When you add weight to tires/wheels (read unsprung weight) you're going to significantly slow things down. For instance I had some 24-25 pound tires on my car last year (vs 18 or so stock) and I could feel a decent slow down. The tires were the same outer diameter as well.
That said I would really like the have a 4-wheel like he has. That T-rex thing half way down the page is amazing.
That said I would really like the have a 4-wheel like he has. That T-rex thing half way down the page is amazing.