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MGB My MGB weighs what?

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Nunyas

Nunyas

Yoda
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So, as you folks may or may not know, I recently pass my CA emissions testing. Part of the testing they put the car on scales. I noticed the weight on the rear axle was 1300 and change with a driver in the car. I'll have to get the results sheet and look at it if anyone wants the exact figure. I'm looking at Moss and they're quoting the '75 and '76 MGBs as have a curb weight just under 2600lbs (2590lbs to be precise). Compared to *most* vehicles this is in feather weight catagory, but I didn't think the car weighed that much. Looking further on Moss's site I found that they're quoting '62 to '70 MGBs to have a curb weight of only 2030lbs.

That got me thinking and trying to figure out where the extra weight comes from. Ok, there's the bumpers. Yes, the rubber bumpers do weigh more, but not 560lbs more. I've had the front bumper off of my '76 and I'd have to estimate it to be around 30lbs. Assuming the rear weighs about the same, that comes up to 60lbs for the bumpers. That still leaves a quarter ton of added weight. Later cars have the tube axles, which are also heavier, if I'm not mistaken. Tony weighed them relatively recently (without guts), I think the tube axle housing came out to about 70lbs heavier than the banjo type? That brings us to 130lbs accounted for; 460lbs to go. Hmmm... the leaf springs on RB cars are longer than the leaf springs on CB cars. So, RB leaf springs probably weigh more, but I can't say how much more. If I were to guess, I'd guess each leaf is maybe 15lbs more each tops. Smog pump, that's probably 20lbs...

Maybe this is an exercise in futility, trying to figure out every thing that was added to the car to make it weigh 560lbs more than the 'early' cars. Maybe I should just go back to pondering what stuff I should put on my next order. Still, it's one of those things that would be nice to know. You know, to add to the Encyclopedia of Useless Knowledge...
 
Rob,

You have graduated from the status of YODA to the status of EAR (Extreme Anal Retentive)... /ubbthreads/images/graemlins/smirk.gif

/ubbthreads/images/graemlins/cheers.gif
 
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the leaf springs on RB cars are longer than the leaf springs on CB cars.

[/ QUOTE ]

Really? Don't think so.
 
aw shucks... my mind wanders from time to time, but I'm lucky enough that it still comes back to me.

Still, is there a Weight Watchers club of sorts that I can have my B sign up for? After seeing the difference in weights over the years, I'm feeling like my car is a bit... pudgy. I can only dream of how much more athletic the car would be weighing 600lbs less.
 
[ QUOTE ]
[ QUOTE ]
the leaf springs on RB cars are longer than the leaf springs on CB cars.

[/ QUOTE ]

Really? Don't think so.

[/ QUOTE ]

They're not then? So, then the only diff is the RB springs are 7 leaf instead of 6, and a higher spring rate. hmmm... darn it all back to the drawing board.

Ooo... if they're the same size, does that make them interchangeable? Say, instead of using stock RB springs + spacers to lower the rear, one might swap for CB springs?

I think I assumed they were longer on RB cars, because I'd read something that mention RB cars having a different location for mount point for the front eye of the leafs.
 
I've put chrome springs on rubber bumper cars...GT springs on roadsters & vice versa....you might want to try a set of real early roadster springs & chrome car rebound straps - of course you'll have to change the arms on the shock to chrome bummper arms.

Or, you could remove one of the leafs to see if it lowers your car.
 
So where is the 570 lbs? If 50 or 60 lbs comes from the bumpers, then where does the 510 or so lbs come from? The cars aren't that different! /ubbthreads/images/graemlins/crazyeyes.gif PJ
 
Well, there's probably 100 pounds in both bumpers...the places on the body where the bumpers attach are heavier...the doors have side impact beams in them that earlier cars didn't...there's some weight in all the emissions stuff (pipes, carbon cannisters, vapor separator & pipes/hoses)...it all adds up a little at a time.

Heck, I took almost 60 pounds of undercoating/sound proofing from underneath/inside my GRM GT!
 
Yeah....I was just going to say....dirt and undercoating...got a pile of tools kicking around in the car?
 
well at 1300 and change with a driver in the car isn't too far off from the quoted curb weight for my car. That's with a tool bag in the trunk. So, the weight isn't too concerning. It's just trying to figure out what all was added to the cars over the years to make them weigh nearly 600lbs more than the start... /ubbthreads/images/graemlins/smirk.gif

I reckon it's like Tony says, all those emissions bits add up, with major contributors being bumpers and necessary frame strengthing at the mount points..
 
Late cars have a lot of heavier components than early (62-67) ones. The transmission is much heavier, the rear axle is significantly heavier, smog gear, cat converter, etc. are not found on earlier cars. When you include the bumper mounts with the bumpers, rubber bumpers are somewhere around 180 pounds all told. Chrome bumpers with mounts are maybe 50 or so if memory serves. Doors are slightly heavier, steel hood adds quite a bit of weight over aluminium and the larger fuel tank will add a bit of weight. Even little things add up like the heavier dash assembly and seats.
 
All this just brought up a question in my head... which are heavier? Rostyles or wire wheels? Which has more rotation mass?
 
Rob,
My '71 B weighs 546/489 in the back left/right corners stripped down Sebring style with a half tank of fuel and my fat butt sitting in it. That makes me think - is Moss's early B weight listing with an empty boot and empty fuel tank? That could easily be 200 lbs. The extra leaf springs should only account for 25 lbs or so. Add the weight of the bumper (45 lbs?) 10 lbs for the fuel separator & hoses, marker lights, etc...
 
My guess would be thus: The whole reason for the goofy looking rubber bumpers was increased saftey standards so there was probably all sorts of increases in stiffening/strengthening which would certainly add up...quickly! I imagine it took quite a bit of extra steel to meet the increased standards. Not to mention that the air pump and related are no light weights.

Just goes to show I guess, the older the car, the more fun! Gotta get a car that predates the governments attempts to counteract the "Darwin effect" /ubbthreads/images/graemlins/smirk.gif /ubbthreads/images/graemlins/rolleyes.gif
/ubbthreads/images/graemlins/cheers.gif

JACK
 
Bugeye 1433 lbs according to the liturature.
 
If I had to guess, I would say that wire wheels are the same weight or perhaps slightly heavier than rostyles. But that's just a guess, and assuming these are stock wire wheels.
 
I know the wires are considerably lighter than the knock-off mini-light replicas. I don't remember the exact numbers, but around 6 lbs lighter each? The Minataur brand that I have are 19 lbs each! I can't imagine a stock steel wheel being that heavy!
 
The Bentley Complete Official books auctually claim that the 75-76 cars are the lightest of all Bs. I don't have the books in front of me but anyone out there that does can look up the curb wieghts in the front specs section. I don't really beleive them though.
 
That's definitely not correct. There is nothing the factory ever did that could lighten the car enough to make up for more added weight than the rubber bumpers, tube rear axle and 4-sync transmission.
 
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