Weight Reduction (budget diet) for daily/spirited driving
 

It's your car, so by all means go for it, but I don't think the change in weight will be particularly noticeable on the street. And when you consider that you'll get increased cabin noise, lose the back seats, have no spare, louder exhaust (which might get you in trouble with the law), and have non-adjustable seats, I just don't know if it's worth it tbh

A full muffler delete will be awfully loud, and I really don't think it's worth the tradeoff (especially given that you don't track/autox the car).

Thats a good point. I understand the cabin noise will inevitably increase, but I don't think it will be horrible - especially since my music is up a decent level most of the time. The Sparco R100's say they can adjust, maybe you had another set in mind? Or maybe I am wrong that they can?

I appreciate your feedback and opinion - I was also wondering, you honestly think that the added horsepower from the OFT (+30hp give or take), complimented with 130 subtracted pounds will be un-noticeable?

The muffler delete is already installed. I got it last week. It is honestly not that loud - especially when I pay attention to which RPM I am staying in. It has the potential to be very loud, of course, but the driver has control of the level - at least that is how it is for me.

I have a quiet exhaust and driving with the seat down is more than noticeable.

@campy hypothetically, with the shredded (http://www.dumbbell-exercises.com/im...-exercises.gif) weight, it would be like driving with 75.6% less of my own body weight sitting in the car. I imagine that reduced weight, met with adequate wHP increase, has to feel noticeable (even on backroads?) - then again I wouldn't know yet lol

@boredom.is.me I think that can be solved with a super light-weight symmetrical board (w/e light-weight material) to replace the 'rear seat backing (15 lbs)' - perhaps you could also add some sound proofing to make sure the sound is contained in the trunk rather than the entire cabin.

That kind of weight reduction will only show up on a stopwatch at the dragstrip or autoX or road course, and only with a consistent driver. You will NEVER notice the change in performance on the street. Enjoy the car, forget about spending time/money/effort and making the car more of a PITA for a performance change you won't be able to feel.

No point in doing all that removal. Also, you are modifying the sprung weight of the car. That's what is keeping the car planted to the ground when you are going bumps, potholes, etc. If you want to lower the weight, its best done through the suspension and wheels which are unsprung weight.

@Bach415 - So in order for weight reduction to work you must first lower the car, but using coilovers or springs? And only a light weight wheel works? Why not the OEM set? Although I know each are 41s lbs. I guess shaving 10-15lbs off each wheel/tire adds up nicely :o

Also, is it a decent option to go with Koni's and some eibach sportlines or teins? or is that weaaaaaaak

Stop eating.

You'll save money and weigh less. It's a win/win situation.

185 lbs @ 6'2" ... I'd rather not weigh less and look like a rod. D:

Cool thread, worthy of other's input.

Mine is that your budget is more robust than mine. I'd have a hard time justifying $450 for a Super B battery when I can save 20 lbs. vs. OEM for $150 with a Braille (Amazon).

Good point haha. I overlooked the price of the battery I listed. I didn't realize it was that expensive. Ill change that - thanks!

Well, 1086, like they say back on the farm, it's your tractor.

(I just made that up ....;))

I will admit that you have identified some interesting ways to reduce the weight of the car.

However, I agree with @campy and your "car's diet" doesn't seem to go along with your driving objective:

" I am a casual daily driver and on the weekend I enjoy spirited driving in the mountains/back roads/hills, etc. like I am sure many of you.".

Personally, I don't notice much difference in driving around the back roads, byways and in the mountains, whether mrs humfrz is along or not ...... and she weighs in at a bit more that 138lbs.....;)

I would think that proper tires and honed driving skills would net you more "comfortable" driving fun, than stripping the car.

humfrz

Might as well lose the stock wheels while you're at it.

Get something like RPF1s, which are 5-6 lbs lighter than stock...in turn translate to an ever further weight loss because rotational mass is exponential.

If we're going to discuss rotational mass then also look into a carbon driveshaft and a brake kit. :)

I'd suggest you start with the tune first and see how you like the feel of the car, then you can move on to weight reduction.

I used to daily an older Porsche with a roll cage, coilovers, aftermarket exhaust, racing seats, and some of the insulation/carpeting taken out to reduce weight (and make space for the cage). It's cool at first, but it definitely makes the car more tiring to drive. With the FRS, I can go on a 300 mile trip and feel good at the end of it. In that Porsche, after 15 minutes I would have a headache and backache.

Also, girls hated how loud and uncomfortable it was :lol:


Of course, this is just my $0.02. You may like it, but in my personal experience, I'd prefer all the comforts that come with a less-modded car for a DD. That said, don't let strangers on the internet make your decisions for you! haha

I bought a road bike for a grand, going to loose 40-50 pounds off the car with it. Pretty good value :)

Agree with everyone above.

Find some lighter wheels.

Keep your sound deadening and upholstery.

Do an intake, exhaust and a tune if you still feel that it's lacking.

don't lie you never have girls in your car

Bought a mt bike for 4, gained 30lb plus another 30+ for the rack to carry it in car! And gain weight from the increase in calorie intake, aw hell, no matter, I enjoy it!

