Nitrosobmw

i would go coilovers, gt3 seats or racing seats, smaller lightweight wheels, carbon fiber roof panel, carbon front hood, momo steering wheel, all interior carpeting delete, and i would leave the rest alone.
i did remove the rear spoiler's accordion thing, and i removed the bumperettes and filled the holes and it looks much much better.

i always run my car with a little more than 1/4 of gas, took out the spare tire, rear seats,rear seat belts, change the rear engine carpet for the gt3 lighter weight carpet, didnt do it for weight savings at first, just to have the carpet with the gt3 logo on it, and when i compared both the gt3 was at least 1 pound lighter.

my 2cents, hope that someone would benefit from this,

6ta1

thanks, always appreciate feedback

of course unsprung (and more importantly rotational) weight would have more impact.

the wheels are not necessarily the bigger issue - the RG5s are among the lightest 19" wheels available, should be something like 18 lb front and 20-21 lb back.

the brakes are where the overkill is - those front discs are probably not much heavier than stock (alu hats) but the weight is a lot further from the center of the hub which makes it a lot worse.

I have been trying to sell those mammoth brakes for a while.
Until I sell them, I can't fit anything lower than 19" for the wheels.

While we are talking about rotational mass, I've skipped the idea of lightweight flywheel for now as it seems that single mass is not very streetable from what I read.

One thing I have been looking at is titanium fasteners (for the wheels and driveshafts), trying to figure out if it's safe or not.

Last, please keep in mind that my goal is not to build the lightest 996 out there.
My goal is to have a lighter full spec / full interior 996, that looks stock to the untrained eye
(rear seat delete actually make the rear seat more usable for short distances, lol!)

So far the only thing people notice is the rear bumperette delete (still trying to find a nicer looking solution) and the mods have not been a constraint driving all year round as a semi daily.

alpine003

Engine mounts and pulley are slightly lighter than stock, right?

Did you actually go by weight when shopping for stereo components?

A big weight savings would also be the seats. I'm not sure if you've already swapped those out.

FRP or CF deck lid as well.

Forgot if you had at least the rear gt3 bar but that is pretty light as well.

Cup car halogen headlights are noticeably lighter than Xenon.

You running stock cats?

halik

This is exactly what I'm talking about. Every single person* I've seen going nuts about weight by drilling stuff out or taking off safety equipment has oversized wheels on the car. Dump the 19s, get some 17s (you have narrow body) and save 5-7 lbs per wheel. Taking off bumper rebars or drilling plastic pieces before doing that is just asinine, imo.

Rotors won't make as much difference, the center mass is closer to the axis of rotation.

*I've seen like 5 threads on various boards about this.

Edit: Doh, just re-read this, you have 19s to fit the brembos in the front. I retract my comments.

alpine003

Halik, also the 19's he has is actually lighter or close to the lightest 18" OEM alloy combo available depending on what tires he's running. Even most forged 18's aren't that much lighter than the 19 Champion RG-5's.

But I see what you're saying. I too see a lot of stupidity amongst enthusiasts. The other pet peeve I have(mainly the VW/Audi crowd) are the ones running $4k wheels but using Federal or Nankyang tires or some $hit like that.

At least 6ta1 isn't running 4 12" subs in the back. lol

Dennis C

I tend to agree with Halik on both points - wheel size/diameter and thread incoherence.

The Champion RG-5 is a very good lightweight wheel. To me, the bigger issue is the increased gyroscopic stabilization force generated by the larger wheel. Larger diameter wheels have more mass further from the center of rotation than smaller diameter wheels. This creates additional stress on suspension and brake components. It's not a significant issue unless the car is used on the track or driven very hard on the street. For me personally, I'd take the smaller diameter wheel with the associated weight savings and decrease in stress on the car.

