Lightened Yaris

[HTM Yaris]

I say the roof weighs close to 300 lbs ( actual roof , glass, hatch, and panels etc) , but I doubt anyone will cut off their roof so we could find the exact weight

Also by definition any time you remove weight from the center of any object it makes it top heavy . You are correct in thinking the Yaris won't tip over at every turn by losing 111 lbs , but I am correct in saying it won't be a fun drive in a lightened Yaris on a 12 % grade in icy/windy conditions . Not to mention big rigs blowing past you and pushing you around .

To answer the ride quality question , the heavier Yaris will give the better ride quality . Go try it out for yourself . Just ride in you Yaris by yourself . Then ride with 1 or 2 adult passengers in the back seat . You will feel the difference fo sho .

Here in South Carolina , we don't have car inspections . But if we did and I wanted to remove the pass. airbag , I would be smart enough to remove the indicator bulb as well

Oh about the flywheel , true you can lose a lot of rotating mass , but the trade off is drivability . IMO the stock Yaris flywheel is perfect . With a light weight flywheel you will have to "blip" the throttle to match revs to make gear transitions smooth . With the stock flywheel the weight of it keeps the momentum up making gear changes much smoother .

[why?]

Originally Posted by HTM Yaris

I say the roof weighs close to 300 lbs ( actual roof , glass, hatch, and panels etc) , but I doubt anyone will cut off their roof so we could find the exact weight

Also by definition any time you remove weight from the center of any object it makes it top heavy . You are correct in thinking the Yaris won't tip over at every turn by losing 111 lbs , but I am correct in saying it won't be a fun drive in a lightened Yaris on a 12 % grade in icy/windy conditions . Not to mention big rigs blowing past you and pushing you around .

To answer the ride quality question , the heavier Yaris will give the better ride quality . Go try it out for yourself . Just ride in you Yaris by yourself . Then ride with 1 or 2 adult passengers in the back seat . You will feel the difference fo sho .

Here in South Carolina , we don't have car inspections . But if we did and I wanted to remove the pass. airbag , I would be smart enough to remove the indicator bulb as well

Oh about the flywheel , true you can lose a lot of rotating mass , but the trade off is drivability . IMO the stock Yaris flywheel is perfect . With a light weight flywheel you will have to "blip" the throttle to match revs to make gear transitions smooth . With the stock flywheel the weight of it keeps the momentum up making gear changes much smoother .

I can't say anything to 12% grades or seriously windy conditions, as I don't think I've ever driven on a grade that steep for anything longer than an 1/8 mile or less probably, I have never had a problem with wind at all with the Yaris. And I've never had a problem driving by big rigs, something i did a ton of when I drove from orlando to mass.

You are technically right about ride quality. That depends what type of ride quality you are looking for. If you are looking for super cushy, then don't touch anything. I have had 3 people or more in my car 2 times in the 4+ years I have owned it. I enjoy the ride better with all the crap out of it, where I here all the road noise and stuff hitting off the bottom of the car. I find that cool.

You're funny. In Mass, they attach the car's computer directly to an inspection computer, so they'd see the code.

The thing about rotating mass is spot on. Lightened pulley's and a lighter flywheel make the car harder to drive, and make the idle kinda nutty. For me the trade off is worth it, for others, maybe not.

[Idahotom]

CG?? Not enough to matter, besides I'd bet the CG is pretty much AT the seat level, what with the heavy engine and running gear. I had a high cross wind the other day, and yes I did get pushed around some, but do not know how it compared to a fully loaded HB as I am new to the genre.

The thing I really like is how well it coasts: I have a few places on a road I drive a lot, where I can put it in neutral, and maintain the speed limit for a mile, only slowing as I near a stop sign, as the slope pretty near matches the drag. I've done this for years in all my rigs on the same road, but the Yaris, probably mostly because it appears to be a pretty low drag rig, goes the furtherst.

