Removing weight for better handling and performance

[FPerron]

I've reached the point with 310 wheel HP, where I can't add more power without upgrading drivetrain components. Consequently, I'd like to remove weight as an alternative.

 

Obvious ways to lose weight are to replace the seats and install a lightweight battery in the trunk.

 

How about the front bumper beam? How much does it weigh, and can it be removed or replaced with a lighter structure? Is it important for the stability of the suspension?

[JoeFromPA]

Did you remove your spare and tools already? Easy to just add a portable sealing and inflation kit. The lightweight battery is a good idea for weight savings and transfer of weight, but remember that the extra cabling adds weight when transferring it back to the front end.

 

There are some good "weighs" to cut weight from your exhaust system, I'd look into that a bit (though maybe you've already gone down that road).

 

Removing trunk liners/carpeting and stuff can shave a few pounds.

 

Cobb Hollow Sways save ~3 pounds over stock

 

Lastly....and honestly....removing rotating mass is your best way to gain tangible "butt dyno" effects from weight removal. Pick up the shortest set of wheels/tires that will fit over your brakes and meet your day to day needs. If you can go with 17" wheels with a slightly shorter sidewall, and the wheels are 5-6 pounds less than your current, and your tires are the same or a few pounds less per tire, you will definitely feel it. The wheel/tires allow you to make it a "shorter" gear by reducing the tire sidewall weight, and then reducing the weight of that gear will give you some dramatic difference in low-end acceleration feel. It'll also feel great everytime you turn, transition, or brake.

 

Joe

[FPerron]

Yes, I've removed everything that's not bolted down and am running 17" Rota Torques (which is all I can afford).

 

I'm mostly interested in the issue of removing or replacing bumper beams. Any input?

[JoeFromPA]

My understanding is that they are there to prevent major damage from a minor hit. I don't think it's a problem to remove them (IIRC, there are a fair number of people running without them due to other modifications)....just that it's the major thing standing between the outside world and your radiator/ ac system. Let alone the other stuff

 

Joe

[FPerron]

Any idea how much the bumper beam weighs?

[Spec B]

Front bumper beam wieghs about 35-40lbs, maybe less. I am going off of memory when i removed mine for the FMIC install. - I never actually wieghted it on a scale.

[whitetiger]

It all depends on how crazy you want to get with weight reduction. seat replacements can reduce weight. remove the back seats and get aftermarket seats for the front. If you dont care about A/C, you can remover the condensor, compressor and lines for weight savings. get a light weight racing battery and put it in the trunk too.

[FPerron]

Front bumper beam wieghs about 35-40lbs, maybe less. I am going off of memory when i removed mine for the FMIC install. - I never actually wieghted it on a scale.

 

 

Thanks

[Spec B]

BTW you could get reletively significant savings in wieght by swapping shocks and springs with coilovers. i was shocked, but I would say I saved about 40-45 (EDIT, I thought this through a little more and was shown cold hard facts, savings is closer to 25-30lbs) lbs by swapping those out.

 

Other ideas (that will not effect comfort):

 

 

- Switch over to a single exhaust, not sure how much you will save, but it will shed a few lbs.

- Remove all the heatshilds around the DP for 2 or 3 lbs abd just add a cobb heatshieild to help with underhood temps

- Lightwieght pulleys, will reduce rotating mass and real lbs.

- Lightened flywheel (same as above)

- Remove fogs

- Remove underbody tray

- Remove engine cover

- Run your winshield washer fluid near empty all the time.

[JoeFromPA]

Holy snike! Coilovers reduce weight that much? How the heck do they accomplish that?

 

Flywheel is a great way to substantially reduce rotating mass...not sure if you already did a clutch upgrade, but running that power you will eventually. If you don't mind the side effects of a lightened flywheel, you can really lose alot of rotating mass.

 

The underbody tray is probably 2-3 pounds and would negatively effect you at speed....

 

That bumper beam weighs 35-40 pounds? Wow, I guess with coilovers, a lightweight exhaust, removed bumper beam and spare and tools, lightweight battery in the trunk...you could probably shave 150-200 pounds from this thing without too much headache and while moving the weight distribution rearward substantially.

 

I didn't realize.

[Spec B]

Coilovers are much smaller and lighter.. Also, not sure it the spec b bilstein set-up is heavier than the stock LGT suspension. Al I know is when I threw the stock setup in the box to take to the buyer, I had trouble lifting them, they were probably 85-95 lbs all together. The coils were 40-50lbs all togther...maybe I embellished a little bit in my post, probably about 40-45lbs saving.

[Napping]

Removing front bumper beam not safe, but if performance that important, then might as well remove side impact beams too and install roll cage instead, then carbon fiber hood, panels, fenders, perspex windows. And for extreme, wear lightweight clothes, and go on diet.

