RE: What's STRONGEST motor for my SUMMIT??
The dewalt motors can be purchased from any place that services and repairs power tools, or online. I think sears carries them online. You will lose some speed with the dewalt motor, but only IF you keep the stock gearing. But because of their torque, they can be geared for speeds higher than the titan. I had one in a revo, geared 21/65, it was a faster setup with more torque than stock. There's a bunch of threads about installing drill motors into revo's, summitts, maxx's over on the Traxxas forums. Slight modification to one of the holes on the motor mount is required, but you'll never use that hole again for any normal motor, brushed or brushless.
Brushless is another animal. Any 1/8th scale brushless will have more torque and speed than the titan or dewalt. If you still want to do crawling, stick with a sensored setup to prevent stalling and cogging. The RX8 is the easy answer, being sensored and availible in a combo with an appropriate size motor. Castle has the Mamba Max Pro which is sensored also, but its more for lighter vehicles, and not availible in a combo with a suitable size motor. The RX8 has higher amp ratings and a stronger BEC to run all those sevo's and lights too.