Torque peak would be different. As an example, here's the Montero/Raider compared to a 3000GT SOHC 12v:

Montero/Raider
143 HP @ 5000 rpms / 168 lb-ft @ 2500 rpms

3000GT SOHC 12v
164 HP @ 5500 rpms / 185 lb-ft @ 4500 rpms

I'd guess the Diamante specs to be similar to the 3000GT.

Frank

'89 [color:"white"]G-Raider[color:"white"] [color:"black"]Supercharged 3.0L, MegaSquirt 2, lockup A/T, 2.5" exhaust, 172k, Cibie H4s/Oscar SCs, Hella Micro DE fogs, Cobra CB, Superwinch hubs, LSD rear/Aussie Locker front, Bilsteins, Lifeline AGM, Rust-Oleum