Here's another weight reducer, delete stereo, speakers, and wiring. Free. Dump water from the windshield squirter. Run with only two gals of gas in tank. With your estimates, this will now get you easily below 2600. Heck the gas alone will drop more than 50 lbs, more than any single item listed!
Just don't blame us when you're out in the boonies, stuck in a ditch, windshield covered in mud, tire blown, cold because engine doesn't run from no gas, and listening to the wind whistling through the trees.

You don't need to lower the car. Lowering the car only affects the handling of the car, not the weight reduction. Replacing coilovers maybe a lighter yet stronger solution in terms of reduction weight as well as maintaining and modifying handling. You can still use oem wheels and tires but those are the easiest way to remove unsprung weight assuming you have a good wheel tire combo(aka light rims not on super meaty tires)

For those two options, I have no opinion on them. You may be better off asking someone who is good with suspension as I have no experience running them on the car.

Think about it this way, in order for weight reduction to actually work, you have to have a good balance between unsprung and sprung weight. Too much or too little of one or another may have an effect on your control of the car as well as how planted the car will be towards the ground..

Hey man we went on 2 dates so I'm gonna count that as dating.

Who needs girls when you have cars anyways.

You should see @Anthony 's if you want to see a car on a diet:lol:

I search for weight reduction as you. But you must be carefull to have the same balance ratio. Look at seibon carbon for doors , hood and trunk ! It will cost but it could be effective!

DO IT. I see most people are against the idea, but I half-gutted (everything behind the front seats) my DD and loved it so much, I started to consider taking the stereo and A/C out too. That would be a terrible idea living on the Gulf Coast, so I just bought an FR-S and gutted that. Then I un-gutted my DD. Here are some points to consider:

- I drove around over a year with my only car gutted and enjoyed it enough to do as I said with the FR-S.

- If you take your time and stay organized, you can put everything back in whenever you want. Those stupid plastic pushpins tend to snap, but you can also buy more. Just take your time and take them out gently. You can even buy tools specifically designed to take them out. I just used screw drivers and out of the 200 or so (it seems) I've taken out, I feel like I only broke ~10. Also, take pictures if you think you might forget where things go.

- If you care about maximizing performance and not much else, dropping weight is the best $:Benefit thing you can do. Most of it is free. You can always keep it comfortable and still boost performance by buying performance parts and not stripping the inside. But you will not be absolutely maximizing performance. For most people, that's ok, but I get bothered by only giving it 90%. 100% or GTFO.

- The car will become way noisier on the inside, which is either a love or hate thing. Personally, I love it. I can hear the road going by under the car. It increases the sensation of speed, and I feel more connected to both the car and road. It's more motorcycle-esque.

I went with a Shorai LFX21L6-BS12 off of Amazon for like $176. 3 pounds, 1 ounce. 5 year warranty.

http://www.ft86club.com/forums/attac...1&d=1386721296

It's true. Still have quite a way to go too!

Now that's impressive. What battery tender/minder do you use? Any issues in use like heat from the car's high current charging system?

Interesting to read your findings with you weight reduction efforts.. Weight is the enemy.. I'm enjoying having a lighter weight car with less power, vs a powerful car with more weight.. But I'm not sure I would be up for the extra NVH for everyday life.. How much weight have you shed so far? Have you gained an appreciable amount of performance for the weight you dropped so far.. Thanks for the info.. Great stuff you won't find in the rags..

Part of me has always wanted to yank the doors and drive around like a Jeep Wrangler. With a rollcage of course...

Like others have said the unsprung weight wont make as much of a difference. Get some light wheels (17 x 8 rpf1s with 225/45 would save some good weight) along with lighter brakes (either a bbk or 4 pot subaru calipers or just lighter rotors)

Headers are another good place to drop some weight in terms of exhaust, so getting lower weight & HP is win-win.

Oh, my ......:sigh:

While weight reduction is an interesting topic, ...... if I wanted a small, fun car, that didn't have a "back seat" or a spare tire and was 250# lighter, I would have bought (kept) this car .... ;)

humfrz

Yup. Im still thinking of getting one as me and the gf are sharing one car right now (and we both work), so that means i drop her off/pick her up.

I was all about weight when I first started on this forum and read too many autox builds. I mean Im looking at weights when I am upgrading, but its cost-benefit. If I can manage to shed some lbs great, but i really do have a budget. Lol

I bought the Shorai one. I have yet to use it or install the battery, so still no clue on performance/questionable-ness of such a tiny battery.

I'm not done. I scrambled to get as much done as I could for a car meet, and since it has passed, I've been spending more time with friends and family. I just got back from a 6 month deployment. But I roughly estimate I've shed ~185 pounds. It seems to be noticeable. Nothing drastic, of course, but I haven't had the opportunity to really push the car yet. It definitely looks real tough though, if anything.

For me as a DD I'll probably do a

lightweight battery
rear seat delete
header back but keep stock muffler
Remove spare and tools unless going on a trip

My goals with my car is keep it looking stock (-ish, besides wheels maybe some springs) and not be obnoxious to drive.

@Anthony

The way you described it is basically how I WANT the car to be- especially "I can hear the road going by under the car." - that is dope haha + you lost roughly 185 lbs, more dope! Thanks for the battery recommendation too!

