XE282S in my 408??? Big enough or bigger?

The reason I say more gear I think it's pointless going a bigger cam and stay with same gear, everyone talks about engine torque but its the torque that reaches the ground that matters. Say your engine produces 530lb-ft and say you have a 1st gear of 2.74:1 and rear gear ratio 3.91:1 that 10.71:1 overall times 530= 5678lb-ft to the rear tires now move up to a 292 cam might gain 30hp up top but loss 30lb-ft down low so 500 x 10.71:1 = 5355lb-ft going 4.10 would bring you back to 5617lb-ft. Since in a drag race your engine might be in the top powerband for 2sec's of the run your car maybe slower overall but losing some torque also might help if you can't get her to hook up.

I would run the cam you got start doing some runs than decide which way to go with cam, gear and converter, see where your cars lacking