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RB26 bottom end rebuild q's rods/pistons

BigMicky

By BigMicky,
in Engines & Forced Induction

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Roy Grand Master

Roy

Posted
Posted

Ok, so if the std GTR rods can handle enough power for a certain application, is there any weight advantage to be had from using say Eagle rods?

By the time you buy rod bolts, clean up the std rod, the leap to an Eagle rod isnt that great...so whats the drawback? Is it definitely as strong as the std rod, is it heavier?

proengines Rising Star

proengines

Posted
Posted (edited)

It's a fair difference, I just weighed a standard rod at 637.5g and an Eagle rod at 495.3g. A 142.2 gram weight saving is fairly impressive! If you want end to end weights let me know and I'll measure one up.

Edited by proengines
proengines Rising Star

proengines

Posted
Posted
End to end Weight :P

LOL...what does that tell us? Based on the weight difference, then that just about makes up my mind.

BAsed on what i found on the weight of the pistons, forgies seem heavier then std, so will help compensate i suppose.

It's the way you balance the rods, they hang on a roller bearing mandrel, one end on the scales and one off. So you get all the little ends the same weight and then all the big ends the same weight. it's because the little end of the rod reciprocates and the big end rotates with the crank. It's more critical on V engines as you use percentages of each to work out the weight of the bobweight you use when balancing the crank.

None of that is probably relevant, but if the little end if heaps lighter it's like having a lighter piston in there, so the actual weight that is changing direction at tdc and bdc is less.

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