Saving weight

[madmax]

You guys always have a few good suggestions so I figured I would ask the question here.

My latest hobby has become my scion xB. I got it because it was cheap, cute and had great mileage. Lately I've gone on a binge trying to eliminate weight to get better performance and mileage. So far I've removed 178 pounds from it. This paid off by adding 5mpg and becoming fairly quick and powerful feeling.

So far I've removed the rear seating, spare tire and jack, rear wiper motor and arm, rear seat belts and installed super light weight wheels.

Any ideas on what else I can do to save some weight (other than me loosing a few pounds). :)

madmax

[zingo]

Well the no-brainer is speakers and a subwoofer if it has one since magnets can weigh a bit. (But since this is Polk Forum, I would assume you want the tunes...) One thought is that the less gas you have in your car, the lighter it is. If you only ever filled it up half-way, you could save 40lbs. However you could do floor mats and any floor coverings since they tend to be heavy rubber. I feel like you are pretty stripped down though. However, if you really want to spend a weekend in the garage you could remove:
*Air conditioning-not only heavy but lowers gas mileage when in use
*Stock exhaust-will be large, steel, and heavy. Besides the weight, a free flowing exhaust will free-up more engine power and make your engine work less hard to perform the same task.
*Air cleaner assembly-replace all the hoses and boxes with a short ram intake a filter. Not only will it weigh less, but it will free-up more engine power.
Beyond that, I don't know how extreme you want to go but here are a few:
-Carpet
-Interior Panels
-swapping seats and steering wheel for lightweight versions
-electronics

I hope this helps (even if it is a little overboard).

[ESavinon]

lose weight, drive naked. you can shave 7-10 lbs in clothes alone.
shave all body hair. That's another 2 lbs there unless you're hairy then you can deduct another 3 on top of the 2 lbs.
Take a dump before driving. that can shave off anywhere between 5-10 lbs.

[engtaz]

LOL

engtaz

[beardog03]

carbon fiber panels....


oh, and take a dump...you can, from what I hear, pinch off a couple of lb`s real quick !!!

[madmax]

I do have to have a subwoofer. I found a 12" Blaupunct driver which is only a few pounds and used a cardboard tube as the enclosure. The whole thing is only 14 pounds. I found a super light weight amp (an infinity digital amp) which is 5 pounds.

I have a really nice video deck in there now which weighs the same as the stock head unit did but keep looking at my creative labs mp4 player to replace it. The mp4 player has reasonable video and sound but its not quite as good as the deck. Weighs 5 pounds less though. :)

I like the idea of light weight interior panels. The AC will stay for now. I have another car I can't hardly drive in the summer because of no ac, don't want a second one. :)

I have the cheapest walmart floor mats. (The lightest mats I've ever seen, half pound for the set.)

Carbon fiber will be on the list. I wonder if I could make carbon fiber interior panels??

madmax

[shack]

So far I've removed the rear seating, spare tire and jack, rear wiper motor and arm, rear seat belts and installed super light weight wheels.

I hope that extra mpg is worth it when you have to wait 2 hours on the side of the road for a tow truck or a friend when you have that first flat tire. Here in TN there are state operated service vehicles that will assist you (on major highways) or AAA will come if you have their coverage and will CHANGE a tire at no cost...but that assumes there is a spare to change. The cost of one tow probably wipes out any savings. The other stuff is ok....but removing the spare and jack is a bad move IMO.

[madmax]

The other stuff is ok....but removing the spare and jack is a bad move IMO.

OK, so I totally agree with you. However, in the past 25 years I have needed a spare one time. That means I carried around an extra 50 pounds for at least 500,000 miles for pretty much no reason. Remember, it is not under the goal of saving money necessarily but also in gaining performance. Sure, it was nice it was there that one time. I'm living on the edge now baby, expect a flat next week! :D
madmax

[Deadof_knight]

Going Fast and having a big stereo dont go together...... Either GO FAST or GO LOUD either way one or the other trying to do both will break you ...

[shack]

I'm living on the edge now baby

Living life without a net ...right up there with base jumpers, mountain climbers and extreme skiers....:D

[PolkThug]

Max,

I've been down this path.

