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Swapping to PM Connecting Rods - Worth It?

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Old 12-13-2009, 07:19 PM
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Swapping to PM Connecting Rods - Worth It?

I have a 305 TPI with a ZZ4 cam, TFS heads and FIRST Intake.
Rods and pistons are stock.

Just wondering if it is worth switching the commecting rods from stock to lighter PM ones.

Hoping the weight savings would add a few more HP

Any thoughts....
Old 12-13-2009, 08:53 PM
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Car: Dad's 87 Bird (Org Owner)
Engine: Vortec 350 Crate Motor
Transmission: TH350
Axle/Gears: 3.42 Posi
Re: Swapping to PM Connecting Rods - Worth It?

Only if you are rebuilding the engine anyway. I would not change the rods in a good running motor.
Old 12-13-2009, 10:22 PM
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Re: Swapping to PM Connecting Rods - Worth It?

I would not bother (unless your rebuilding). The rods only make up a relatively small part of the overall rotating mass along the driveline. Probably not much difference in power, and you would need to rebalance the rotating assembly. For reference, I recall that a stock cast 350 piston + PM rod assembly weighs about 3.5 lbs. I cant see the stock rods weighing drastically more than that.
Old 12-14-2009, 11:51 AM
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Re: Swapping to PM Connecting Rods - Worth It?

I've seen lighter cranks. That would probably benefit an engine more than lighter rods. Agreed that it doesn't make sense for rods only and if engine is running fine. Lighter rotating assembly would only help at high rpm speeds, guessing 5000+? Plus the lighter items seem to be pretty pricey.

How do you like your FIRST intake? Looking to buy one soon. Where are you in Buffalo?
Old 12-15-2009, 03:30 PM
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Re: Swapping to PM Connecting Rods - Worth It?

Thanks for the reply's guys.

The FIRST intake works great....good midrange. Better than stock and more street friendly than a HSR.

I'm near Amhurst, NY
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