@bestwheelbase can you do that? haha that would be fun, even just to try for the weekend. So many heads would turn haha

@humfrz I mean yeah, that is true, but the FRS just looks way sexier. I have respect for the miata and love the car for what it is, but if I were to ever get one it would be as a side car that I romp around with while not giving two sh*ts and I would very much want it to look like and (in my dreams) have the same components as below haha! (greedy face)

https://scontent-b-sjc.xx.fbcdn.net/...63277224_n.jpg

Here's my weight loss list. It's mild, but I want the car to pass the Girlfriend test, and I'll be getting performance elsewhere too.

Weight loss:

Removed OEM Spare Tire - 26 lbs
Removed OEM Trunk tools - 6 lbs
Removed Owner's Manual - 3 lbs
Removed washer fluid (1 gallon) - 8lbs
Net loss = 43 lbs

OEM Battery - 30 lbs
Braille battery - 11 lbs
Net loss = 19 lbs

OEM Catback - 39 lbs
HKS Hi Power catback -22lbs
Net loss = 17 lbs

Stock headers - 21 lbs
JDL header -13 lbs
Net loss = 8 lbs

Over pipes & front pipes
Net loss = 2 lbs (estimated)

Total Net Weight Loss = 78 lbs

Edit: just got my car corner weighted. Total weight with 180lbs of driver and half a tank of fuel is 1279.5 kg or 2820.8 lbs. So mch for armchair calculations!

:P

As far as weight reduction goes I like to try and balance it, meaning that I like to take weight off the front to equal whatever I remove elsewhere. Whenerver I don't lose weight I at least try to gain performance without adding weoght but it's a bit of a tradeoff.

I added 18 inch OZ ultraleggeras and michelin PS2s. They weight about the same as the stock 17s net but get a LOT more grip out of them.

I also added RS*R coilovers and an Alcon BBK. No idea what the actual weight savings is over stock but they've increased my car's handling and braking capabilities immensely.

Then there's power to weight:

Stock dyno baseline power = 161.5 whp
Tuned dyno power = 189.5 whp
Net power increase = 28 whp

Guesstimated crank hp = 226 ish?

This is an interesting post! To keep the car reliable, good looking and pass the wife or girlfriend test is a challenge, a challenge. I want to increase the acceleration of my vehicle also, as it is 100% stock. From my personal experience some of the easiest and reliable ways is of course lose weight, which many people gave quality data and specs. I agree a tune is simple and can add power! A tune works...! Also, what I would like to do, as I don't drive faster that 75-80 in this, street car (maybe one day autocross) is to change the gear ratio. I have seen some gear sets for sale, I think their was a 4.56 to 4.67 ratio set out there. Gears can make the car accelerate faster at different speeds. I would like to see what 4:56 to 4.67 gears in my automatic with a tune would feel like with the spare out and a 1/8 or 1/4 tank of gas. If I had a manual I would research light weight flywheels and the carbon fiber or light weight drive shafts (rotational mass). I think these two things can make a difference you could feel and have measurable data.

Another way of "changing the gear ratio" would be the tire size. Though this isn't "orthodox" you could go to a 16" wheel, say a Motegi, lose 4-5lbs on the rim and then also lose the tire height, the stock tire is 24.7" and some of the 16" tires are 23.5" for a 215/45/16 or a 215/40/16 will weigh 19lbs (1lb lighter than the stock michelin and 3lbs lighter than the stock Bridgestone) have a tire height of 22.7". These are just a few ideas, as I know there are many ways to move, these are just my thoughts. This in combination with the gear change and tune would have my interest indeed!


Staying with a light weight aftermarket wheel either 16x7 or 17x7 can save 20lbs of unsprung rotational mass. (watch the tire weight also..)


A Light weight flywheel can save 10lbs and a light weight carbon fiber driveshaft is about 10-12lbs savings also.


A total savings of 40lbs. "They" say this can be some of the best weight you can lose.

Losing weight is not hard to do, but how to lose weight and maintain (or even improve) the practicality of the car for daily driving?

How about light weight anti-roll bars?

I think all US models come with 18mm solid bar in the front and 13mm solid bar in the rear. Cusco offers a 16mm solid bar for the front and a 14mm hollow bar for the rear. Cusco said its light weight bars are just a stiff as OEM ones and I agree.

That should reduce weight by another 2, 3 lb.

Or lug-nuts?

I use Muteki open-ended lug nuts for my Enkei RPF1's. The Muteki nuts only weigh 25g each, vs about 70g for the OEM nuts. Nearly 0.5lb (of unsprung weight) saved per wheel.

Or light-weight pulleys

A set of (5) light weight pulleys can save about 5lb.

My wife drives the FT-86 to work daily. I changed the pulleys without telling her (she thought I was just going to change oil and the anti-roll bars.)

Then she jumped up and down for almost a week asking what I did to her car. I finally told her. Then she told me the car felt so much faster and she was wondering what I did.

You could always drive around with a half tank of gas... A gallon of gas weighs ~6 lbs so that's close to a 40lb reduction in weight.