Just across town, there is a 455 on the stand with a set of Crower I-Beam Rods. It spun the #1 and #2 main bearings and destroyed the crankshaft. We are seeing a lot of this on the local Pontiac scene and it has nothing to do with rod material.
I would not suggest spending more on a set of stock rods than you could buy a new set of Crower's for. That would be ridiculous. In my case, I do my own work, so the stock rods are cheap.
Almost everytime I have seen a rod failure, there was evidence to support a detonation condition, poor/improper assembly, oiling issues or overrevving.
Never, ever saw a problem with a 389 Pontiac. I have built several of those engines over the years (stock restorations) where the owners drove the hell out of them. Never saw a rod failure.
I built one 389 in particular for a gentleman. It was a 1965 GTO body-off restoration done by our shop. When it was done, he really abused this car. About 2 years after delivery, he complained about 1/4 mile performance. I drove down to Bakersfield Raceway and went for a ride with him.
Every shift, he revved the 389 until it would rev no more...the front end of the car would just lay down...and he was burrying the tach. I asked him why he was doing this as I felt the 389 was over and done with past 5300. He felt he was 'getting every last drop' out of the engine and had been driving it like this for two years.
I made a few passes shifting at 5500 and the 1/4 mile times immediately improved.
That engine, built in 1986, is still running and being taken to the drags on a regular basis.
I think a Chinese rod is OK as long as you bake them in an industrial oven for 8 hours at 400°F to stress relieve them. Smokey Yunick used to do this to SBC rods and it is detailed in a few publications. We started doing it on Flathead Ford V8's when I was working for the family business in high school.
Immediately after cooling them natuarlly, I would resize them to the low side of the tolerance.
The answer depends on how much you have to spend and what you intend on doing with the engine. That's just my take on the subject...Robert
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