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#63347 02/17/11 03:31 PM
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WillH Offline OP
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Any suggestions for a better (lighter/stronger) connecting rod for a 261 Chevy. I know about the GMC rod/Buick piston option; actually working up a set of rods right now but this is, sort of, on the heavy side. I just read the posts on the 302 GMC rods but the same rod options don't seem possible with the shorter deck height of the Chevy. Ideas and information appreciated. Thanks

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I've researched this idea for a long time. The GMC rod swap is the only economical choice for the Chevy engines. You can offset the total rod and piston weight some by going with a custom piston, but thats about the only choices out there. Custom billet steel rods aren't going to be much lighter either than the stock 261 or GMC rods. So the lighter custom piston is about the best way to reduce the overall weight significantly.



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WillH Offline OP
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Looks like I'm stuck with the GMC/Buick combo; heavier than I would like but very economical compared to custom parts. I haven't bought pistons yet so I don't know the actual rod/piston weight; The stock GMC rod is slightly heavier than the stock 261 but the Buick piston must be lighter than the Chevy so it may end up about the same; still heavy. It's basicaly a street engine so with close attention to details...............

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Not all Jimmy rods are the same, look for the "419" rod (.990 pin, if memory serves me). By the time you clean it up it's not too bad running the Buick wrist pin.

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The GMC rods I am using are the "419"s; They are 7" C to C; same big end bore as the 235/261; need the big end narrowed to 1.24 and the pin bore bushed to fit the Buick pin. The "GMC by the numbers" web page list these as "late 270/early 302; .990 pin bore; narrow bearing tab", however these rods have the wide locking tabs (approximately .250); I am wondering if I have an odd set of rods or if the web page information is wrong. I don't know that the locking tab width makes any real difference.





quote=Armond, II#298]Not all Jimmy rods are the same, look for the "419" rod (.990 pin, if memory serves me). By the time you clean it up it's not too bad running the Buick wrist pin. [/quote]


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