Enlightenment

[mjshira]

this is a great thread. I don't have the knowledge (yet) to contribute but I am glad to see it here. for my two cents, I think it's key that if the car is to be used on a public road any reduction in lbs not risk safety.

[RWebb]

and that is why I have not put an erp front suspension on my car...

[Jeff Alton]

I run the ERP front end, I don't street drive much but what do you think is the safety risk?

Cheers

[Whtnkls911]

Does anyone know who makes plexiglass rear windows and rear quarter windows that use the factory seal?

Thanks,
John

[RWebb]

Originally Posted by Jeff Alton

I run the ERP front end, I don't street drive much but what do you think is the safety risk?

Cheers

Don't know really. I talked about it with C.E. and he seemed to indicate it might be OK, but he wasn't sure.

I'm concerned about how strong it would be in an accident - say if you hit a boulder or stump on the roadside or debris in the road...

[911pcars]

Originally Posted by RWebb

Don't know really. I talked about it with C.E. and he seemed to indicate it might be OK, but he wasn't sure.

I'm concerned about how strong it would be in an accident - say if you hit a boulder or stump on the roadside or debris in the road...

Any component in the steering system that isn't at least as strong as an OEM part shouldn't be used. If the ERP part is approved for racing, it should be okay for normal street conditions, but that claim should come from ERP.

However, many manufacturers sell products for "racing applications only" or words to that effect in order to avoid having to go through the DOT certification process and/or because DOT-specs don't apply; e.g. non-oem engine management controls, racing tires, headers, plastic windows, harness restraints (?), etc.

Sherwood

[afterburn 549]

I use the factory seal

[RWebb]

Sherwood - I agree. The erp parts are technically for racing only.

Since I tear the F. suspension off the car every 8 years, there will undoubtedly be a future opportunity to do that (unless I pull a Paul -- sell the 911, and start thinking about Z cars or some such...).

[RWebb]

Lamborghini has introduced a lightwt. version of the Gallardo, the
Superleggara, which is 220 lb. lighter than the "cheap" regular
version.

Body:
- essentially the same as the regular Gallardo, which uses an all Al
space frame, but some CF reinforcements were added
- numerous Al components were replaced by CF components
- side windows are now plastic, not glass

Interior:
- all Al trim was replaced by CF components
- cloth is all Alcantera (does this save wt.??)

No mention of anything else done to save that 220 lb.

from R&T, May 2009, p. 21


some of you may enjoy this tidbit:

http://www.aa.washington.edu/research/structures/pubs/IJVD%20feraboli%20lambo.pdf

[SCWDP911]

just reviving a great and interesting thread to read.

[ej911]

You can get a kit from me to put a 256hp/247ft-lb torque Subaru EZ36D engine in it, that will save you close to 200lbs.! That is if you do not mind improving the weight distribution.

[RWebb]

Hey Shaun - here are some more tidbits to ponder (or save up for)...



- from the May 2009 issue of Rod & Truck







this unit body weighs 531 lbs. - that is about 110 lbs. LESS than the considerably more flexible old 911 unit body

[RWebb]

R&T Feb. 2012 reports on p. 14-15 that for the 2012 SL (R231), Benz has introduced a largely Al body - the A pillars are and windshield header are steel, the rest is Al (extruded door sills, hydroformed rails, lots of different thickness sheets, and the firewall and suspension towers are cast Al).

The body in white weighs only 560 lb., so compare with the post above. The 560 lbs. for an SL550 is a wt. savings of 275 from the current 550, and torsional rigidity is increased by 20%.

Sounds like it would be good for AutoX if you can get a bear to rip all the luxo-crap stuff out of the interior.

Meanwhile, isn't the new 991 still nearly all steel? Several different types of steel?

[James Brown]

running some weight to hp programs, a 2000 lb car needs 320 hp for a 11 second 1/4 mile run. that is a good starting point for a light car with some heavy parts in the right places (cheaper). so mostly CF or fiberglass parts on a striped tub, 340 hp 3.6 w/carbs (lightest intake system?), good brakes, cage, racing stuff +- 2000 lbs=very fast 1200 lb on the rear 800 on the front

[RWebb]

GM has a new technology to thermoform body panels from Mg - until now they had to be die-cast and were thicker, hence heavier. These will be 33% lighter than Al.


GM Moves Toward Production Magnesium Body Panels

- the fruits of the new fuel efficiency standards will be harvested to make beter sports cars...

[RWebb]

R&T Oct.?? 2012 issue (p. 62) reports that Lamborghini's Aventador has a 505 lb. unit body (that's for a body in white; the passenger cell is 325 lb.) that is incredibly stiff - 35,000 N-m per degree. It is made of CF.

The only stiffer car I am aware of is the Veyron -- except for F-1 cars that is...

[RWebb]

Like Janus, let’s turn our faces from the future (briefly) and take a look back in time. Back to 1962 to celebrate the Lotus Elan, a car that was the ultimate in light weight design, and designed by a genius. This design turns 50 this year.

[RWebb]

1962 was a banner year for sports cars: we also got the MGB, the Ferrari GTO, the AC Cobra (soon to be Shelbyized), and the Jaguar E-type had just been launched a year earlier. What would prove to be the world’s most versatile sports car was still in development. At Porsche, the 911 was still a collection of ideas, drawings, plasticine, and plaster. Aichle, PORSCHE 911 – FOREVER YOUNG, p. 31-39.

But the Elan was a car ahead of its time. It was technically innovative with four-wheel independent suspension, the first backbone tube chassis of any road car, and a fiberglass body. The Elan also came with 4 wheel disc brakes, foam-filled safety bumpers, and IRS. Nothing came close to that list of features. And at about 1,500 lbs., the Elan weighed 500 less than the MGB, its closest competitor.

[RWebb]

One key to the light wt. was the compact dimensions of the vehicle. While nowhere near as small as a Sprite, there was not a lot of superfluous body anywhere.

The outline views show the packaging advantages of an upright inline engine – note that the motor is not even inclined like in the BMW 2002, yet there is plenty of space for an A-arm suspension. No need for a McPherson strut with its variable geometry problems. But in the rear, there does not look to be much width for luggage.

[RWebb]

The Elan was “one of the quickest, best-handling production cars money could buy” at that time. And, it was “relatively quiet and comfortable.” R&T, Dec. 2012, p. 70.







Peter Egan recalls his first drive in an Elan in the mid-1970’s as the car having “wonderful” steering and handling. R&T, Dec. 2012, p. 68.


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