Weight Reduction

[mrebusa]

I have read through and I don't feel like sifting through old threads to see what people are doing. I have a 14' 1LE and I feel like it is a brick house. What are you guys doing to drop some weight off this thing. I am heavily debating trading it in on a veto, but if I can get this thing down a few pounds and justify adding power to it, it may be worth keeping. I love the look and handling of the car, hence why I haven't swapped to a Z06 already.

If I drop the wheels for something lighter and the seats that should save me a sizable amount. What about brakes? Anything else I can take out of the car?

Thanks guys.

[PapaKlutch]

There are a bunch of threads, but it would be nice if there was a weight loss chart! lol.

It seems like wheels, tires, brakes and battery are pretty good spots to start.

I think it's X25 that has a 1LE thread with weights of various brake systems.

[mrebusa]

Appreciate it, I wish there was a chart too specifying where the major weight loss components are and what options we have to get this pig on a diet.

[Andoskyy]

Originally Posted by mrebusa

I have read through and I don't feel like sifting through old threads to see what people are doing. I have a 14' 1LE and I feel like it is a brick house. What are you guys doing to drop some weight off this thing. I am heavily debating trading it in on a veto, but if I can get this thing down a few pounds and justify adding power to it, it may be worth keeping. I love the look and handling of the car, hence why I haven't swapped to a Z06 already.

If I drop the wheels for something lighter and the seats that should save me a sizable amount. What about brakes? Anything else I can take out of the car?

Thanks guys.

I believe you can shed up to 40lbs with an aftermarket catback, probably even more after headers.

[ForcFed93]

Get some two piece racingbrake rotors front and rear. You'll shave 20+ pounds but because it's unsprung rotating mass it'll make the car feel lighter in everything you do.

Not all weight loss is created equal.

[Andoskyy]

Originally Posted by ForcFed93

Get some two piece racingbrake rotors front and rear. You'll shave 20+ pounds but because it's unsprung rotating mass it'll make the car feel lighter in everything you do.

Not all weight loss is created equal.

Damn, $2,300 for 4 rotors and pads!?

[ForcFed93]

Originally Posted by Andoskyy

Damn, $2,300 for 4 rotors and pads!?

Yeah, not cheap. I bought a used set for cheap and put them on my old 2005 CTS-V years ago and I was shocked at how much better the car felt in everything. Cornering, braking, accelerating, it didn't matter. The car felt noticeably lighter and more nimble.

[NVR2L8]

Originally Posted by ForcFed93

Get some two piece racingbrake rotors front and rear. You'll shave 20+ pounds but because it's unsprung rotating mass it'll make the car feel lighter in everything you do.

Not all weight loss is created equal.

Bingo! Reducing the rotating mass is the place to start. First realize that the larger the diameter, and the faster the revolutions, the more weight is reduced:

1. Tires and wheels. Each lb. reduction = 4 lbs. lighter
2. Brake rotors. Each lb. = 3 lbs.
3. Aluminum flywheel. Each lb. = 2.5 lbs.
4. Lighter weight drive shaft (alum/CF). Each lb. = 2 lbs.

* numbers are approximate, but the logic is sound.

Then go to static weight:

1. Replacing seats (electric) can save 80 lbs.
2. Braille or other battery can save 20 lbs.
3. Remove rear seat, about 20 lbs.
4. Remove carpet from trunk.
5. Remove windshield washers, tank, and motors, 25-30 lbs.
6. Remove excess stereo, especially if you have a big sub woofer in the trunk.
7. Start replacing any iron/steel parts with chromoly, 30-35% less weight.
8. Remove air conditioning motor, vents and lines. 20 lbs.
9. Lighter weight exhaust can save up to 40 lbs.
10. Lighter weight radiator, not sure about weight savings.
11. Go on a diet! Lose 40-50 lbs.

[Pushrod Pete]

anyone here have those RB rotors? I remember reading about someone having issues with them on the track. maybe cracking? don't remember exactly what the problem was.

[X25]

Originally Posted by SteveZ28

There are a bunch of threads, but it would be nice if there was a weight loss chart! lol.

