Important Rod information!!

**blackSS01** · 01-22-2010, 02:53 PM

I found this is a LS1/LS6 book that was written by Performance Engine builders and also GM designers that designed the Gen III V-8's and it looks like our Connecting Rods are forged from the factory and will handle 600hp all day when bolts are upgraded. Tell me what you guys think

"Automotive enthusiasts have found that "cracked," powdered-metal Gen III V-8 connecting rods weigh less and handle just as much power if not more then the famed Chevy "Pink" rods. In case you're wondering, the Gen III V-8 rods are called a cracked rod because the big end cap of the rod is created through a cracking process. It goes like this- after the rod is created, a groove is machined on the inside diameter of the rod's big end where the parting line is intended. Then, a side load force is applied to the rod to split off the cap portion of the rod. When torqued in place, the two pieces mate up precisely and lock tightly together on the jagged micro-edges of the break.
The rod itself is made from powered steel that is packed into a mold under pressure and heated to just below the melting point of the steel to get the steel to bond. A forging process is then performed, followed by shot peening, to end up with a rod of very predictable size and weight. This eliminates the need for material pads at each end of the rod (like on the pink rod) and machining to get the proper sizing, balance and lengths."

What does everyone think about this info, sounds to me like we have forged rods

And that micro edge clamping sounds like a awesome fucking idea

**pajeff02** · 01-22-2010, 04:33 PM

Forged rods are created with an entirely different process than powdered metal rods.

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This is a description of "forging": http://en.wikipedia.org/wiki/Forging Granted, both utilize pressure to create the rod, but you end up with different grain structures and properties. A friend manages a local powdered metal facility and I have watched the process from start to finish -- it is amazing to see.

**blackSS01** · 01-22-2010, 05:05 PM

Originally Posted by blackSS01

A forging process is then performed

Wouldn't that mean its forged. We tempered metals in Physics back in highschool and we would get it red hot then cool quickly which made the metal extremely strong/hard but not flexable and brittle, if my memory serves me correctly

It also goes on to say in another chapter that 600 hp FI/NA has shown that the rods can handle it, not the bolts. They do say if your building a all out track car that you may want to upgrade the rods

**pajeff02** · 01-22-2010, 05:39 PM

I agree that a step of the PM process includes "forging" of the part, but the end result is still going to have different characteristics than a purely forged part. Any metallurgists on the Board?

**jb3golf** · 01-22-2010, 06:02 PM

Your right on the info.....I have multiple books on our engines....the Rods are very strong, BUT the bolts become a liability ESPECIALLY if you have a 98 model year (which I do

). A simple (NOT SIMPLE AS I PERFORMED THIS INSTALL!!) ARP rod bolt replacement allows our cars to handle UP TO 550 (safe number).........The later LS1 & LS2 rod bolts are good up to 450 (safe number).........Anything ABOVE these numbers would be pushing the limit.....

**0rion** · 01-22-2010, 07:50 PM

the more you read about these engines the more impressed you will be. GM hit a home run with the Gen 3's. You go back 40-50 years and people would barely recognize this as a GM small block because it's so different.

**jb3golf** · 01-22-2010, 09:37 PM

Yep...the funny thing is how EASY they make power with simple bolt-ons......unreal......What I've also found interesting is how STOCK LS1 F-body's dyno VERY close to the STOCK Vette of the same year!!! I mean they certainly UNDER RATED the horsepower for our cars!!!!

**blackSS01** · 01-23-2010, 02:23 AM

I ended up buying the book. It has sooooo much info that I will be a master at the LS1 motor

**pajeff02** · 01-23-2010, 04:22 AM

Originally Posted by blackSS01

I ended up buying the book. It has sooooo much info that I will be a master at the LS1 motor

That's the first thing I did after we bought our car -- I purchased two books on the LS1 and a set of factory service manuals. I have since added two more books on tuning to the collection. All have helped me quite a bit.