Free: Drain your wiper fluid reservoir.
$80: Replace your battery with an Odyssey PC680 battery.
$700: Pair of Corbeau seats

You'll get your best gains from getting rid of rotating mass. Upgrade:
flywheel
driveshaft
brake rotors
wheels

Regards,
P-Thuggy



PS: Spare tires and jacks are for wimps.

[madmax]

Going Fast and having a big stereo dont go together...... Either GO FAST or GO LOUD either way one or the other trying to do both will break you ...

Damn it all, you are right. I have a nice system sitting around in boxes but it all weighs too much. Couple of new RF 1100 amps, signal processors, subs, caps, wiring, you name it. Bought them for my last vehicle but never got around to installing. Oh how I'd like to run 2200 watts through some big subs as I'm driving down the street. I estimated about 300 pounds if I went that direction. Keep an eye on the flea market. :D
madmax

[shack]

Screw the weight reduction....Add a cold air induction system, a cat back exhaust system, possibly a header, maybe a performance chip and you can get more performance without sacrificing mpg.

[shack]

Max,

I've been down this path.

You'll get your best gains from getting rid of rotating mass. Upgrade:
flywheel
driveshaft
brake rotors
wheels

Regards,
P-Thuggy

Not too sure that driveshaft upgrade is going to help much.....

[madmax]

Free: Drain your wiper fluid reservoir.
$80: Replace your battery with an Odyssey PC680 battery.
$700: Pair of Corbeau seats

You'll get your best gains from getting rid of rotating mass. Upgrade:
flywheel
driveshaft
brake rotors
wheels


PS: Spare tires and jacks are for wimps.

Consider the fluid reservoir drained, a light weight crank pully ordered and the battery replaced. (Actually, already replaced the battery and forgot to mention. Saved a good 20 pounds!) Also, my rims weigh 7.8 pounds each. ;)

Didn't realize they made light weight rotors, will look into that. The flywheel looks hard to get to for a weekend mechanic but I'll check into it further.

Seats huh? Is safety with the air bag setup any concern if seats are replaced? Safety is where I planned on drawing the line. Also, is there anyplace to find a weight comparison of aftermarket seats, couldn't find any info. Funny that none of the manufacturers give the weights on their websites. Looked at weapon r, sparco and corbeau sites.

Shack, already upgraded with the cai, cat back and header. Actually just wrapped the header with heat tape last night. Itch!

madmax

[PolkThug]

Not too sure that driveshaft upgrade is going to help much.....

Its a huge improvement.

For Example, stock Mustang driveshaft is 40+lbs. Aftermarket driveshaft is 18lbs. It saves 22lbs, but that is not the best part, its 'rotating mass', which makes that 22lbs worth more like 100lbs of regular mass. More of the horsepower that the engine makes will now be transferred to the wheels because you have made the drivetrain more efficient. End result = faster car.

[PolkThug]

Seats huh? Is safety with the air bag setup any concern if seats are replaced? Safety is where I planned on drawing the line. Also, is there anyplace to find a weight comparison of aftermarket seats, couldn't find any info. Funny that none of the manufacturers give the weights on their websites. Looked at weapon r, sparco and corbeau sites.

Corbeau does give out their weights but unfortunately I can't look at car related sites from work to give you a link. I've got Corbeau CR1's and I love the way they "hug" me :o , makes you feel more connected to the car.

Airbags not needed if you have your seatbelt on and it works. Then if you ever get a roll bar you can add a four-point seatbelt.

[shack]

Its a huge improvement.

For Example, stock Mustang driveshaft is 40+lbs. Aftermarket driveshaft is 18lbs. It saves 22lbs, but that is not the best part, its 'rotating mass', which makes that 22lbs worth more like 100lbs of regular mass. More of the horsepower that the engine makes will now be transferred to the wheels because you have made the drivetrain more efficient. End result = faster car.

Since the XB is a FWD there is NO driveshaft....

[PolkThug]

Since the XB is a FWD there is NO driveshaft....

LOL :D

[shack]

Airbags not needed if you have your seatbelt on and it works.

I vote for keeping the airbag....

[PolkThug]

The flywheel looks hard to get to for a weekend mechanic but I'll check into it further.

