger or more apt to handle more power/rpm?

Might be a dumb question, but since I don't know, this is the place to ask
Click to expand...

Yes there is a way......Proper tuning!
 
Untreated stock CR rods have held up over 900hp on my end with much abuse. Maybe I am just an exception. However, the crank, not so much...:nail:
 
DIESEL_POWER said:
Yes there is a way......Proper tuning!
Click to expand...

Smarty. If EFI materializes, I'll run it

soulezoo said:
Untreated stock CR rods have held up over 900hp on my end with much abuse. Maybe I am just an exception. However, the crank, not so much...:nail:
Click to expand...

Hmm...interesting. General concensus seems to be 800 is about where they start to bend I thought? I wasn't aware of crank problems...or did you just get lucky?
 
I've never bent one. I've broken other parts but never a rod. CR's with MLS head gaskets have a tendency to blow head gaskets into the cylinder. This can lead to the bad type of water/coolant injection. Hydraulic an engine pretty much guaranties a bent rod. Here is a pic of a MLS gasket that was blown into the cylinder:
DSC00354.jpg


Proper tuning, and a solid engine and the CR rods will hold a lot of power.

Paul
 
I've got a CR rod that looks just like that on my "Rack of Shame" down at Garmons....


Just do 12 or 24 v rods.....I know I've seen some for fairly cheap...
 
Thanks fellas. I'm going to keep looking for some, but if not I'll throw the stockers back in. It'll be a bit before I need them...

Surfing forums, I've seen numerous times talk of CR rods starting to fail around the 8/850 mark. And word of mouth...not taking it for gospel, just kinda what I've heard
 
Shot peening is really meant to reduce the impact of surface defects, in a fatigue loading situation where surface defects serve as crack initiators. So while that would help a rod live a long life within its engineered limits, it's all out the window once you start yielding the whole thing.

It's like painting a house to keep a tornado from blowing it over. No worky.

A guy I knew tried it with PM Dmax rods and it bent them in short order. I know they are less robust than the CR rods, but he was also at less HP than this.

Remember, the metallurgy of the rod is compromised quite a lot in order to make the cap cracking easy.
 
nwpadmax said:
Shot peening is really meant to reduce the impact of surface defects, in a fatigue loading situation where surface defects serve as crack initiators. So while that would help a rod live a long life within its engineered limits, it's all out the window once you start yielding the whole thing.

It's like painting a house to keep a tornado from blowing it over. No worky.

A guy I knew tried it with PM Dmax rods and it bent them in short order. I know they are less robust than the CR rods, but he was also at less HP than this.

Remember, the metallurgy of the rod is compromised quite a lot in order to make the cap cracking easy.
Click to expand...

X2:Cheer:
 
nwpadmax said:
Shot peening is really meant to reduce the impact of surface defects, in a fatigue loading situation where surface defects serve as crack initiators. So while that would help a rod live a long life within its engineered limits, it's all out the window once you start yielding the whole thing.

It's like painting a house to keep a tornado from blowing it over. No worky.

A guy I knew tried it with PM Dmax rods and it bent them in short order. I know they are less robust than the CR rods, but he was also at less HP than this.

Remember, the metallurgy of the rod is compromised quite a lot in order to make the cap cracking easy.
Click to expand...


What if I use paint that has elastomer in it? LOL

Listen to this guy, he knows his metallurgy, not the mechanic who says, "huh, I think it ought to work, worked in my buddies lawn mower"
 
Also, I know a few 12v's running stock CR rods that are holding up just fine. However, they spin some R's, and don't stress them like a CR would.

Give the CR some RPM, and I'll bet the rods would hold up better. At least until they figure out the tuning for high RPM, then make even more power:hehe: Talk about a vicious circle:D

Chris
 
The only reason that these rods are failing is from bad tuning, and too much recipricating mass, nothing else!

Properly done these rods can handle about 1400hp i feel. Yes 24 and 12 valve rods are stronger, but stronger rods dont fix the real issue's, it just pushes the issue's somewhere else, and useally the failure becomes more exspensive.

Heck i run aluminum rods and turn 6k and have had success so far!!
 
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