The 4age weighs the same as the better engine... Nissan`s ca18de. The ca18de is 1800cc has bigger everything and the first was released in 1980 as a sohc. So you can get away with the same mods as a 4age and get more power. The only problem are the hydralic lifters. Steve Newing has eliminated his competition in heavier stanza coupe with a ca18de with a reliable 230hp at around 8000rpm, He thinks 260-70hp is easily achievable but at the expense of a short power curve.