Just today I went down the mountain (1,000' drop), into town 12 miles at 49 mph (on a state road posted at 45 that everyone drives 50+) and all around town running errands, then the same in reverse (not the gear, but order). 39 miles according to the calibrated Scan Gauge, and 51.8 MPG. No radical techniques were used just mild/unnoticable to others basic hypermiling. Windows down with the extra drag of the dog hanging his head out.

[HTM Yaris]

yeah I love to drive by myself without the radio on just to hear all the car sounds .

I have notices that the Yaris utilizes the slipstream(drafting) very well . I mean staying a few car lenghts back not right on the bumper . I'm always finding myself "easin" up on the gas when someone is in front of me , b/c Yaris sneaks up on the vehicle ahead of me .

[HTM Yaris]

True CG is right about seat level on the transverse plane ( up , down ), but on the coronal plane ( front, back ) you have basically added 90lbs to the front . The effect of the weight reduction won't come into play until you get to a panic situation . If you ever have to make a quick lane change or a quick lane change with heavy braking you will encounter severe understeer . Also if you change gears on a turn you will encounter oversteer . I mean that the over/under steer will be more pronounced than usual .

Idahotom , check out this vid of me on track . In this vid I have done the exact same weight reduction you described . Pay special attention to 1:03 to 1:08 . That oversteer came from me just releasing the gas while turning . If I had been on stock tires the car would have probably oversteered past the point that I could recover .

http://www.youtube.com/watch?v=UCdCdT972Uk

Try a track day or autox to learn about your car's abilities . You will definately have fun while learning about your handling . Not to mention you will meet some pretty cool people .
Oh if you do decide to do Track/Autox ... your dog will need a helmet

[Idahotom]

I see what you mean, but as the coronal datum point is somewhat unknown (?) the net effect is probably less then 90 lbs., it all depends on the length of the lever arm of course. In other words, if the CDP is close to the rear seat, removing the seat would have less effect then if it (the CDP) was several feet further forward.

Having said that mouthfull, I agree that the loading is altered, and the handling. No tracks around here, but winter snow and twisty mountains roads substitute pretty well. At the outer limits of control, either track driving or a panic situation, it could well make a difference. So... did you put your seat and the other stuff back in due to your track driving insights, or is it just something to keep in mind when pushing it to the limit? I sure like the lightness as is.

The GREAT thing about hypermiling, drafting big rigs and blowing through stop signs aside, it is pretty safe, I NEVER speed anymore, I'm always in Grandma mode these days as it is all about keeping the ScanGauge happy, and I was quite amused when I saw all the aftermarket handling mods not to mention the supercharged/turboed Yaris's, who'd ever thought! All I know for sure is I got 61 MPG coming down the mountain into town, 51.8 back up, and never got over 50 mph. Good vid!

Originally Posted by HTM Yaris

True CG is right about seat level on the transverse plane ( up , down ), but on the coronal plane ( front, back ) you have basically added 90lbs to the front . The effect of the weight reduction won't come into play until you get to a panic situation . If you ever have to make a quick lane change or a quick lane change with heavy braking you will encounter severe understeer . Also if you change gears on a turn you will encounter oversteer . I mean that the over/under steer will be more pronounced than usual .

Idahotom , check out this vid of me on track . In this vid I have done the exact same weight reduction you described . Pay special attention to 1:03 to 1:08 . That oversteer came from me just releasing the gas while turning . If I had been on stock tires the car would have probably oversteered past the point that I could recover .

http://www.youtube.com/watch?v=UCdCdT972Uk

Try a track day or autox to learn about your car's abilities . You will definately have fun while learning about your handling . Not to mention you will meet some pretty cool people .
Oh if you do decide to do Track/Autox ... your dog will need a helmet

[why?]

For me, oversteer is the desired result. Oversteer in fwd cars is just awesome.

[TLyttle]

Oversteer can have its advantages, but neutral is where one wants to be. Neutral at all speeds is the fastest way from point A to point B. I concur that a tail-happy car is really fun, but too much of a good thing becomes lethal, ie, early Porsches...

[why?]

