With the pre-cats gone the underhood temps should reduce actually. Cats absorb and emit a tremendous amount of heat.

Those headers look amazing. I don't doubt the claimed HP gains. With factory headers our cars are trying to breathe through two 1.75" outlets. 1.75"!! The Dyno-comp headers are probably as close to equal length long tubes as we're going to get. They are certainly better than the OEM modified-log headers.

With correctly sized primary tubes, low-end torque will not be sacrificed. I'm running equal-length LONG tube headers with 1.75" primaries and 3" collectors into a 2.5" exhaust on my Corvette and it has tremendous low-end torque, right off idle. Given the length available for the Crossfire/SLK headers, I'd guess 1.625" primaries would be about perfect. 1.75" might yield a little more HP, 1.5" a little more torque.

That is a LOT of $$ for headers though. Such is the price of exclusivity I guess...