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The Elephant In The Room: unloading the load from a B-body.

I have the original 8 3/4 rear in my Belvedere. I haven't seen any place to cut weight there besides getting an aluminum center section. There is my aluminum wheel cylinder project, but that hasn't produced anything viable yet. Up front, I have looked closely at my upper and lower control arms. I don't really see any places to reduce weight there (holes) safely, so they are stock. There are aftermarket, tubular pieces available, however the ones I have seen so far weigh more than the factory pieces. I am looking into some titanium fasteners to replace some of the steel hardware, but the main parts remain stock.
 
Based on my limited experience, I'd say it's hard to get into real weight loss without spending a lot of time and money on it. Generally, the answer is to buy aftermarket parts. Stuff like my 10" drum spindle Wilwood brakes shaved over 60 lbs off my front end. I'm not making my own lightweight disc brakes at home though so it's either pay the piper or do it yourself. Even if you do have the tools, equipment and skill to produce sanitary and safe pieces you're certainly ahead of the game but that kind of ability does not come overnight and it does have a high investment cost if you chose quality tools.

If you don't care about appearance, stuff can merely be yanked out and if necessary replaced with something that conforms to whatever rules you decide to run your car under. That's usually dedicated race car stuff though. Street machines will always straddle the line between race and passenger car identities. An unpainted, brake-bent sheet aluminum dash with three Auto Meter gauges and diamond plate panels riveted to flimsy fiberglass doors is light for sure but that approach won't get you much action on the street.

And then there is FMJ who looks at every single part of his car and tries to ascertain how it can be made lighter while retaining most or all of the particular parts' original strength and appearance. Ashtrays, door handles and strikers, steering wheels all get the treatment. Generally nobody that I know of other than FMJ (myself included) decides they're gonna shave off a a pound or two by RE MAKING their steering wheel out of aluminum while keeping it looking like an original part. That right there is a key element to this methodology. Some people may not see the value of going to that level of detail. Plus, not everyone can sustain that kind of focus and determination either, especially when cars come and go in life. Maintaining that bucks down, DIY strive and drive with one car for thirty years is pretty unique.

I'd say I have my feet planted in both worlds but tend to favor buying stuff over getting too deep into sleight-of-hand trickery. There's a bunch of brackets and such you can't see under my dash that have been massaged. I stripped off all my undercoating and repainted the bottom of the car with factory-style grey dip epoxy primer. I get rid of all unnecessary wiring, creature comforts and whatever dead weight can be jettisoned in the name of better performance but I don't leave that stuff as-is either. I take the time to search out and obtain things like factory correct heater and radio delete plates. Some of those things took me years to track down.

At one point I even obtained an early A body right-side heater delete vent box from someone in Australia because that's what the Super Stock Hemi Darts and 'Cudas had. They were standard production parts down there for several years because Australian cars have the heater box on the left (right-hand drive). I have to think I'm the only person that's ever done that. The guy who sent it to me thought I was nuts since shipping the thing was like triple what the part was. But try to find one in North America!

Conversely, I do have plenty of mail-order pieces like a Kirkey aluminum seat, a pin-on fiberglass hood, a QA1 front end, an aftermarket dash with digital gauges and Wilwood brakes. None of those parts are over the top blingy gee gaws though so even at first glance they can blend in to the background unless you take a second look.

Details, details.
Never did spend much on my cars....and got my 66 Belvedere down to 2950 without much effort. It started out at 3370 and the 2950 figure still had the stock front end and K-frame along with the factory working AC still on it. It also still had the 15x7 cop car wheels. Just wish I had kept the AC setup as the car won't be used as a dedicated race car anymore like I had in mind several years ago but can always install an aftermarket kit. And if you're wondering about the 3370 figure.....it was a /6 auto car but was at the track with it anyways. Went 7 rounds with it one night and there's nothing better than being the underdog lol but, going that slow isn't all that fun.
 
