Need Dieting Advice...

[Wayne 962]

Yo! I'm going to place a small section on weight reduction in the Performance Section of the new book. I think it's somewhat relevant to at least mention it as an alternative to expensive engine modifications.

So, what do you recommend for weight savings? Not really my area of expertise, although I am aware of the obvious:

- A/C Systems
- Windows/doors
- Lexan windscreens
- Sunroof removal
- Fiberglass hoods & fenders
- Lighter rotational mass (wheels)
- Interior stuff ripped out.

Anything else?

-Wayne

[Nader]

This guy's site is referred to as the gold standard for weight-weenies:

http://early911sregistry.org/jCalzia.html

[Bill Douglas]

Underseal removed, light weight seats...

[Don Plumley]

Kurt posted this link: http://sportcompactcarweb.com/features/0208_scared/ - 39% weight reduction should be some sort of gold standard.

Back on point: spare tire, tools, jack (just carry a 0.1 oz AAA card); hood/trunk shocks, sound pad in engine compartment...

Also the driver...I weigh just under 155 dripping wet, I'm guessing there's a 50-100 lb advantage over the average dude...finally some benefit from being a little guy!

[APKhaos]

Wayne,
This is a classic in my book - I think is should be attributed to Randy Webb.

Principles of the Church of Light [Weight]

1. The worst weight is unsprung weight.

2. The next worst weight is the highest weight (weight at the top of the roof -- the highest above the roll centers of the car).

3. The next worst weight is the weight at the rear of the car (because it is already tail heavy).

4. The least worst weight is the weight at the front of the car.

5. Losing weight may not be as important as having the center of pressure coincide with the center of gravity.

6. Clapton is god. Colin Chapman is god. Dr. Ing is god.

7. Worship magnesium and keep it holy.

8. Verily, I say unto you, titanium will make your heart sing like the birds of the field.

9. Thou shalt not use carbon fiber in stessed applications.

10. Cain slew Abel because Abel put fake carbon instrument panel surrounds and Ti cupholders on Cain's car.

[racemor]

Doesn't Randy or someone use a smaller (lawnmower?) battery in their race car? That would help some. Of course a couple of AAA Duracells would be even better .

Tom

[Jim Richards]

weight distribution considerations?

[Chuck Moreland]

Since I'm in the midst of putting my own project car on a diet, I've been studying this and have real-world results too.

Check this thread:

Project Elephant, How much does it weigh?

The big low-hanging-fruit items are:

Battery - Up to 45 lbs
Rear seat sound pad and seat backs - 40 lbs
Racing shells - Up to 50 lbs
Spare tire, jack, tool kit - Up to 40 lbs

Fiberglass can save a lot of weight (especially on the bumper cars), but is much more involved and expensive.

[racemor]

I forgot about this one. I saw this at the PCA race at VIR on Jim Thomasson's early 911 racer. He had deleted the heavy turn light unit just using the lens and an exposed bulb. Probably not the best idea for the street but an interesting idea, see photo:

[Joeaksa]

Wayne,

How about the two worse offenders, and ugliest addition I know of to the 911 body? Take the damm new style bumpers off of the front and rear of the 74-89 cars and retro back to RS or early style bodywork?

This would get rid of both the massive bumpers and take loads of weight off of the car where it hurts the most, behind the motor!

Joe

[island911]

Don (&Kurt) that says it;

Weight saving for a 911 needs to be in context of useage (track or street).
I would say divide the section into two groups (track and street).
street easy ones:
- remove spare, et al (as mentioned)
- A/C System (easy choice in some areas)
- Minimize the stereo system (speakers are tonage)
- Lighter rotational mass (wheels if you don't have fuchs)
- Interior stuff minimized. (aftermarket floormats can be heavy)

track easy ones:
-start with an old roller (galvanized bodies add 22lbs +lack of rust)
-strip as picture above; use carbon fiber, glass and PC (Lexan) to make aero.

[widebody911]

How about a more relevant, rear-engined application?



and then



We just kept cutting more and more metal off of it...

[Sarah]

Need dieting advice??

Salt = water retention
Sugar = fat
Consume both in moderation

Oh...sorry....wrong type of diet!! Couldn't resist!!

[jpachard]

I think that muffler is one too, plus you get more Hp to boot. Removing the front spare is not such a good idea. Our local region requires them to be in the car for DE events. Besides the safety factor; 1. you are removing weight from the front. 2. I hate being caught without a spare. Just a thought.

Cheers, James

[Langers]

Ok I drew up this list for my Citroen so some things may not be applicable. Having said that it seems to be fairly comprehensive:

*Remove normal seats
*Remove back seats
*Remove Air Con
*Remove door inners
*Remove window mechanisms
*Remove windows, replace with polycarbonate (Lexan)
*Remove Radio + Speakers
*Remove sound deadening of any kind
*Remove carpet
*Remove seatbelts
*Remove foglights
*Remove airbags
*Remove sun visors
*Remove tool kit
*Remove spare wheel
*Remove windscreen washer bottle
*Magnesium Wheels
*Lightened Flywheel
*Remove Roof lining
*Simplify Wiring Loom
*Remove alternator
*Lightweight battery (enough capacity to last one race)
*Drilled brakes
*Fibreglass body panels
*Remove power mirrors

[pbs911]

I just picked up 78SC Targa from a CB/alignment after a recent diet and received the new weight. Here is what I changed:

F/G hood
F/G front and rear bumper caps
Remove all A/C components except for blower in smugglers box
After market seats for a savings of about 10 lbs each
RS door panels
Deleated rear seat backs
No spare or tool kit
backdate heater system to pre-74
cross-drilled rotors
wiper resevoir
gas overflow resevoir
air pump

Added weight:
Autopower 4 point race roll bar
2 - 6 point Schroth harnesses
heavier 89 OEM sway bars
Carrera oil cooler
Fiske FM-10 17" wheels and wider tires for the Fuchs

The car weighed in today at 2520 with a 1/2 tank of gas . So I met my goal of breaking the into the 2400 lb. category if you consider the weight with a dry gas tank. A great improvement over the factory specs of 2750+ for a stripped down SC Targa.

[Joeaksa]

Paul,

How much did you feel the difference with all that weight off of the car? I keep hearing that even 100 pounds make a difference and more than that is really noticeable.

Joe

[silverc4s]

I think it was at Spa this year, we saw Juan Pablo Montoya remove his WRISTWATCH and hand it to a member of his pit crew before heading out on a qualifying run!!!
Attention to detail, like Porsche deleting one sun visor, and the glove compartment door on RS lightweights....etc.

[CamB]

Think about how much less peppy the car feels with a passenger... and the other benefit is less weight improves braking and cornering.

Wayne - I think its a good idea for a section but you should consider ordering it in ease of implementation and/or "streetability".

Lexan windows is getting a bit extreme.

And you would need a caveat about how many of these changes make the car less civilised. But more fun!

[Wayne 962]

Cool, more than enough for at least a small section.

Let's not forget that F=ma. F being the force produced by your engine, M being the mass (or weight for laymen) of your car.

If you remove 300 lbs from a 3000 lbs car with a 200 HP engine, it will be the equivalent of adding an extra 20 HP. In other words, a 10% reduction in weight is equivalent to a 10% increase in HP. This is of course, a very general description, but it also corresponds with what you feel 'seat of the pants'-wise as well...

-Wayne