Gtidan

Originally Posted by conekiller
I'm still amazed the 250 was even produced w/the 204hp engine. If anything the 250 should have at least maintained the power output of the outgoing IS300...offering a new LARGER/HEAVIER car with considerably less power was...well...dumb.

You seem to forget the old IS300's power was rated using the old system while the new IS250 is rated using the new system. Most seem to think the new and old engines would rate about the same if you used either method on both.

TED_FR

You seem to forget that performance is not only a matter of max power but more a matter of max torque, and there the IS250 has a far worse torque than the lighter IS300. (288 Nm @ 3800 rpm for the IS300 vs 252 Nm @ 4800 rpm for the IS250) . That is where the real difference is, a lesser torque at a quite high rev for the IS250.

jezza

What you're forgetting is that HP is a contrived number based on torque. In other words, the new rating system affects both numbers.

Also, peak torque at X rpm isn't really the big factor, but what the torque curve actually looks like. I'm willing to bet the torque curve of the IS250 is pretty flat and likely carries a majority of that torque farther along the rev range than the IS300 did.