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So I know that Edo hosted a thread covering some info on the RDX crankshaft a little bit ago, and many people have tried to bring it back from the dead because it was of such interest.

From the other thread:

"The RDX uses a forged-steel crankshaft with a long 99mm stroke. To reduce friction and improve durability, the crankshaft journals are micropolished. Special forged connecting rods are engineered for the engine's high power output. The RDX has special alloy pistons with thick crowns and super hard Ni-P plating in the piston ring grooves to provide a long-wearing surface with extra heat resistance. A high-capacity oil pump supplies oil jets directed at the underside of the piston crowns to help dissipate heat." - Source

B/S - 86mm x 99mm
Rod Journal - 0.780"
Wt. ~37 lbs (2 lbs less than TSX Crank)
Oil Pump - 15100 RWC A02

"All journal dimensions same, all rod bearing part numbers same for both TSX & RDX. TSX uses PRB mains, RDX uses RAA mains."

*The above was summarized from the other thread for future readers

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My question is if the RDX's crank is stronger and lighter than the TSX's, would it be safe to say that all you would need to do in order to use it is swap the cranks...or is the above write up telling me that this form of a swap would req. "special forged connecting rods", "alloy pistons with thick crowns and super hard Ni-P plating in the piston ring grooves", and the "high-capacity oil pump" with the oil squirters we already see in some K-series blocks to make it a smart, functional improvement.

And if so, do you believe it is worth while on an all motor build. The fact of the matter is I will most likely be getting custom pistons, and rods anyway for my build and I just thought...why not the RDX crank. If there is more I should know, please enlighten me.

PS - A link to a lot of RDX overview information from another forum
 

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i've been wondering this for a while as well! i always heard it was lighter but never any of the other info mentioned here. definitely something to think about.....and not badly priced either. :up:
 

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so.... its 2 lbs lighter. is it worth the money for an NA build? what kind of gains would that realistically net on a simple k24a2 setup with OEM pistons, and maybe some cams?

maybe this will only benefit the turbo guys that need the lighter weight AND a stronger crank. I dont see myself breaking my TSX crank anytime soon...
 

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so.... its 2 lbs lighter. is it worth the money for an NA build? what kind of gains would that realistically net on a simple k24a2 setup with OEM pistons, and maybe some cams?

maybe this will only benefit the turbo guys that need the lighter weight AND a stronger crank. I dont see myself breaking my TSX crank anytime soon...
damn, 2lbs lighter on the rotating assembly, i'd definitely say it's worth it!
 

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damn, 2lbs lighter on the rotating assembly, i'd definitely say it's worth it!
x2. If you had the lightest rods and pistons available, I don't think you could get rid of 2 lbs.

Add the K20A light weight flywheel and you loose more weight while using all OEM Honda parts. :up::up::up:
 

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so.... its 2 lbs lighter. is it worth the money for an NA build? what kind of gains would that realistically net on a simple k24a2 setup with OEM pistons, and maybe some cams?

maybe this will only benefit the turbo guys that need the lighter weight AND a stronger crank. I dont see myself breaking my TSX crank anytime soon...
actually I think an N/A build is exactly the perfect reasn to use lighter components. We N/A guys have to make use of every single advantage we can get,there is no upping the boost for us. N/A is'nt cost efficent and that is well known,but for the guy that wants the best of the best while using oem parts I don't think it's a huge price to pay.
 

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actually I think an N/A build is exactly the perfect reasn to use lighter components. We N/A guys have to make use of every single advantage we can get,there is no upping the boost for us. N/A is'nt cost efficent and that is well known,but for the guy that wants the best of the best while using oem parts I don't think it's a huge price to pay.
i completely agree with this! couldn't have been said better :up:
 

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anyone know any more info on the rdx rods? are they better than tsx rods? looks that way from above post.
 

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Just so that the answer is written in plain letters:

Can we say K24 from CRV/element/accord could receive a RDX crank, 2009 tsx pistons and rod?

I didn't want to go the "buy the engine part by part" way but this seems like a darn nice set up...
 

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actually I think an N/A build is exactly the perfect reasn to use lighter components. We N/A guys have to make use of every single advantage we can get,there is no upping the boost for us. N/A is'nt cost efficent and that is well known,but for the guy that wants the best of the best while using oem parts I don't think it's a huge price to pay.
totally agree, I would just had to drop the cash on the crank, and not have it count on the dyno.

But that is a very good point that even with the lightest rods and pistons around, you aren't saving 2 lbs. makes me want to try it.
 

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Just so that the answer is written in plain letters:

Can we say K24 from CRV/element/accord could receive a RDX crank, 2009 tsx pistons and rod?

I didn't want to go the "buy the engine part by part" way but this seems like a darn nice set up...
but oil squirters in the TSX block are nice, especially on OEM cast pistons that can't take the same head of forged pistons.
 

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totally agree, I would just had to drop the cash on the crank, and not have it count on the dyno.

But that is a very good point that even with the lightest rods and pistons around, you aren't saving 2 lbs. makes me want to try it.
you won't really see the difference on a dyno with a lightened flywheel either,but it will transform your driving experience on the street/track.
 

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^^^exactly, i don't really care about hp #'s, i'm excited to feel what lighter parts on the rotating assembly feel like on the butt dyno.
 
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