That being said, the list of modifications to decrease weight is pretty impressive!

alpine003

As OP said and Halik later noticed, it's really a moot point as the brake system that OP is running will not let him run 18's. 19" Champion RG-5's are the best that can be done from that standpoint.

6ta1

yes, there is an overall "pad" section of pluses and minuses. Like I have a very, very light (like less than .5 lb) home made battery bracket that I am not counting.

Need to go weight the car and see what is the actual total is now

Yes. And I probably have the lightest head unit on the market (half din, no cd player, has SD card and USB instead). For the speakers I wanted neodymium magnets but I ended up giving up as I could not find any at a decent price.

Where I got crazy was that since I had a bose amp but did not want to cut the stock harness I ordered an aftermarket harness from UK. When it came in I decided it was too heavy (.75 lb), so I modified it down to I think .2 lb (before and after pictures attached).

Someone local has Rottec seats for sale... a bit high for my budget but definitely considering


are you talking about the bumper bar? if so I don't have one in the back anymore, kept the front one mainly for towing purposes if ever needed

never thought about this... good idea indeed


yes, don't want to mess too much with this but might have to if I run ROW tune


As someone pointed out, it's a fun project to me even though I am getting somewhat OCD on some aspects. And for the most part it was free!

6ta1

bottom line, I should really get rid of those brakes.

But they do look super mean - the car is very sexy from the profile view

philooo

keep in mind that removing the front tire impact the crash worthiness of the car. they engineered the front crash test with the spare in place if i recall well.

nice to see that you track each weight saving precisely, good thread for the rest of us.

what about the secondary air pump ? this must be the most heavy piece in the engine bay that you can remove. they sell plates to close off the engine opening, but nobody documented this mod yet.

Dennis C

I understand and I agree in this case. I was just making a general point about wheel size.

alpine003

In regards to that, yes I think we're along the same lines but even more importantly when it comes to the 996 chassis, quite a few "pro" drivers tested the 996 with a 18" vs 19" wheel option and they ultimately went faster around the track on 18's as it was more stable and confidence inspiring. So even if the combo weight(tire + wheel) is the same between both setups, the stiffer and less forgiving sidewall on the 19's could prove to be less stable around the track if you are capable of even driving remotely close to 10/10ths.

Cruisers need not apply and can run 20's for all I care.

redridge

get rid of the carpet... its heavy.

alpine003

I have my carpet out now but plan to put it back in. You'll want to leave it in if you plan on driving it at least 75% on the street and wanna listen to the radio and have some level of civility on the inside.

I'll see if I can weigh it this weekend.

6ta1

Update on the car:

I have now added Gt3 seats in carbon fiber as well as weighed again some parts to confirm that the car has lost a total of > 288lbs.

I just did a GT3 alignment today (possible on stock 996 control arms, by the way), and the car handles like a go-kart.

weight
manuals ------------------- 3
spare wheel & tools ----- 31
cd changer ------------- 5
center console delete --- 3
lower console ----- 0.9
front coil covers & filter --- 4.2
lightweight battery -----32.9
battery tray ----- 2.2
door speakers ----- ------ 5
door airbags ---------- 5
dash speakers --------- 2.6
bose amp ------------- 3.5
lightweight headunit -- 2
front deflector ------- 8.5
front bumper bar ------- 1.8
alarm horn -------- 0.7
GT3 seat - driver -------- 32.4
GT3 seat - passenger 31.2
front total --- 174.9

weight
rear wiper ----------- 4
rear seat ------------ 22.5
rear bumper bar ---- 18.8
subwoofer ------ 14
rear seat belts ----- 5.4
rear interior insulation 4.5
rear speakers ------- 2.6
rear exhaust tips ------ 4.5
engine lid ---- 5.6
exhaust tips ------ 3.6
exhaust -------------- 22.8
tail lights ------- -2.4
cat heat shield ---- 2.8
exhaust heat shield out 2
exhaust heat shield in 1.6
rear bumperettes 1.2
rear total ---- 113.5