Weight reduction question

Hey guys,

Curious as to if anyone has any ideas on how much weight reduction is possible on a 06 legacy gt? I have no plans of doing so, yet I am really curious how what kind of curb weight is achievable.

Thanks in advance!

No idea. IMO kinda defeats the purpose of the LGT. If you want a stripped down car, go with the STi.

No idea. IMO kinda defeats the purpose of the LGT. If you want a stripped down car, go with the STi.

 

 

+1

 

 

the leggy is a comfortable 4 door cruiser......

No idea. IMO kinda defeats the purpose of the LGT. If you want a stripped down car, go with the STi.

 

+1

Yea there's power, but the legacy is more of the Subaru Luxury car.

What would you be willing to remove?

You could strip out all the interior and trunk, and remove all sound deadening.

You could swap to a much smaller battery, run it at 1/4 full gas tank all the time.

 

 

But if you did all this, you'd remind me of all the boy-racer Integra type R geeks that I associated with many years ago that did this. All in the name of another 1/2 second off in the 1/4 mile?

 

Those cars were unbearable to ride in for more than 5 minutes.

There was an article where someone took one of the ricer cars and proceeded to run 1/4 mile. Each run, they took something off. The fastest run of the day was when they got down to the bare chassis with no body panels, drivetrain, driver seat, instrument cluster, and 4 wheels.

 

I'm sure <2500 lbs is achievable if you gut everything on the inside.

Reducing the weight of a car properly ... can be expensive.

 

I would start with trying to reduce unsprung mass. That means lightweight tires and forged rims (17 inch) and replace the steel low control arms with Spec B aluminum arms.

 

From there, you can start replacing all the exhaust components with tubular stainless steel or even titanium components. The stock exhaust manifold is heavy since it includes two heavy cast iron elbows.

 

Replace the stock struts with coilovers. The fixed perch struts are heavy.

 

If you live in an area that doesn't get too cold, you can replace the battery with a Braille all-weather battery. I use one of these batteries and it's started the car at 16F without a problem.

Light weight flywheels and pulleys will help too. Swapping power seats with manual seats will probably save a few pounds. The spare tire and jack are worth additional few pounds. Lastly you can always go on a diet...

Auto transmission is the first to go - way heaver then a manual.

 

I'd take the doors off - they are heavy

You can easily lose 27 lbs off the front brakes and have much better breaking to boot with an AP BBK.

 

You could also get better breaking (not as good as the 330mm rotors) if you went with iONs slightly smaller 4 pot AP kit that loses about 33 lbs).

Go on a diet and start dating Kate Moss.

There was an article where someone took one of the ricer cars and proceeded to run 1/4 mile. Each run, they took something off. The fastest run of the day was when they got down to the bare chassis with no body panels, drivetrain, driver seat, instrument cluster, and 4 wheels.

 

I'm sure <2500 lbs is achievable if you gut everything on the inside.

 

I remember that article. This kid wanted to get a sub 14 second car out of his Nissan Sentra, so they just stripped it down to basically nothing like you said but the left little donut wheels on the back and normal wheels up front. Pretty funny picture with the driver in a full racing suit and helmet sitting on what amounted to a stripped go-kart.

 

Eric

also cutting the bumper beams and slap on the jdm bumpers too :/

run with no carpet... racing steering wheel with no airbag, gut the trunk, no rear headrest.. not much there but i guess it helps everyone else got it covered

bulemia is the fasterest?

you can get the car down to 2900 lbs without going to a tube-frame chassis .. but that's asking a lot of work such as replacing all the sheet metal to carbon fiber parts and dropping the car down to a race-prep state before a cage is put in.. the car starts off around 3500 lbs.. start gutting.

No idea. IMO kinda defeats the purpose of the LGT. If you want a stripped down car, go with the STi.

 

Lotus Elise!

you can get the car down to 2900 lbs without going to a tube-frame chassis .. but that's asking a lot of work such as replacing all the sheet metal to carbon fiber parts and dropping the car down to a race-prep state before a cage is put in.. the car starts off around 3500 lbs.. start gutting.

