Are polished stock rods stronger than unpolished stock rods?

[pj91gsx]

I heard that if you polish stock rods that they will be more durable. Has anyone else heard this? I'm thinking if you sand all of the grooves out of the pistons they will be more durable.

 

[h8r]

Shot peened rods are stronger, as far as polishing? Hmm.. A balanced rotating assembly is the most important step for durability IMO. The lighter the bob weight the easier on parts.

 

[gixrman]

I would not be sanding anything out of the pistons. ^ is correct shot peening the rods does help. I would not be grinding or sanding on anything that goes through the stress that rods and pistons do.

 

[pj91gsx]

ok. What is shot peening rods?

 

[GVR4592]

Polishing can prevent cracks from forming if it's done correctly. Shot peening is blasting a part with steel shot. The purpose is to from a compressive layer that is stronger and more durable.

If you polish, shot peen and add ARP rod bolts, the stock connecting rods could handle a ton of power. But doing all of that cost about as much as a set of aftermarket forged rods. Polishing by itself wouldn't really do anything because the factory rod bolts will break before the rod comes apart..

 

[pj91gsx]

interesting... How much is it to shot peen a rod?

I am going to use ARP bolts. So would it help to polish the rods and use ARP bolts?

I am talking about just sanding and polishing all of the grooves out of the rods and making the rods smooth.

 

[92trbolzr]

well there are different types of polishing what type of polishing are you talking about. most types of polishing just makes it cut through the oil better. but some do add to strength

 

[gixrman]

Your going to have to have your whole rotating assenble balanced again if you do that. Shot peening just hardens the surface so theres no weight change.

 

[Nvisabl]

I heard that if you polish stock rods that they will be more durable. Has anyone else heard this? I'm thinking if you sand all of the grooves out of the pistons they will be more durable.

Polishing , shot peening, cryo treating all go aways to strengthing metal, metallurgy is for those who know what they are doing not the average back yard mechanic. You can purchase scat rods for $370.00 I would dare say you would have more then that in machining stock junk. IMHO

DJ

 

[pj91gsx]

I do have a friend and his dad owns a machine shop, I don't know if he shot peens rods though. How much to shot peen a rod? I am going to get my bottom end fully balanced before I put it back in anyway. I'm just thinking of what else I can do. Also I want to use the stock rods so that if I decide to race at VIR, then I wont get bumped up a class for forged internals.

 

[gixrman]

I have'nt been to the track yet but how are they going to know if you have forged internals? Also price is going to depend on the shop. make some phone calls.

 

[pj91gsx]

Idk much about how they know what is done to your motor at the track. I just know that I could get bumped up a class for forged internals. Ok. I'll see what I can find out.

 

[JamiesTSI]

The machince shop I use charges $30.00 to shot-peen all four stock rods.

 

[h8r]

I agree about shot peening rods for stock internal racing classes... The Stock appearing drags mandate stock stock internals. So, for those guys it may be worth it... GM pink rods are shot peened to strengthen the surface as stated. Some engines use powdered metal rods to at strength. I agree just spend the 375 dollars on a set of eagle or scat rods with nice ARP Bolts.

 

[pj91gsx]

cool. 30 is not bad. I'm going to try that, if I can find a local machine shop that does the work for that price.

 

[91gsxnoob]

I polished and balanced my rods at my shop and am currently having them shot peened. The first place that a stress crack will form on a rod is in a groove left across the rod beam from the initial forging process. Removing these will evenly distribute the stress along the rod allowing for better longevity. I plan on busting into the 10's with my stock rotating assembly. Oh start with polishing the beams and wait to polish the ends so that you can use that weight when you balance them. The builder that is overseeing my engine balances them within .03 grams, so take your time it's worth it.