Originally Posted by TLyttle

Oversteer can have its advantages, but neutral is where one wants to be. Neutral at all speeds is the fastest way from point A to point B. I concur that a tail-happy car is really fun, but too much of a good thing becomes lethal, ie, early Porsches...

Not really interested in the fastest way from point a to point b. Interested in enjoying the drive. If I was interested in speed I would buy a sports car.

[Jason@SportsCar]

Our car is down to 1860lbs... The only thing trying to make it tip over the is sticky Goodyear racing slicks. Lighter is better.

[MUSKOKA800]

A bit extreme. Why not just drive a kart if you don't want creature comforts.
Hmmm... remove the steering wheel and clamp a pair of vicegrips onto the shaft. Save more weight and have a tool handy when in need.

[why?]

Originally Posted by MUSKOKA800

A bit extreme. Why not just drive a kart if you don't want creature comforts.
Hmmm... remove the steering wheel and clamp a pair of vicegrips onto the shaft. Save more weight and have a tool handy when in need.

why drive at all? Why not walk? If you want creature comforts why buy a yaris? Go get a lexus or some other car that actually has them.

Stop being a judgmental moron and realize that everyone else does not want the exact same thing you do.

[Biff]

Originally Posted by why?

why drive at all? Why not walk? If you want creature comforts why buy a yaris? Go get a lexus or some other car that actually has them.

Stop being a judgmental moron and realize that everyone else does not want the exact same thing you do.

right...

[KrazyDawg]

What about replacing the hood, trunk, and side mirrors with carbon fiber? It might not be cost effective to go this route.

[why?]

Originally Posted by KrazyDawg

What about replacing the hood, trunk, and side mirrors with carbon fiber? It might not be cost effective to go this route.

it is definitely on my list of things to do, but as you mentioned, it is not cheap.

eventually, i will get the MI hood, and probably a seibon carbon hatch, unless there is better manufacturers that i don't know about yet.

i can't see the side mirror covers being worth it. I doubt they could possibly save any amount of weight compared to the cost. I'd almost thing titanium exhausts would be a better idea than mirror covers.

[Jason@SportsCar]

Originally Posted by MUSKOKA800

A bit extreme. Why not just drive a kart if you don't want creature comforts.
Hmmm... remove the steering wheel and clamp a pair of vicegrips onto the shaft. Save more weight and have a tool handy when in need.

I think you missed my point... Making the car lighter does not make it more tipsy. Make it lighter and you will have less inertia trying to pull it over. Added bonus, better acceleration, brakes quicker, handling improves as well as using less fuel.

[docB]

Light is might. A lighter car, all other factors equal, will be quicker, better economy, etc...If one can lighten the vehicle in such a manner that the ratio of weight held up by the springs to the unsprung weight stays constant, then the vehicle will still ride "nice". Just gutting the interior can be good. At the Auto-x my Yaris ran in, I found a point where taken out the weight made the car tougher to drive. Over steer got to be an issue. I think you get a great benefit from lighter parts that spin or reciprocate. Lighter wheels and or tires, fly wheel & clutch, connecting rods. But how deep are your pockets?
doc

[Idahotom]

"LIGHT IS MIGHT", I like it!

My own take on adding lightness (?), at least on my Yaris, is also not to spend any money, as much as I'd like to carbon fiber everything, lighter wheels etc. Along with that, I'd rather not do anything that'd effect the resale value. While I admire the people who have the deep pockets to REALLY lighten things up, my focus is on not spending any money and making it lighter.

I've noticed just pushing it around in my shop is SO easy, and I've gotten in the habit of, after raising my shop door (converted hangar door and no remote) I just push it outside, then go back in the shop and close the door, then get in and finally start it, thus saving a minute or so of idling. Nothing like a ScanGauge to show you how idling really cuts into your mileage!

After looking at the aftermarket sway bars, I decided not to get one, too heavy! It is zippy enough on the corners as is, I'll just live with it stock. It's still pretty fun to drive! It might be too much fun with front and rear sway bars........