Fidanza makes one for your car.

[Sami]

Engine fans haven't been mentioned yet? Ok, now they have.

You obviously don't want to go to extremes so save the AC and power windows, there only so much you can save without taking out functional stuff.

[madmax]

You obviously don't want to go to extremes so save the AC and power windows, there only so much you can save without taking out functional stuff.

I'll give up the rear power windows. No seats back there anyway.

Looked but couldn't find that dang driveshaft anywhere. :D

madmax

[Jstas]

It's a Scion xB. It is decidedly not a performance car.

That said, since you are "living on the edge", take off the front and rear bumper covers and remove the metal crush bumpers behind them. Then put the covers back on. You'll drop anywhere from 150-300 pounds depending on the size of the bumper.

Replace rubber bushings with urethane. They are lighter and stiffer and will last much longer while tightening the suspension up. The difference is small but you can save 5 or 6 pounds overall with new end links, control arm bushings and so on. Depends on what you can actually replace.

If you have fog/driving lights, pull them out, you don't need them. That's 5-10 pounds too.

I think it's already been said but if you don't use it, 86' the back seat. That's another 70-120 pounds in most cases. You can pull rear seat belt mechanisms and latches too. That's another 15-20 pounds.

Most of the other stuff that has already been mentioned is good too. However, the performance modifications like exhaust systems and air intake systems can mess with the computer enough that you actually hurt mileage and performance so be careful with what you do there. The flywheel, lighter brakes and even performance shocks and springs can help reduce unsprung weight and driveline weight too. That will make more of a difference than just stripping the car down.

I think that the engine fan is already an electric fan because of the FWD configuration. You could mess with the coolant temp by using a colder thermostat and changing the fan speed but that might trigger the limp-home/save-myself mode again.


A couple of things. safety devices like airbags and seat belts are required by federal law. If you tamper with them, including removing them, you can be subjecto criminal penalties. If you remove the airbags and seatbelts yet retain seats for passengers that those items are meant to protect, your insurance company can prosecute you for fraud.

Emissions are federally protected by law for 80,000 miles. The only way they can be removed or tampered with is if they fail or wear out before 80,000 miles. If you are caught with tampered emissions systems, you can be prosecuted. It is unlikely that you will be prosecuted but all you need is one guy having a bad day. The fines are drastic and penalties even include jail time. If it is an off-road vehicle, you are OK. However, if it is registered and emissions controlled and driven on public roads, you need that equipment.

But again, I'm going to say, it's a Scion xB. If you want a race car, get one don't spend a ton of time and money making a car that is on the level of economic appliance even more uncomfortable than it already is in the name of better performance. You time and money might be better spent elsewhere where these modifications will yeild more drastic results and benefit you in more than just gas mileage.

[Sami]

I agree with Jstas, don't spend much money on modifying your car. :)

[madmax]

But again, I'm going to say, it's a Scion xB. If you want a race car, get one don't spend a ton of time and money making a car that is on the level of economic appliance even more uncomfortable than it already is in the name of better performance.

I already have a race car. I'm looking for as much performance as I can get just because that is how I am. ;)

I wouldn't remove the bumper due to safety but you have me wondering something, could it be a bumper could be made just as strong out of a much lighter material??
madmax

[shack]

I wouldn't remove the bumper due to safety but you have me wondering something, could it be a bumper could be made just as strong out of a much lighter material??
madmax

Yes...but it would be cost prohibitive. Titanium, carbon fiber, etc...

[Polkersince85]

One thing we used to do was jack up the rear. You will always be going downhill. :D


Try ram air scoops down the side to inject a vaccum breaker airflow at the rear of the vehicle.

[ledhed]

I wouldn't worry about a spare tire. The Corvette Z06s simply threw in a roadside assistance kit consisting of a can of fix a flat.

[madmax]

I wouldn't worry about a spare tire. The Corvette Z06s simply threw in a roadside assistance kit consisting of a can of fix a flat.

Awesome idea! Cheap, lightweight, performs close to the same function! I wonder which brand works the best?

Man, I love this car. I've done tons of work on it in only a few hours. Three to be exact. Everything is just a bolt away, easy to deal with and easy to get to.

madmax