 

Thank you Keefe for answering the question instead of telling me how insulting the idea is of doing this to a legacy. If you read my question you would have read that I have no plans to do this but I was interested in knowing what is achievable. Of course I wouldn't want to takeout those beautiful seats

 

So 2900lbs with the stock body. Anyone agree? Disagree?

you can get the car down to 2900 lbs without going to a tube-frame chassis .. but that's asking a lot of work such as replacing all the sheet metal to carbon fiber parts and dropping the car down to a race-prep state before a cage is put in.. the car starts off around 3500 lbs.. start gutting.

 

 

Sure, this all can be done but at what cost? Is that fact that it's a Legacy at that point absolutely critical?

 

If you want a light-weight stripped out track racer, why not just find an old Civic EG, strip that down to nothing, plop in a tuned K-series, slap in some great suspension bits and call it a day.

 

You'll have a 200+ HP car that weighs, what? 2200 lbs?

 

If a turbo AWD car is a must (ie: Subaru) then why not just start out with a lighter WRX, or even a GC? No?

 

 

I'm confused...

 

It makes as much sense as stripping a GS430 Lexus in order to get more performance out of it... why would you buy a car like that, or a Legacy GT and proceed to take away it's luxury/ comfort factor?

It is an excellent question and should really be given alot of thought and discussion. The legacy gt is a relatively light car with a lower torque turbo motor that I suspect will respond dramatically to weight loss.

 

Yes it can be very expensive but nowhere will you get a better bang for your buck in overall performance.

 

The lower weight of a legacy gt iswhy I like the car. Even with cars with similar power to weight ratios that are heavier, you can "feel" the extra weight in the vehicles dynamics and polar moment of intertia.

 

If someone hasnt already noticed this. Put 200 more lbs in your car and drive it. The legacy is such a nicely balanced car with a smaller turbo motor that you will instantly feel this weight.

 

Since you are not monkeying with engine, electronics etc.... This sounds like a very reliable way to achieve improved performance AND improved fuel economy.

 

Please keep this thread going. I will be glad to implement many of the changes that arent beyond my technical ability.

 

The lower aluminum spec b control arm, what do they weigh? What do the coil over weigh?

 

Sam

I looked up the braille batter and it looks like the lightest "reasonable" size battery is 11.5 lbs. Does anyone know how much the stock battery weighs?

 

Sam

If you want a light-weight stripped out track racer, why not just find an old Civic EG, strip that down to nothing, plop in a tuned K-series, slap in some great suspension bits and call it a day.

 

I'm confused...

 

It makes as much sense as stripping a GS430 Lexus in order to get more performance out of it... why would you buy a car like that, or a Legacy GT and proceed to take away it's luxury/ comfort factor?

 

Again, this is just a theoretical question. No one is planning on ripping apart a legacy to be street racer.

Sure, this all can be done but at what cost? Is that fact that it's a Legacy at that point absolutely critical?

 

If you want a light-weight stripped out track racer, why not just find an old Civic EG, strip that down to nothing, plop in a tuned K-series, slap in some great suspension bits and call it a day.

 

You'll have a 200+ HP car that weighs, what? 2200 lbs?

 

If a turbo AWD car is a must (ie: Subaru) then why not just start out with a lighter WRX, or even a GC? No?

 

 

I'm confused...

 

It makes as much sense as stripping a GS430 Lexus in order to get more performance out of it... why would you buy a car like that, or a Legacy GT and proceed to take away it's luxury/ comfort factor?

 

 

The question that everyone missed was "how low can you go with a Legacy GT?"

 

 

 

 

 

 

As for your Civic EG, they can go down to 1800 lbs with a cage.. they will fluxuate with a driver which can round out to 2000 lbs +/-.

 

This discussion wasn't about racing.. more so of "what if the car didnt have all the 'luxuries' or better yet "what does the actual functional chassis weigh?"

 

Remember, this was just a question for curiousity reasons, he has no intentions of racing it.

