Ross wristpin limits

[ckrell]

I have Ross pistons with the standard pins they also have an upgrade. (4340 pins) I was just wondering, at what horsepower level would the upgrade be necessary?

 

[nitrouskris]

Well I broke one at 35psi. never put the car on the dyno

 

[bastarddsm]

If they are .150 wall 5115 steel, I'd not run them over 4-500whp. I'd keep the rpms down to 8000 as well.

 

[Archer Fabrications]

Still aren't there stock blocks making over 700hp? (Ostar) you'd think a forged setup could take well beyond it's advertised limits.

 

[twicks69]

, I ran those puny wrist pins on my old Eagle/Ross 2.3L 7-bolt to 766AWHP/713TQ for 3 years of abuse, then gave the rod/piston combo to a friend and he has been running them ever since 2008 without issues. I had over 30,000 miles on them when I gave them away. The car was doing 148-150mph traps.

Personally, I would run the upgraded pins for any real power levels; especially above 600HP @ crank.

 

[bastarddsm]

Yeah I'm sure they live sometimes, but the manufacturers say 100hp per hole on those pins, and I broke mine with not much more. Needless to say I will not run the thin pins anymore.

 

[twicks69]

Yeah I'm sure they live sometimes, but the manufacturers say 100hp per hole on those pins, and I broke mine with not much more. Needless to say I will not run the thin pins anymore.

Yeah, for our performance buildups, I would only recommend the thick-wall tool steel wrist pins. For how cheap the upgrade costs, it far outweighs replacing an entire engine if the part fails.