sbc stock connecting rods

[prairiehotrodder]

does anyone know if the late 97 - 98 chevy 350 connecting rods that are used in the vortec engines are any better than the older rods ? They are a completely different design. Not sure what they call them.
Brian

[CGT]

does anyone know if the late 97 - 98 chevy 350 connecting rods that are used in the vortec engines are any better than the older rods ? They are a completely different design. Not sure what they call them.
Brian

Your talking about powdered metal(PM)rods. I have used them and have had no issue with them. Others have strong feelings against them...and anything else that's made from powdered metal as far as that goes.

[dannobee]

I've built plenty of lower division circle track engines with the powdered metal rods and have never seen a rod related failure. Put good bolts in them, touch up the big and small ends to fit your needs and run 'em.

[BillK]

GM used to have them in the performance parts catalog as a kit. If I remember correctly they used to say they were good for 500 hp. I have never seen one fail. I have seen a few out of boat engines that got hydro-locked and the rods were badly bent but not broken.

[Lizardracing]

I've only seen one set fail in a CT525 worked over by Ballwin Racing Engine's in STL. They even said the power levels of the power/refresh were pushing the limit of the rods. They lasted around 100 nights in a Super Late Model before spontaneously auto-disassembling themselves.

[PackardV8]

There's always a torque/time factor in the equation. They'd probably last forever in a well-tuned sub-500hp drag car. Then, we've heard 100 nights in a 500hp round tracker and might not want to use them in a 500hp offshore power boat which would be at max effort for hours with the occasional overspeed when it flies.

[ProPower engines]

Some engines like the GM crate program uses all have the PM rods in them.
They are the same weight as the forged rods but at specific power/RPM levels they last a long time.
In the crate races they have a RPM limit in marine engines they limit the RPM in other ways but same idea they are limited to a lower abuse rate then an unlimited RPM engine.
Piston weight has a lot to do with how long they last as well. They are more rigid then a forged rod for sure and if the piston speed or weight they were designed around is exceeded they come apart.

Marine engines will snap them if the prop keeps coming out of the water just like wheel spin of a car. free wheel then load hard will cause them to snap.
Like any part they have a life span and cycle rate. After that has been exceeded all bets are off.
I never re-use then on a freshen up because if they break its my ass that has to deal with the issue so I just replace them.
Some marine shops reuse them again during a repair but that would be the only exception is a repair not an overhaul.