aluminum rods vs. titanium rods: fatigue life

The first rule of thumb: Ti is far more ridged. Thus excellent strength to weight ratio. Your bearings aren't going to like them. But in a flat out race engine? Bearings are replaced frequently.

I run BME 7.6" Hemi rod in my high compression 451. These rods are designed for Top Alcohol. So it's an over kill to a N/A engine build. I got them for $500 on BME over stock listings. Thus I believe no brainer compared to $600+ Eagle steel rods. (All prices 5+ years ago. Im sure both all are x2 today.) The other advantage is the race Aluminum rods are very close to the same weight as stock RB 7.6". Thus I made no counter weight change to crank. The Eagles were much heavier.

So in closing? Aluminum are easier on your crank bearings than Ti. MUCH less expensive. And an over kill is available to rest any fatigue concerns. Hell, BME makes Aluminum rods for fuel cars.

Just my limited experience.