[LittleBlueGT]

I put on KW2 coil-overs, and yes I saved weight, but not 40 lbs. Sheesh!

 

I bet you weighed the coil-overs w/o top-hats, and the stock ones w/ or some small error like that.

 

Here is my coil-over thread:

 

Another coil-over Review ............by LBGT!

 

I saved 9 lbs for each in the front, and 1.5 lbs for each in the rear.

 

That is about 21 lbs total. I can't imagine other coil-overs being lighter, unless they used extremely thin CF or something like that. FWIW the Cusco ones I had looked at were a good pound or two heavier then the KWs each.

[Spec B]

I need to work out...maybe it was only 20lbs!

 

I got the BC racing coilovers, the box that was delivered with the coilovers said I think 45lbs...and I could lift it easily.

 

After the install I threw the stock setup in the same box (it barely fit) and I could barely lift it (really)..it had to be at least 80-85lbs.

 

I never wieghed any of it..but I am thinking maybe the bils are heavier that the LGT struts? And i think you reuse your stock tophats with the KW's, the BC racing uses pillowmounts (not sure if that makes them heavier or lighter though)

[LittleBlueGT]

I need to work out...maybe it was only 20lbs!

 

I got the BC racing coilovers, the box that was delivered with the coilovers said I think 45lbs...and I could lift it easily.

 

After the install I threw the stock setup in the same box (it barely fit) and I could barely lift it (really)..it had to be at least 80-85lbs.

 

I never wieghed any of it..but I am thinking maybe the bils are heavier that the LGT struts? And i think you reuse your stock tophats with the KW's, the BC racing uses pillowmounts (not sure if that makes them heavier or lighter though)

 

Bilsteins may be a bit heavier, possibly 4 or 5 lbs total there.

 

OEM top-hats should also weigh a bit more, so maybe 2 or 3 pounds there (total again).

 

So maybe, just maybe you could lose almost 30 lbs due to coil-overs.

[Buru]

- I would guess that coilovers would drop some weight. ~30lbs

- What about rear adjustable lateral links for toe and camber ~6lbs

- Def keep the battery in the front but go to a light weight one (cable

weight is expensive)~10lbs

- The front/rear bumper beam are AL and i would leave for safety.

- Take out the sunroof glass and motor system and replace with CF ~20lbs plus it is up high

- Take out the auto dim mirror with homelink ~3lbs

- I bet the stock seats are crazzzy heavy (airbags, heated, full electric)

you could swap race seats in for when you race and normal ones for

Daily Drive, that is my plan. ~80lbs

- Also BBK's stoptecks will drop some weight. ~25lbs

- Lower your fluid levels ~20lbs

- 1/4tank of gas ~72lbs

- 20lbs off of my gut ~20lbs

- Spare tire stuff and tools ~35lbs

- Take out rear center seatbelts (no one ever sits there) ~10lbs

This is what i plan to do eventually

3500lbs Spec B - 393lbs (not in cluding my gut ) = 3107

that weighs less than my Vette, but not for long.

 

I am sure you could shave some more, but lets get these ideas out in the open.

I would really like to have a weight thread

ie: people weigh stock stuff and modified stuff and post it with a picture, not speculation but reality!!!

 

Side note:

Old girlfriend 155lbs

New girlfriend 125lbs

I just shaved 30lbs

 

Also this will help with mpg's!!!

[JoeFromPA]

My friend, you gained more with that transition than just a loss of 30 pounds

[FPerron]

Thanks for all the good ideas.

 

One reason for running a lightweight battery in the trunk is that I could cable it in series with the stock battery. That way, when I remove the stock battery for the track, I don't have to reload the base MAP.

[Spec B]

Thanks for all the good ideas.

 

One reason for running a lightweight battery in the trunk is that I could cable it in series with the stock battery. That way, when I remove the stock battery for the track, I don't have to reload the base MAP.

 

You only need to reload the real time map if you pull the battery.

[FPerron]

Are you absolutely sure of that? I hope it's true. BTW, I'm running a pro-tune from Mike (formerly of TDC).

[rao]

It is 100% true.

[rexster]

why do you think you'll have powertrain issues with > 310 whp? 4EAT??? removing air bags and bumper beams on a daily driven car is less than wise. and the can of fix a flat wouldn't fix my last blown tire (hole in the sidewall). i would think adding power would be much easier and safer...

[FPerron]

This car is used on the street and for track events. I'm not planning to drive around on the street without a spare:lol:

 

Also, I guarantee that if I swapped an FP Green for my 40bb, my clutch would vaporize in about 5 laps.

http://www.henstoothdiscs.com/images/PictureCar.jpg

[FPerron]

One more thing. My Perrin TMIC must weigh three times what the stock unit weighs. Does anyone make a lighter high performance TMIC?

[Gary Bechtold]

I think there is only the AVO and Perrin TMIC's for the Legacy GT. I want to get one of them someday.