[talonxracer]

Here are two pics, showing K24A1/A2/A4 rods and BP ultralight "I"beam rods.
K24A4 vrs K24A2

BP "I" beam rod vrs K24A1 rod

 

[talonxracer]

So if anyone could confirm my assumption, the K24A2 crank is probably better designed for ~8-8.5k rpm's compared to K24A1/3/4? I could be wrong and all K24 cranks are the same....:up: or :down:

I took a K24A1 crank and a K24A2 crank to the balance shop and the K24A2 crank had far less deflection at higher RPM's, so yes the K24A2 crank is stronger.

 

[talonxracer]

The A1 crank was new and the TSX crank was a used crank.

 

[talonxracer]

could it be bc of the stonger/thicker rods? bc both cranks are have counterweights

That was both with and without the bobweights.

When I had my NIB 06'TSX crank balanced it was the closest to perfect that my balance shop guy has seen in his 30 years of balancing engines. The K24A1 crank was not and the balance changed at different RPM's, even after completely balancing it to the rods and pistons it still had deflection at higher rpm's, this told us that the TSX crank is different metalurgically and/or manufacturing wise from the A1 crank.

I doubt a basically stock rebuild would see that much difference between the cranks as long as they were balanced to the rest of the rotating assembly, but if you build it for alot more whp than stock it will show itself in longeviety and repeatable results.