 

Let's take a step back, forget racing, how about saving the weight for the fact of saving gas from standing starts of stop and go traffic and better yet, making parts last longer such as brakes, suspension and tires?

If someone hasnt already noticed this. Put 200 more lbs in your car and drive it. The legacy is such a nicely balanced car with a smaller turbo motor that you will instantly feel this weight.

 

Since you are not monkeying with engine, electronics etc.... This sounds like a very reliable way to achieve improved performance AND improved fuel economy.

 

Please keep this thread going. I will be glad to implement many of the changes that arent beyond my technical ability.

 

The lower aluminum spec b control arm, what do they weigh? What do the coil over weigh?

 

Sam

 

 

1) weight management is an issue for car manufacturers. There's a certain standpoint where comparing weight to power ratios doesnt demonstrate the true justice over a long race or long periods of time of use. Sure, there's more power to move the added weight, but that's a lot of "unnecessary" energy (remember Newton's laws everyone).

 

2) IMO, the GT is heavy.. driving a 99 GC8 at 2700 lbs @ 130 whp vs. 05 LGT at 3400 lbs @ 200 whp is a world of a difference. I'll drive the GC8 any day due to the 700 lbs difference.. that's like carrying 4 other passengers.

 

3) Spec B arms are about 40% lighter than the steel arms from what I remembered.. I think the last time I checked you would be saving around 12 lbs for each one.

 

4) Depending on the coilovers, it will vary. For my Zeals, I saved about 6 lbs up front for each corner and 4 lbs in the rear, resulting a 20 lbs loss.

 

5) I dropped out my stock catback and added a short catback straight pipe to meet race rules. I saved another 45 lbs there (55 lbs vs 10 lbs of pipe)

 

6) I had Racing Brake rotors for street and AutoX use. I saved 5 lbs per each front corner resulting another 10 lbs loss

 

7) I swapped tires and rims from the stock ~45 lbs down to my street setup rims and tires of 34 lbs, resulting another 44 lbs total loss.

 

8) My next strip-down will be the battery. I believe the stock battery is around 45 lbs.. a Racing battery (either Oddessey or Brialle) is around 8 lbs or 12.5 lbs, resulting another 30+ lbs loss.

 

9) The spare tire, jack and all are around another 45 lbs.. I normally dont carry my spare unless it's for long trips as I replaced my spare with a bottle of fix-a-flat and my commute to work and home is short (10 miles one way). I have plenty of tires at home to switch to if I need to swap out a bad tire.

 

10) I normally drive with a half tank as much as possible. 1 gallon of fuel is around 7.5 lbs at sea level. Running around with 7 gallons is another 50 lbs in the car that you dont really need if your commutes are short.. this is also good practice to keep yourself from driving so hard. The less you drive hard, the better your fuel economy will be.

 

11) I never carry anything in the car, I leave it very clean and empty to keep the weight to the minimum. I never leave my bowling ball or golf clubs in the trunk. Everything is out of the car unless I need it for that day.

 

Noticed that all my mods are still have the full interior fully intact.

Starting with an 05 unlimited helps at 3300 pounds. Going from the prior post:

 

I'd say 2950-3000 pounds is reachable with bolt-ons if you don't mind the car loud and not emissions legal, along hoping you don't get a flat. All figures pulled from my butt:

 

-130 pounds exhaust system

Replace cast iron exhaust manifold joints, exhaust piping, mufflers, heat shields, cats with coated ss or titanium piping. If replacing catback with straight pipe saved 45 pounds, I gotta think three cats, heat shields, and the cast iron chunks in the manifold are worth another 85.

 

-44 pounds

Go for lightweight 17" wheels and tires

 

-30 pounds brakes

Go for lighter brakes (didn't somebody mention 25-33 pounds worth of savings from the fronts alone?) Be conservative and go for all four.

 

-30 pounds

lighweight battery and tiedown

 

-45 pounds

spare tire and jack

 

-24 pounds

alum front arms

 

-20 pounds

coilovers