cAstro my Prius c: Project thread

Here are a few more pictures to highlight the subwoofer enclosure fitment in the trunk with the foam pieces. I simply used a keyhole saw to trim away the excess styrofoam where the enclosure now resides. I started with one side and then matched it with the other foam piece.







Voila! The trunk carpet velcro's down exactly like stock, and you can't tell anything is there unless you hear it.


I also got really annoyed with the very random TPMS light occasionally blinking. It would start blinking every few days, then be off for another few days, and repeat seemingly randomly. I removed the instrument cluster, which was rather easy as all the dashboard panels snap out.

-->Radio bezel first, then passenger air duct, then big curved silver panel, then two little clips on the underside of the IP hood, then the IP bezel itself. The IP is held in with two screws, and then has two very easy wiring harness clips. The whole IP disassembles with just clips.

I took the cheater way out and painted the warning light bezel where I no longer wanted idiot lights. I removed the "passenger", "airbag ON", "airbag off", "SET", and seatbelt, and TPMS light pass-throughs. All but the seatbelt lights were unnecessarily [i.e. blindingly] bright at night as they do no dim with the rest of the IP lights. This is pretty much one of the few facets of this car where it's very cheap roots shine through. I always thought it was moronic that the car has dummy lights for a normal operating condition; the upper left dummy light is for actual airbag faults, so I left that visible. Please don't lecture me on the seatbelt light, I absolutely believe in wearing seat belts [6-points with HANS when possible] and it's completely redundant for the car to remind me. I also refuse to leave my driveway until passengers are belted too; I don't tolerate flagrant disregard for ones own safety while people are under my responsibility in my cars.

Safety disclaimer done, here are some pictures:







Taa Daa, they're GONE!



Finally, I have some 3M Di-noc carbon fiber vinyl laying around, and thought I'd see how it looked as a "blank plate" where the push-button start would've been if I bought a "three" or "four" trim level. I think it turned out nice!






Whew! That's enough for now
Cheers,
Ryan

 

cAstro is now at V2 Motorsports getting the following bits sorted:

*Whiteline front control arm bushings, both the lateral and +0.5° caster rear locator bushings installed
*Corner balancing w/driver weight
*We're going off our other FWD experience to estimate an alignment spec that seems rational. I'll post that up along with the corner weights in a day or so.

I was explaining this to a car buddy last night at dinner, and IIRC it went something like this:
Me: "I just dropped off the Prius at the race-shop to get aligned and corner balanced."
Friend: "Now there're two pronouns that haven't been in the same sentence before: Prius and Race-shop. If I didn't know you better I'd think you're crazy."
Me. "You know me, it's all about precision and maximizing the platform."

 

Quickie update: The car weighs 2,655 pounds with "me" + 3 gallons of gasoline in it. That puts the car at 2,497 pounds, which is very close to advertised weight.

Weight added:
*rubber floor mats
*chewing gum, towel, & legal paperwork in glovebox
*fuzzy bunny piggybank in center console for parking lot quarters
*loudspeakers, amplifier, subwoofer, wiring, sound damping
*flat tire repair kit + air compressor
*engine block heater
*window tint
*18 grams for uber tiny 32GB thumb drive [LOL]

Weight removed:
*light wheels & tires
*lighter suspension dampers
*spare tire & some chunks of styrofoam from the trunk foam floor blocks
*rear headrests
*owners manual [now on bookshelf]


Also of note, the car was not perfectly symmetrical in terms of front caster. This is rather common for mass-market cars. The Whiteline offset front control arm bushings were used to even out the right and left caster.

 

Yea I'll probably take it out at least once, just to see how it does.

 

Final Alignment:
Front and rear camber set at -1.2 degrees
Front and rear toe set at 1.0mm in per corner
Front Caster equalized at 5.5 degrees per side

Weights [including 140 pounds for me and ~18 pounds gas] & Ride height @ pinch weld jack points
LF = 838 pounds & 144.4mm
RF = 790 pounds & 146.4mm
LR = 538 pounds & 160.8mm
RR = 489 pounds & 160.3mm

Total weight = 2655 pounds
Cross [LF + RR] = 50.0%
Front [LF + RF] = 61.3%
Left [LF + LR] = 51.8%

Unladed weight [no driver or fuel] = 2497 pounds

The car now feels flawlessly balanced and symmetrical. Corner turn-in is crisp and precise [as crisp as the tires will allow], neutrality is good. The car still understeers at the limit, however it's now more chuckable and willing to rotate with some lift oversteer while still being very predictable. Steady state cornering is more neutral [or you can go faster before understeer happens] due to the added camber. I'm satisfied with how the car drives. It certainly doesn't have to apologize for being both fuel efficient and a respectable corner carver.

 

Happy Thanksgiving everyone I hope all had a good holiday. I took the Prius C on a 2,600 mile roundtrip journey to visit my family in Denver. Total fuel cost = $198. Average MPG = 45.8.

The car did best through MI and IL, and struggled in terms of fuel economy in NE and IA, not sure why other than bi-directional headwinds, LOL. In all, the car acquitted itself as a comfortable and quiet long-hauler. I have to admit though the tires, alignment, and suspension made a big improvement in confidence and straight-line stability, even in heavy crosswinds. A stock C [at least the crap stock alignment mine came with] would've felt skittish and unstable in comparison.

The biggest complaint I can muster is regarding the seats; they simply don't have any thigh support, and I found myself using the cruise control and then stretching and splaying my legs as much as possible to scavenge whatever little thigh support is there. I can't say I've had this problem with any of my other cars. Mainly the seat bottoms needs to be tilted aft for better posture. Nevertheless, I was able to work into a reasonably comfortable position, so I'm admittedly over-emphasizing the problem.


Also, I got my factory fill Used Oil Analysis back from Blackstone. In all it looks good. The Copper should plummet with the next change, as bearing break-in should be done now. I replaced the factory fill with Mobil1 0W-20 AFE in the car; we'll see how that goes.

 

I just wanted to share a bit of information regarding wheel & tire weights, as I got my fancy new scale a few days ago, so I've been running around weighing everything in sight.

Stock 15x5" steelies [no hubcap] w/Bridgestone Turanza EL400-02 175/65-15 = 31.2 pounds
Konig Daylite 15x6.5" alloy w/Michelin X-Ice Xi3 185/60-15 = 29.4 pounds
949 Racing 6UL 15x7" alloy w/Continential EcoPlus+ 195/60-15 = 28.6 pounds

I'm pretty geeked that I lost weight on both sets, but especially on the 3-seasons with 2" wider wheels and 20mm wider tires.

 

Oh yea, I haven't posted pictures of my winter tire setup yet! Here goes:

 

The 949's (for 3-seasons) are silver/polished, and the Konig's (for winter) are gold. They both have a double 6-spoke design, but the cross section of the spoke is a different shape. The 949's are lighter [and sexier, IMO], whereas the Konig's have more brake caliper clearance.

 

Well luckily it's winter 15 months a year here in Michigan.

I took a chance on the gold and it seems like it works OK, but the silver summer wheels are rather timeless and won't get old looking years from now.

 

Thanks, other than my C is about a half foot lower than a Fit.

I can't be sure if either of my wheel/tire setups have hurt FE, as I seemed to transition the same time as winter fuel was phased in. I'll be able to provide a more thorough answer next year. That said, I believe the Conti ProContact Eco+ are slightly less efficient than the OEM skinnies, but the Michelin X-Ice Xi3 seem to be on par with stock. This i just basing it off how fast the car can be driven in EV mode.

 

For what it's worth, there are some great other build threads on the forum, and I'm still sticking around in case I can help out with others' suspension setups