Weight Reduction - a Comprehensive Guide

[nissanguy_24]

Yes... im just waiting for someone to make a special CF S13 drive shaft or something.. Well anything light really. (talk about bank)

[mranlet]

Originally posted by GRiDRaceTech
MR, you forgot how valuable drivetrain lightening is: every one pound shaved from the rotational bits of the drivetrain is equivalent to shaving 20 pounds off the car.

I didn't forget - I do have lightened flywheel and driveshaft in there.

That's a good rule of thumb though, about 1lb rotating=20lbs dead weight, thanks for the spot . Recuding rotating mass also reduced parasitic power draw, increasing power to the wheels.

SMC - I forget who, but there are some companies that make aluminum drive shafts for S13s. You're looking at around $400 though...

[Craftsman]

Originally posted by mranlet
I didn't forget - I do have lightened flywheel and driveshaft in there.

That's a good rule of thumb though, about 1lb rotating=20lbs dead weight, thanks for the spot . Recuding rotating mass also reduced parasitic power draw, increasing power to the wheels.

SMC - I forget who, but there are some companies that make aluminum drive shafts for S13s. You're looking at around $400 though...

It also depends on where at the rotation... The farther the location from the axis the more equivalent weight is reduced.

Basically, reducing the weight of the rods and pistons is more effective than reducing the weight of the crank. Less inertial momentum.

Anyways, this is same for your tires and rims...

Matt.

[GRiDRaceTech]

Originally posted by nissanguy_24
Yes... im just waiting for someone to make a special CF S13 drive shaft or something.. Well anything light really. (talk about bank)

Aluminum: http://w1.igateway.com/clients1/tc/s...ifunction=form
Carbon: http://members.blackplanet.com/rollcage2/

MR- I know you didn't forget, you just didn't emphasize its importance. (Which I'm sure you meant to do, but you were too busy putting together a great post.)

[krazzyyo]

If you want mad understeer, just removing the front bar will give you that and so much more (but be careful on the street in the rain or you'll kill yourself in a high-speed spin).

would that cause oversteer or understeer?

[ovenmittjustice]

removing the front sway bar would make the vehicle prone to oversteer...

On another note.... for more weight saving options, you could shave your head... you know the pesky hair can weigh alot and getting rid of it can save some precious ounces. Oh, and also wear shorts instead of pants because those weigh less too (infact, if you aren't to shy... just go naked) And do some extra laps at the pool... gets rid of that other "spare tire" (this one is good because it has the added benefit of making it so you will fit in that buddyclub racing bucket you ordered on ebay only to find out it was made for 28" waist midgets)

[AREITU]

Originally posted by ovenmittjustice
removing the front sway bar would make the vehicle prone to oversteer...

On another note.... for more weight saving options, you could shave your head... you know the pesky hair can weigh alot and getting rid of it can save some precious ounces. Oh, and also wear shorts instead of pants because those weigh less too (infact, if you aren't to shy... just go naked) And do some extra laps at the pool... gets rid of that other "spare tire" (this one is good because it has the added benefit of making it so you will fit in that buddyclub racing bucket you ordered on ebay only to find out it was made for 28" waist midgets)

And don't forget to do some speed. You can practice drifting all night and lose weight!

[massive]

Personally I always found that eating a light breakfast and taking a good dump before I ran the 1/4 shaved a good 2.5sec of my time.

[GRiDRaceTech]

This wasn't meant to be the "Sarcastic Weight Reduction- a Comprehensive, yet Sarcastic, Guide." Thus, we've had enough. Only genuine answers from now on, please.

[mranlet]

Thanks.

Although, body weight is a worthwhile point - ever notice that the slow Hondas are the ones driven by big fat guys? They completely ruin the awesome P/W ratio.

[Craftsman]

Originally posted by mranlet
Thanks.

Although, body weight is a worthwhile point - ever notice that the slow Hondas are the ones driven by big fat guys? They completely ruin the awesome P/W ratio.

I noticed that in my Honda...

Matt.

[mechaniac]

I'd like a guide on the adverse effect of weight reduction and suspension/chassis setup.

If you have the time.

[GRiDRaceTech]

Lightening a car excessively without utilizing the height adjustability of coilovers or even aftermarket spring/shock combination will result in a car which looks to be standing on tiptoe. This would obviously be detrimental to handling.

Also, the valving on any aftermarket non-adjustable shocks would be improper for the application, as they are assuming a stock-weight car. An adjustable shock would go quite far in compensating for the weight.

[Craftsman]

Here's some equations for you guys to optimize your setup...

First, you need to know your weights at each corner. Remember that this changes dynamically as you drive your car. Weight transfer happens during acceleration and deceleration (reverse acceleration). It occurs in turns also.

Your wn (natural frequency) is the square root of K (spring constant) / M (mass at each corner).

Your damping constant should be 2 * wn (natural frequency) * m (mass). I'm assuming that the damping ratio is one for critical damping... Remember to watch your units.

The only way to make sure you are at optimum is to put your dampers on a shock dyno.

Again, remember that the mass values change dynamically as you drive. You never want to be under damped as that means your car will bounce, and you do not want your car to be over damped as that means that your car will be too slow to return to the original ride height (slow response).

Enough control sytems from me

[Gingras]

wow that was a good write up on losin the weight