I have the original 8 3/4 rear in my Belvedere. I haven't seen any place to cut weight there besides getting an aluminum center section. There is my aluminum wheel cylinder project, but that hasn't produced anything viable yet. Up front, I have looked closely at my upper and lower control arms. I don't really see any places to reduce weight there (holes) safely, so they are stock. There are aftermarket, tubular pieces available, however the ones I have seen so far weigh more than the factory pieces. I am looking into some titanium fasteners to replace some of the steel hardware, but the main parts remain stock.
You can do some trimming on the upper and lowers....if it isn't going to be on the street. No pot holes etc at the track I hope plus if you're taking weight off the car, it's less stress on the suspension parts. Keep in mind that some of our B bodies weigh in close to 4000 lbs.
 
That’s impressive for a B Body.
When I say without much effort.....scraping undercoating off doesn't really apply lol. This thing had a LOT of that under there. I did a few cars over the years and this one was the worst of them all. Seems kinda odd that someone in the middle of Texas would want to pay extra for that. I have the invoice on the car and even talked to the relatives of the dealership. They still own the property and the garage but they don't sell cars anymore.
 
I might have been one of the first in the country to get one and subsequently one the of handful of people that pulled the trigger on one. I haven't seen any others out in the wild.

The problem was they were too expensive. I paid $600 for it but the last time I saw one for sale new it was over $900. Too small of a market for them as well since if you had any real power you'd switch to a Dana or 9". I've thought that people failed to grasp what was done to strengthen them though and would pass them off as another 8 3/4 time bomb waiting to explode. Right or wrong, racers would never spend the coin on something they perceived would fail in short order. Sucks for them!

I've run it down the track several times and street driven it plenty, no problems. The caps are through-bolted through the front of the pumpkin, it's stout. The bottoms of the caps are also counter bored into the main housing to prevent cap walk. That fit was TIGHT, like I had to massage the bore a bit to get the caps on, even after putting them in the freezer.
Check this ad out - Mopar 8 3/4 rear differential Magnesium Rare Mickey Thompson | Transmission & Drivetrain | Winnipeg | Kijiji - Canadian $$ also.
 
Based on my limited experience, I'd say it's hard to get into real weight loss without spending a lot of time and money on it. Generally, the answer is to buy aftermarket parts. Stuff like my 10" drum spindle Wilwood brakes shaved over 60 lbs off my front end. I'm not making my own lightweight disc brakes at home though so it's either pay the piper or do it yourself. Even if you do have the tools, equipment and skill to produce sanitary and safe pieces you're certainly ahead of the game but that kind of ability does not come overnight and it does have a high investment cost if you chose quality tools.

If you don't care about appearance, stuff can merely be yanked out and if necessary replaced with something that conforms to whatever rules you decide to run your car under. That's usually dedicated race car stuff though. Street machines will always straddle the line between race and passenger car identities. An unpainted, brake-bent sheet aluminum dash with three Auto Meter gauges and diamond plate panels riveted to flimsy fiberglass doors is light for sure but that approach won't get you much action on the street.

And then there is FMJ who looks at every single part of his car and tries to ascertain how it can be made lighter while retaining most or all of the particular parts' original strength and appearance. Ashtrays, door handles and strikers, steering wheels all get the treatment. Generally nobody that I know of other than FMJ (myself included) decides they're gonna shave off a a pound or two by RE MAKING their steering wheel out of aluminum while keeping it looking like an original part. That right there is a key element to this methodology. Some people may not see the value of going to that level of detail. Plus, not everyone can sustain that kind of focus and determination either, especially when cars come and go in life. Maintaining that bucks down, DIY strive and drive with one car for thirty years is pretty unique.

I'd say I have my feet planted in both worlds but tend to favor buying stuff over getting too deep into sleight-of-hand trickery. There's a bunch of brackets and such you can't see under my dash that have been massaged. I stripped off all my undercoating and repainted the bottom of the car with factory-style grey dip epoxy primer. I get rid of all unnecessary wiring, creature comforts and whatever dead weight can be jettisoned in the name of better performance but I don't leave that stuff as-is either. I take the time to search out and obtain things like factory correct heater and radio delete plates. Some of those things took me years to track down.

