I stand by my statements. This vehicle, being as heavy as it is, needs low and mid range power and torque more than it needs high rpm power, FOR NORMAL EVERYDAY DRIVING.
In the late 1970s, I owned a Lincoln Town Car with a 460 cu. in engine. At peak power, it made well under 200 hp, but it had LOTS of low and mid range power, because of the generous displacement and realistic gearing. It was a pleasure to drive because it felt responsive under normal everyday driving conditions.
Objectively, it was slower from 0 to 60 than an 04 SSR, but under every other driving condition, it felt much more "powerful" because of the shape of that engine power curve and the gearing.
I have modeled the 03-04 SSR in my computer performance modeling software (I run a web-based small business that offers a re-gearing service to owners of fast motorcycles and cars). It turns out that the SSR needs not a 4.11 axle, but rather a 4.56 (still only 2900 rpm at 80 mph). That gearing knocks o.75 second off the 0 to 60 time.
The reason for this rather spectacular improvement is the combination of a rather high rpm engine (our LM4 engine has its peak torque at 4000 rpm and peak power at 5500), and the EXTREMELY wide range of the automatic transmission, whose internal ratios range from 3,60 in 1st to 0.70 in overdrive. This is, as one gearing manufacturer describes it, "the widest range on the planet". It is definitely NOT a "performance" gear cluster.
It's not just the SSR that benefits. I spoke with a Corvette high performance shop yeterday in fact about gearing also, They are routinely doing C5 conversions to 3.73, and the owners of the cars, especially the ones who were initially skeptical, are loving the results.
The reason that regearing is so effective on many modern cars and bikes is that te factories are making the gearing VERY tall in order to artificially improve their emissions, noise, and EPA mileage scores. When you regear for sensible "real" everyday use, the results are often spectacularly good. In fact, besides performance improvements, do NOT assume you will lose gas mileage. On many vehicles, the mileage IMPROVES under REAL world conditions, because the original gearing is targeted at an artifical test procedure rather than real world.
I have lots of motorcycle clients who have sent me testimonials.