The Teksid? No, they are very very strong. There is a stronger one now and I will try and remember who makes it but it was on Horse Power a couple months ago. Its a popular name though and I am sure someone on here knows who it is. It was the engine built for project Alter Ego and it made 471 hp on a Teksid with 03/04 heads N/A. Anyway he talks about how much power they can handle and that he has a new block they make (still 4.6 aluminum) thats good for over 2000 hp1800 hp? r u kidding me? i was told those blocks would crack close to 700...wow...i had no idea
But the 96-98s were stout. Rods/pistons good for 450ish at the wheels, crank good for 1200 and block good for 1500-1800 (Ive heard variances).
Gotta remember where the origins of that block are. It comes form the same place that makes Ferrari engines. The mixture of the metal in the engines is a secret.