It seems like wheels, tires, brakes and battery are pretty good spots to start.

I think it's X25 that has a 1LE thread with weights of various brake systems.

I bookmark important information in my journal at the very first page, so I can refer to it when I forget the details.

From my build thread:

Originally Posted by X25

Current mods list (will keep this post up to date. Last update: 1/17/16)
Legend: Planned | Procured | Installed

• Engine / Powertrain
  • TSP 304 LT Headers with custom 3" X Pipe (TSP's own x-pipe did not fit perfect). 20, 76
  • Improved Racing oil pan baffle.
  • DEI coil boots.
  • 2000 degrees F matte-gray header coating. 20
  • Diablosport Intune w/ custom tune from FSP - $489 shipped.
  • DeWitts radiator - $575 shipped. 12, 30
  • Improved Racing oil cooler with Setrab Series 6 / 48 rows. how-to, 39, 314, 335, 343, 472
  • Improved Racing oil sensor manifold (ENV-150).
  • Tick remote clutch bleeder. 460, 477
  • Detroit Truetrac 912A686 Helical differential - $511 after rebate. 403
  • Z/28 rear differential cooler (23216684) - $530 + shipping (use coupon code to get 5% off total). 415, 477
• Interior
  • OEM Recaro seats. 214(manual), 227, 268(powered)
  • Custom harness bar with tank plates. 435, 499
  • Schroth Racing Profi II ASM. 435
  • Auto Meter 5286 Direct-fit Gauge Pod. 135
  • Auto Meter 6348 Oil Temp Gauge. 135
  • Auto Meter 6327 Oil Pressure Gauge. 135
  • Auto Meter 9114 Dimmer For LED Gauges.
  • SRP pedals. 577
• Handling
  • Z/28 suspension package . $3449 shipped. 58, 104
    
    • Front/Rear DSSV struts,
    • Front/Rear sway bars with end links ,
    • Front control arms,
    • Rear upper and lower arms.
  • Z/28 full aero. 181, 182, 285
  • ZL1Addons see-through wicker bill. 367
  • Pegasus CNC
    • Solid subframe bushings. 545
    • Delrin (solid) rear trailing arm bushings at the knuckle. 545
    • Camber plates. 545
  • Tires
    • Hankook Ventus R-S3 305/30/19 for daily driving. 89, 137
    • Pirelli Trofeo R 305/30/19. 179
    • Michelin Pilot Sport Cup 2 305/30/19. 193, 204
  • Wheels
    • APEX ARC-8 19"x10.5" +22 spin forged wheels for daily driving / rain. 56, 89, 130, 137
    • OEM Z/28 Wheels 19"x11" +11 fronts, 19"x11.5" +26 rears. 184, 204
• Brakes
  • Quantum - Competition Brake Cooling Kit - $239.95. how-to
    • NACA ducts: $20.
  • StopTech ST60 Front BBK 15” red (83.193.6800.71). 114, 121
  • Stock rear rotor (92245929) - $85.31 shipped x2.
  • Pads
    • Raybestos ST47 R2600.18 Front pads for StopTech ST60 caliper. 121
    • Cobalt Friction XR2 Rear (CRB-XR2-D592-15.0MM-R).
• Fluids
  • Engine oil: Mobil1 5W-30.
  • Differential oil: Redline 75W-90NS (no friction modifier for helical Eaton TrueTrac diff).
  • Transmission oil: Amsoil Signature Series Multi-Vehicle Synthetic ATF.
  • Brake fluid: Motul RBF 600.
  • Coolant: GM DexCool @30%.
  • Suspension grease: Amsoil Synthetic Polymeric Truck, Chassis and Equipment Grease, NLGI #2.
• Other
  • HSA elimination - $80 shipped.
  • Wheel comparison: 48, 117.
    
  • Brake systems/comparison: 58, 79, 93, 117.
  • Dyno: 155.
  • Alignment: 560.
  • TPMS valve-stem issue: 582.
  • 305/30/19 XL tire weights 619.

