Weight of 308 frame?

I am curious if anyone knows about how much the bare frame of a 308 weighs? I was tossing around some numbers the other night, thinking about how much more powerful the 308 was than most other cars of its time (compare to 911's for example) and wondering why the sucker is so darned heavy? It's such a tiny little car, why does it weigh 3,200 freakin' pounds? (or whatever it is, I don't want to argue over the specific weight)

Then I thought, how much weight is tied up in that massive steel frame, and how much lighter could you make the car if it was rebuilt on a hand-made light weight aluminum frame, an exact copy of the stock frame?

No, I have neither the skill nor the money to actually undertake this task, it is a purely theoretical exercise, but interesting to consider.

Birdman

 

Maybe that one from the garage fire for $750 (down the street from me) is still available. You could buy it and then find out. Then use it for a jig to make a frame out of some other lightweight material.

And then....

Get the engine for a few grand from the guy in Beverly Hills.

Or get the burnt GT4 in La Habra, and then get the GTO body kit...

Heck, you could probably build up a $50k GTO kit car for... for... for... Well.. maybe something less than $50K... Maybe...

 

Someone said the engine and gearbox combo was around 500 pounds, and that sounds realistic from what mine felt like shoving it around the garage, its a pretty heavy unit. The calipers, hubs, rotors, and axles are also pretty heavy, and the interior is packed full of fiberglass and insulation panels. The headlight assemblies are pretty heavy, and dont forget about 70 extra pounds for the US bumpers, plus the door beams. It seems to be built more like a truck than a light sports car. So lets say you start with 2900 pounds:

engine/gearbox 500 pounds

brakes and suspension 300 pounds

bumpers 70 pounds

seats and interior 300 pounds

glass 200 pounds

battery 30 pounds

radiator 35 pounds

coolant 50 pounds

fuel 100 pounds

headlight assemblies 50 pounds

Taking all that away the basic shell still weighs almost 1500 pounds, quite a heavy lil bugger.

 

Doesn't the US version have extra frame bracing in the doors and I think the bottom of the trunk compaired to the Euro? I have often wondered if this can be cut out?

 

Not only is the trunk more heavily reinforced on US cars, but so is the front framing. From what I seen of a euro car front frame section, I would say the US car has over twice the steel framework, forward of the suspension pickups.

I would question though if all the steel framing were replaced with aluminum, if it would carry the same strength. I would start in other areas to lose weight before I would ever consider that thought. Like replace all the sheetmetal with light weight fiberglass or carbon fiber. Strip out all the extra insulation. Lighter brake rotors and calipers. Lighter seats. Have any of you picked up a door panel? They are leather covered fiberglass, and pretty heavy. But all in all I will leave mine alone as is, I really like it the way it is, even if it is kinda a hog.

 

The rear frame section can be removed and converted to Euro specs. I removed all of mine during the restoration but found it wasnt very heavy once out in a pile on the floor. The rectangular tubing is quite thin and light. All together front and rear I cant see the US frame weighing anymore than 15lbs heavier than the euro version. The front sections are basically the same just with larger dimensional tubing and some studs to mount shocks. The rear is much different. A carbed 79 308 weighs 3080lbs minus the smog but with eveything else on board and working including the air. Ill weigh mine once its back together just to see how much I shed.

P.

 

I've got a Euro that was never federalized. It weighs in around 2750 lb wet according to the OM(haven't actually weighed). So the federalization bracing, bumpers, etc. add about 500-600lbs.

I agree, the first place to start losing weight are the body panels & doors. They're fairly heavy gauge mild steel. I suspect that you could save 400-600 lbs just by replacing them with lighter material. I'd go for Al or carbon fiber panels. The doors are also very heavy, with fairly thick steel frames. Again, Al or carbon fiber replacements.

I suspect that once you had the external panels off, other weight reduction opportunities would present themselves.

Hmm, there's a place in the UK that makes replacement body panels & panel sections. They must have forming jigs, wonder if they'd consider making up a set of Al panels with similar strength to the OEM steel ones....

 

it's not just cutting wieght but where you cut it from that makes the biggest difference. i remember BMW going thru and shedding pounds from the M3 to make the CSL and having to do it in the right areas to keep the 50/50 as close as posible or the weight loss was useless.

so if one really wanted to make a wicked tract car $$$$ no object. i'd redo the frame and panels while trying to keep the 50/50. an aluminum frame would be BIG $$$$$ though. the rest would be doable. i think it would cost around 100k to do right.

mental excercise and all, not really worth it. get a 'kit' car and stuff the ferrari drive train in. low weight and cheaper. ofcourse the purist would freak out. tempting though, there are a few kits that have some nice looking cars. a longitudal 308 with TT's would make a screamer.

 

I'll weigh the remains of the one were currently breaking (as soon as its in bits)

 

sounds like an autopsy

 

So we have a roughly 400 lb difference between US and Euro. The bumpers which I have done are about 90lbs with brackets, where is the rest?

 

Door bracing and cats, plus i think US versions have added insulation in the trunk. There is probably more.

 

I may have to pull a door panel and take a look. I wonder if it is bolted in there?

 

The US spec crash bar is part of the door shell. The Euro glass cars have no crash bars at all and the door weighs nothing, the steel US ones are very heavy but I would rather have the weight than have some SUV front bumper on my lap in a parking lot accident. Some other additional items are the thermo couples under the forward passenger floor boards on US cars, additional panels covering even more insulation forward and behind the engine and the fiberglass subfloor in the trunk to make room for the rear bumper shocks as well as loads more of insulation. The US cars also have the full size spare tire. Lets not forget air injection pumps, thermal reactor muffler, twin distributors, vacuum pump on carb cars for HC evacuation after shut down, converters and plumbing galore. No wonder they are slow, yanking all that extra stuff makes a big difference.

 

Steel is pretty amazing and there are very high grades available (check out bicycles). Triangulation is good but expensive to produce (check out steel framed Bimota motorcycles).

Motorcyclists use titanium and carbon fiber exhaust systems, a change which shouldn't be unlivable, although expensive.

It's always surprising how heavy just the sound insulation is, though. I wonder how many pounds are on a 308. Removing it should improve safety, even, as long as it's not there for fire protection.

There is some light stuff made for airplanes. Might be expensive. One might strip out all the insulation, reassemble the car and see if it's personally tolerable. Add some light aircraft stuff and re-try. You may never like the results, though.

Too bad there isn't a Bose active noise cancellation system for auto interiors, like the headphones!

 

Ive seen noise cancellation systems in nissans under the passenger front seat back in the eighties. Its a box with a speaker in it to cancel the "boom" 4 cylinder engines produce at specific rpms. Its a great idea but it doesnt solve the heat issue which is the number 1 problem in the mid engine/front rad cars along with the smog stuff.