looking for tricks to lighten chassis & components?

jwerion · 09-19-2004, 01:42 PM

I am trying to find additional ways to cut out more non strutural wt. out of my track car. I have cut out the rear seat area, removed all the glass, removed some metal from the dash before covering with carbon, carbon body work, etc. What other areas can I grind on or cut out/off. What components can be lightened or replaced? Any Ideas are welcome Thanks.

Grady Clay · 09-19-2004, 02:11 PM

jwerion,

There are lots of things that can be lightened or replaced with light weight components. Do some searching on Pelican and you will find most of them.

The trap many fall into is the plethora of cool stuff you can add to a 911. A true lightweight has very few extra components. Anything you leave off is lighter.

Best,
Grady

cgarr · cgarr's Garage

What about the Driver??

cg

Grady Clay · 09-19-2004, 02:59 PM

cg,

Yes, the driver is a major component.
Every time I go to the track some (many) try and get my lame 195# driving their 911. I will do that when I get back close to my 145# race weight. Medical issues are a PITA. For now I’ll passenger instruct.

Yesterday I went to an SCCA Solo 2 event for a few hours. I got several drivers good times without my going on track and I had fun.

Best,
Grady

Randy Webb · 09-19-2004, 03:23 PM

Yes, and search on jim + calzia - he doesn't post here but did a careful analysis of wt. savings in getting his car down -- you'll find links to his web page tables and articles in Excl. My name will be in the threads but calzia will get you there.

911pcars · 09-19-2004, 03:46 PM

Randy, slight correction. Jim's comprehensive weight data is here:

http://www.early911sregistry.org/jCalzia.html

Excellence didn't include this valuable information when they published his article in the May, 2001 issue (oversight or ??). Subsequently, he submitted the info to the Early 911S Registry for display and review for all to see.

Sherwood

Randy Webb · 09-19-2004, 04:39 PM

Thanks. No it was not an oversight. When I contacted them, they said they didn't have enough space. This was before you guys (Early 911S) posted Jim's data -- I wrote them 'cuz the text of the article implied there was more info but I couldn't find it.

If anybody wants to get into the real nitty gritty after doing the searches, I have some Email exchanges with Jim (A petrologist BTW - and he used accurate scales to wiegh things). Also have some additional data in my own little database.

TWO things to observe when lightening the car:
1. The cost per lb. to lighten something
2. The effect of the wt. loss on vehicle dynamics --
a. you want to think in terms of 3 axes thru the car. Best places are the roof, the rear, etc. as those are furthest from the car's CG
b. whether the wt. is sprung or unsprung
c. whether the wt. is reciprocating (pistons...)
d. whether the wt. is rotating (flywheel, clutch, CV's etc.)

* If anybody does do a big search for the various threads on this, it would be a public service to compile them all in a thread with links.

Oh - one other thing -- there is thread with (I think) Grady Clay and me on it re building a light wt. 911 engine.

widebody911 · widebody911's Garage

Quote:

Originally posted by jwerion
I am trying to find additional ways to cut out more non strutural wt. out of my track car.

What year is the car?

tctnd · 09-19-2004, 06:19 PM

Well, you might try an old motorcycle trick....To quote my buddy George, "The only practical way to lighten a Harley is to get a skinnier girlfriend".

jwerion · 09-20-2004, 07:44 AM

Thanks for the information I will start searching the web right away and to answer widebody911 the project started as a 78 euro sc non sunroof coupe. I know the narrow bodies are lighter but I did not want to deal with any rust issues.

Ove · 09-20-2004, 11:50 AM

jwerion,

There is a very nice lightweight 911 in the September 2004 issue of 911 & Porsche World. The owner started with a "Mystery shell" which had been lightened before he bought it. Lots of lightening holes, including the inner and outer sills! He claims that RUF made similar holes in their cars.
You can also see that the top of the dashboard has been removed and some other parts of it has been cut off.

Drilling is a good way to remove weight, especially if you make a flange around the hole to maintain the structural strength.

widebody911 · widebody911's Garage

There's lot of weight-loss opportunities on the later cars. For a track car with aftermarket bumpers, you can lose the original bumper mounts and supports. There is also extra reinforcement in the trunk (at least on US-spec cars) that can be trimmed to taste: there's a double wall with a cavity underneath all along the fender bolt line back to the cowl.