Originally Posted by X25

......
Brake systems weight analysis:
I got StopTech weights directly from them:
ST-60 Caliper w/ Typical Bracket & Pads
Caliper: 34/36/38x32 8.786
Pads: 63-400-0060 (2 Pads) 2.884
Bracket: 36-330-8615 1.398
Total 13.068 lbs

380x32mm AeroRotor w/ Typical Hat & Hardware 17.450
Typical 380mm Hat & Hardware 3.750
Total 21.200
Grand total for this 15" system is 34.268 lbs.

In comparison, stock caliper is about 12 lbs with pads. However, stock rotor is 25.15 lbs. The total is about 37.15 lbs.

I do not know the weight of stock CTS-V caliper, but it's substantially bigger than the stock. My guess would be at least about 14 lbs. The two piece ZL1 rotors are about 27.5 lbs, bringing the r total to about 41.5 lbs.

So there you have it, the monster 15" StopTech system is only marginally lighter than the stock system, yet it's almost 7.5 lbs per wheel lighter than the comparable OEM (CTS-V) 15" system. CTS-V brakes cost so much less, though, so I might still pull the trigger one day Wilwoods weigh similar to StopTechs, but only with 14.25" diameter.

Originally Posted by X25

Yep, I actually owned a similar ST60 StopTech BBK before for my Corvette Z06, and they worked very well on that car. The bridge sometimes gets stuck a bit as far as I've heard, but I never had that issue. My issue was rather the extreme tightness of the pad slots. I had to use a rubber hammer to insert the pads the first time. I asked about it to StopTech, and they said the slot guides relax a bit in time, so they make it extra-tight to compensate: fine.


Yeah, 15" is huge, especially considering these are iron! The StopTech pads are also smaller, in turn allowing the ring to be narrower, further saving weight. 21.2lbs for 15" rotors vs. 27.5 lbs for 14.6" ZL1 rotors or 25.1 lbs for stock 14" SS rotors look pretty good. Considering Z/28 suspension was tuned with lower unsprung weight than SS, every bit counts.

So far compared to SS and Z/28:

• Front brakes: -3lbs over SS, +2lbs over Z/28(?)
  • StopTech: 21.2lbs rotors + 13 lbs calipers
  • SS: 25.1lbs rotors + 12 lbs calipers
  • Z/28: 17lbs(?) rotors + 15lbs(?) calipers
• Wheels: -3lbs fronts / -4lbs rears over SS 1LE, -2lbs fronts / -3lbs rears over Z/28.
  • Forgestar: 24lbs front and rear(?)
  • APEX: 23lbs front and rear
  • SS 1LE: ~28lbs front and ~29lbs rear(?)
  • Z/28: ~26lbs front and ~27lbs rear(?) EDIT: I later measured both front/rear at 26.2 lbs.
• Tires: -4lbs over SS 1LE, -1lbs over Z/28 (if I choose to go with R7s).
  • Hoosier R7 315/30/19: 27lbs
  • Hankook RS3 305/30/19: 32lbs
  • SS 1LE G:2 285/35/20: 31lbs
  • Z/28 Trofeo R 305/30/19: 28lbs

Originally Posted by X25

For those interested (info from StopTech directly):

• Stock rears: ~32 lbs.
  • SS rear stock rotors: 24lbs each.
  • Calipers including pads: 8 lbs each.
• StopTech ST41 2-piece 355mm rotors and ST41 caliper: ~30.1 lbs.
  • 355x32mm AeroRotor w/ Typical RearHat & Hardware: 19.048 lbs.
    • AeroRotor 15.548 lbs
    • Typical 355mm Rear Hat & Hardware 3.5 lbs.
  • ST-41 Caliper (32mm Wide) w/ Typical Bracket & Pads: 11.044 lbs.
    • Caliper: 7.524
    • Bracket: (w/ Studs, Nuts , Washers) 1.302
    • Pads: 2.218

[Centerforce_Clutches]

Rotational and sprung weight changes will make a huge difference, as mentioned above. Theres quite a bit to be shed, without having to lose your interior and street car luxuries. Look into forged wheels, lightweight suspension, clutch/flywheel, and exhaust. It doesnt seem like it, but just doing basic things like that can save the equivalent of a few hundred pounds!