Based on my research (JWT, Unitech, the NISMO engine-builder with Kelly Racing), with replacement rod bolts both the VQ35HR and VQ37VHR are both safe to 8800rpm (although the jury is still out on running the VVEL that hard for sustained periods - there is no real empirical detail).
With OEM rod-bolts, I'd be reluctant to exceed 8000rpm, but that is just me.
Remember, NASCAR engines run 9500rpm and more for hours and they are all >3-inch stroke.
|