Pinto_Girl's '06 #8+TRD Sportivo suspension

First off, I have to tell you that I'll prob'ly misuse at least one (if not many more) car-speak terms in this posting; hopefully you can get through all of that and extract any kernel(s) of information (if present) from the vast majority of chaff.

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I just wanted to share some observations about having 'wrung out' my '06 -- she answers to Buzz, but with this weird computer voice -- for the first time, on Highway 1, down the NorCal coast from Half Moon Bay to Santa Cruz, and back again. And how, in my opinion, she compares to before the 'change.'

Some background: Mechanically, the car is otherwise stock, approximately 1,000 miles since new. I have removed the trim rings on the wheels (there's so much talk about unsprung weight that I wonder if anyone remembers to include the weight of the beam axle and other suspension bits, but that's another story) and "pumped up" the pressure of the much-maligned Integrity tires to 42/40, but otherwise she's as I received her new.

My perception of the stock handling is that when she was driven smoothly and moderately, the car remained really, really composed and neutral, with only a little body lean and the feeling there was LOTS more available...but as the speed increased, she became rather more susceptible to an upset from a bump in the road or other unexpected event. And that seemed to happen a little too quickly and abruptly for my tastes...and at a lower speed than I'd like, too. I didn't want to find out how bad what I assume to be the typical front-wheel-drive terminal understeer would be, as we slid off the outside of a corner, either.

I guess that my goal is to make this progression a little more linear, even at the expense of a bit of comfort during everyday driving. That way, I figure, I can corner faster and not be so close to the outer limits of the car's capability...or at least approach them gradually, and maybe not get in trouble too abruptly.

I think the Sportivo suspension succeeds on this level, especially; the outer limit of the car's handling might not be that much higher than before, but I think it's lots more accessible now. The car now has a wider useable speed range.

Also, because things are under better control, the Inegrities don't (to me) seem to be nearly as much of a problem as I've read elsewhere. They don't seem to be working nearly as hard, and I no longer see (or hear) them as a major impediment to spirited driving, at least with the new suspension pieces installed.

I just kept telling myself to drive her I used to drive the Carrera: slower into, then accelerate out of the curves with the idea that I'd rather add power post-apex, than upset the car by braking early. Buzz generally seems to reward a smooth driving style (as did the Carrera), with gradual throttle and braking inputs, and a driver who doesn't let the car get ahead of her.

Seems like understeer is still the order of the day, but preliminary findings indicate that she is somewhat more responsive to managing weight transfer with the throttle. I've never yet gotten into any unstable conditions intentionally or otherwise, so I can't say what happens at that point, but she feels SO much more confidence inspiring as speeds increase and the road becomes more demanding.

As I mentioned earlier, the biggest negative issue might be that of ground clearance. I'm okay with the compromise but others may not be.

Perhaps a good way to look at this upgrade might be as a step above the '07 touring option. I haven't yet driven one, but I suspect it will fall somewhere between a 'regular' Prius and one with the Sportivo conversion

Regarding the Touring option, I feel like a good way to add stability to a car is not necessarily with bigger wheels and smaller tires (maintaining the same effective circumference and contact patch length) but with a tire/wheel combo that is larger overall. This way, the fore/aft length of the contact patch is increased, as is stability.

For this reason, I fear the 55-series tires and 16" wheels on the Touring are in some ways a missed opportunity. They may stiffen the ride and make the car *feel* more responsive at slower speeds (wondering if the suspension will have softer springs and stiffer shocks vs. the American setup, as Euro cars often have). But -- with the exception of quickening turn-in -- I don't think it may really do much to increase the overall cornering limits of the car...that is, unless the tires themselves are more optimized for handling than the Integrities (not too difficult to do, I'm sure).

Additionally, the shorter sidewalls of those 16" tires may actually make the outer limits come up even more abruptly than before...which, it seems to me, is not the best receipe for a reasonalby fast, fun to drive, predictable automobile.

The Sportivo suspension is a great way to increase the limits of your Prius -- not to mention, give it that mysterious 'what looks different?' look -- but the ground clearance issues and cost of the kit and installation seem to take it sufficiently out of the mainstream.

And, honestly, that's just the way I like it!
[big smile, and thanks to Priuschat for turning me onto this in the first place]

yours in the generation of high g-forces,
--Pinto_Girl

 

Cool; thanks...it's great to read your comments. I agree, the better damping really seems to keep things under control and lets the poor, overworked Integrity tires take a bit of a break sometimes.

I'm beginning to think that Buzz has gone from somewhat under-suspensioned, to somewhat underpowered now...

hmmmmmmm....