At one point I even obtained an early A body right-side heater delete vent box from someone in Australia because that's what the Super Stock Hemi Darts and 'Cudas had. They were standard production parts down there for several years because Australian cars have the heater box on the left (right-hand drive). I have to think I'm the only person that's ever done that. The guy who sent it to me thought I was nuts since shipping the thing was like triple what the part was. But try to find one in North America!

Conversely, I do have plenty of mail-order pieces like a Kirkey aluminum seat, a pin-on fiberglass hood, a QA1 front end, an aftermarket dash with digital gauges and Wilwood brakes. None of those parts are over the top blingy gee gaws though so even at first glance they can blend in to the background unless you take a second look.

Details, details.
Well said Rmchrgr.

AAAhhh, the lightweight years of the 60's and early 70's. Who could, would forget the skunked Silver Bullet or Motown Missile programs.
I think my approach is simply based on generational reflection. 600 miles away in New York, I was simply too far and too young during the dawn of factory STOCK and SUPER STOCK. Later on, it was my awareness of those experimental years in STOCK and SUPER STOCK that has led to this light headiness now.

Yes, as we all say, we're all happy to have grown up in our respective eras whether it be the 50's 60's 70's 80's and beyond, but I'm happy that I grew up partly in the 60's and barreled through from there on. It was truly a hands on life experience.
When it came to cars, I might have missed some pivotal moments and places in history, not that New York didn't have its own, but that doesn't mean it can't be brought right back to the surface for a new generation with a little more flare and dare.
What I did see first hand was the recreational part of street car culture and then I witnessed and participated in the middle to tail end events of high stakes SUPER,SUPER STOCK street action. When I say SUPER,SUPER STOCK, I really mean the post '67 era when the cars that had been secretly developed over a short period were in the ring.
It was truly a special time to watch guys improvising (sometimes delinquently) under shade trees in order to let it all hang out on the Blvd's thereafter.

Of course the real hinge here for all of us is the ever so coveted SUPER STOCK years when the factories finally dipped their skillet into the fire to save their own reputations through a variety of "behind The Curtain" programs. Infamous code names such as WO's and RO's, BO's and LO's, Swiss cheese and ThunderBoltz, Z11's and ZL1's will forever be inextricably linked to signage such as Woodward and Ramcharger garage, Dearborn Steel, Kar-Kraft, Nunzi's, Apollo Trick Titanium and Nichels Engineering just to name a few. It is here where the fascination is clear and nuclear.

Aside from wishing to have been flies on the walls of any of these facilities at the very least, I can only imagine what any of us working as go-for coffee boyz or mechanics assistants would have done with all those recourses on our laps.

Perhaps that's what brings us here to read.
If I were thinking then how I think now, cars would have been floating off the the showroom floor.
 
When I say without much effort.....scraping undercoating off doesn't really apply lol. This thing had a LOT of that under there. I did a few cars over the years and this one was the worst of them all. Seems kinda odd that someone in the middle of Texas would want to pay extra for that. I have the invoice on the car and even talked to the relatives of the dealership. They still own the property and the garage but they don't sell cars anymore.
My car most likely had double undercoating because a lot of weight came off when I took it all off, and I mean all of it. Never mind the daughter, I could have passed for a Coal Miners Son.
 
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My car most likely had double undercoating because a lot of weight came off when I took it all off, and I mean all of it. Never mind the daughter, I could have passed for a Coal Miners Son.
And I haven't done the wheel wells yet and just might not!
 
I have the original 8 3/4 rear in my Belvedere. I haven't seen any place to cut weight there besides getting an aluminum center section. There is my aluminum wheel cylinder project, but that hasn't produced anything viable yet. Up front, I have looked closely at my upper and lower control arms. I don't really see any places to reduce weight there (holes) safely, so they are stock. There are aftermarket, tubular pieces available, however the ones I have seen so far weigh more than the factory pieces. I am looking into some titanium fasteners to replace some of the steel hardware, but the main parts remain stock.
True to this, that there isn't much weight that can be removed from an 8-3/4 except the pumpkin. But there are bolt on parts that can either be lightened or replaced with lighter similar parts. I'll explain when I get a chance shortly.
 
WOW!!! That is awesome! Never seen one before, totally mind blowing. Seen plenty of M/T magnesium B/O/P versions but never for a Chrysler rear. Yes it's pricey but how many of those ever existed? Could very well be the only one left? It's about $3,300 US dollars.

That's just a crazy part.
IIRC, The Ramchargers were experimenting with magnesium pumpkins on their drag rails. Only a few carriers were made of the stuff and then they went elsewhere. They also experimented with their own Ramcharger branded carriers for the Dana's. Pro-stock territory. No business on a street door car.
 
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My car most likely had double undercoating because a lot of weight came off when I took it all off, and I mean all of it. Never mind the daughter, I could have passed for a Coal Miners Son.
IMG_3064 sm.jpeg

This pile is the remnants of the undercoating that was removed from my Duster. The whole job was done with a torch and scraper. Whatever residue left was removed with Goo Gone. I have a lift so thankfully I didn't have to lay on my back to do this but it was still a tough, tedious and dirty job. So many hard to reach spots and uneven surfaces, it almost got the best of me. I made sure to try and capture every single bit that I could to be able to weigh it at the end. Including both wheel wells, the grand total was 12lbs.

You read that right - 12 FRIGGIN' POUNDS!!! Took a while to swallow that. I'd read many times where guys were seeing savings of well over 20lbs. I have to question the veracity of some of those claims because this car had the full Monty job and they weren't stingy with it.

I detest working on rough, dirty surfaces so the main goal was to clean the underside with the added benefit of removing a nice chunk of weight. Got one out of two...
 
View attachment 1564736
This pile is the remnants of the undercoating that was removed from my Duster. The whole job was done with a torch and scraper. Whatever residue left was removed with Goo Gone. I have a lift so thankfully I didn't have to lay on my back to do this but it was still a tough, tedious and dirty job. So many hard to reach spots and uneven surfaces, it almost got the best of me. I made sure to try and capture every single bit that I could to be able to weigh it at the end. Including both wheel wells, the grand total was 12lbs.

You read that right - 12 FRIGGIN' POUNDS!!! Took a while to swallow that. I'd read many times where guys were seeing savings of well over 20lbs. I have to question the veracity of some of those claims because this car had the full Monty job and they weren't stingy with it.

I detest working on rough, dirty surfaces so the main goal was to clean the underside with the added benefit of removing a nice chunk of weight. Got one out of two...
I beg under oath that my cars dirty under sides were heavier than even 20 Lbs. I've got it written down somewhere, but unfortunately not in my master log.
I know that b-bodies are not that much longer or fatter than an A body, but it could be applied thick or thin depending on dealer order, sprayer behavior and the actual formula of the stuff. Not sure if coatings differ from dealer to dealer or brand to brand.
I've noticed over the years when helping some guys with the removal that some undercoatings were dry and flakey, almost on the verge of being dust whereas other were thick and almost feeling wet, like new asphalt tar. I mean chunks that looked like parts of a meteor. LOL
 
My 65 Belvedere I only has a relatively thin coating of the stuff on it, maybe because it is a stripper, low end model. I did weigh what I scraped from the driver door, it was 2 pounds of the stuff and it practically fell off. My 65 Sport Fury has an incredibly thick coating of the stuff. On the gas tank it is so thick that you cannot tell there are ribs on the tank and forget about seeing any support straps. I swear that it is easily over an inch thick in places. I am still scraping that stuff off of the Fury, but I've only had it 43 years.
 
Here's a before shot. This was a combination of still flexible, tar like stuff and dirty, crusty dust. All of it sucked.
IMG_2950.jpg


This is after removal and sealed with a couple coats of PPG DP90. The underside of this car was spotless before the epoxy sealer. Probably added 2lbs back with the epoxy. :screwy:
IMG_3426.jpg


I used thinned out Raptor Liner to seal the wheel wells to retain a quasi factory look. Yes, the wheel well is pounded out on the left side above the lip for tire clearance. This is two thin coatings. The thinned out Raptor Liner has some texture but is not rough like the factory undercoating.
IMG_4665 copy.jpg


Next time I decide to remove undercoating from a car it's going to the media blaster.
 
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