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

[fullmetaljacket]

Badvert, you asked if there's anymore that can be done to an 8-3/4 rear to lighten it short of shortening the housing itself, no, but if you're looking at bolt on parts, then yes.
This is a trick that I have mentioned here before and yet to do it myself once the parts and time allow. They fall under the unsprung weight category which is outside of the rear itself. The parts consists of the rear drums, shoes, lug nuts, wheels, tubes, backing plates and wheel cylinders.

 

[fullmetaljacket]

Badvert, you asked if there's anymore that can be done to an 8-3/4 rear to lighten it short of shortening the housing itself, no, but if you're looking at bolt on parts, then yes.
This is a trick that I have mentioned here before and yet to do it myself once the parts and time allow. They fall under the unsprung weight category which is outside of the rear itself. The parts consists of the rear drums, shoes, lug nuts, wheels, tubes, backing plates and wheel cylinders.

Rmchrgr. This is the first time I've seen this image. Your cars undercoating from the factory/dealer looks skimpy, almost like a dusting. It might be that south west or south east cars that get ordered to have the stuff sprayed on get a skim coat as apposed to north east and mid north cars getting a volcanic gunkin'.
The Epoxy PPG coating looks fantastic and slippery, which adds some aerodynamic benefits. Underbelly wind management is a top secret with the stock car Boyz.

 

[fullmetaljacket]

This may be sacrilegious for some Mopar purists.
Menu: Take one 8-3/4 or 9-1/4 Dana rear housing and cut to size if needed. Either way, have GM axle flange ends welded on to accept a GM brake system. Add GM backing plates (may be lighter than Chrysler), GM brake shoes, GM springs, GM wheel cylinders and most importantly aluminum GM brake drums found on 80's Firebirds, Malibu's and Camaro's.

I can't see if someone is already going through a new rear end build, that the axles can not have their flanges drilled to have a GM bolt pattern to accept the GM aluminum drums. The only thing is that this dictates the usage of a GM pattern wheel which can make it all expensive, but if you are starting from scratch and want to remove rotating weight to the tune of several pounds. this might be the move.
Once I talk this through with Dr Diff, I'll circle back with the news.

 

[HEMI-ITIS]

That drive shaft loop has ALOT of hardware. When I went to a 4 inch aluminum driveshaft it did not fit in the hoop,so we had to disassemble the hoop and bend it so the new shaft would fit and then welded it back together. I did not weigh the leftovers. This was part of my weight reduction,lost 200 lbs!

 

[fullmetaljacket]

That drive shaft loop has ALOT of hardware. When I went to a 4 inch aluminum driveshaft it did not fit in the hoop,so we had to disassemble the hoop and bend it so the new shaft would fit and then welded it back together. I did not weigh the leftovers. This was part of my weight reduction,lost 200 lbs!

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Itis. That car of yours is sure heavy, but it is fast. I can just imagine if it were 3300 Lbs.

 

[Cranky]

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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

The undercoating on my car was thick as could be but with this car I got smart and used a heat gun that I picked up from an estate sale when I was working with those. Way better than using some kind of fire. What surprised me is that this car was sent to the middle of Texas where it's nice and dry.....don't remember exactly what it weighed but it was over 30 lbs worth!

 

[Big bill]

This may be sacrilegious for some Mopar purists.
Menu: Take one 8-3/4 or 9-1/4 Dana rear housing and cut to size if needed. Either way, have GM axle flange ends welded on to accept a GM brake system. Add GM backing plates (may be lighter than Chrysler), GM brake shoes, GM springs, GM wheel cylinders and most importantly aluminum GM brake drums found on 80's Firebirds, Malibu's and Camaro's.

I can't see if someone is already going through a new rear end build, that the axles can not have their flanges drilled to have a GM bolt pattern to accept the GM aluminum drums. The only thing is that this dictates the usage of a GM pattern wheel which can make it all expensive, but if you are starting from scratch and want to remove rotating weight to the tune of several pounds. this might be the move.
Once I talk this through with Dr Diff, I'll circle back with the news.

Yuck that’s going to far.

 

[fullmetaljacket]

Yuck that’s going to far.

That's just it, we're trying to get farther ahead of the competition by carrying less load. LOL.

 

[rmchrgr]

Yuck that’s going to far.

I have Chevy rods in my motor.

 

[Badvert65]

I bought an iron version of the GM drum to see if just the drum could be adapted to Mopar brakes. The GM is 9.5 inch x 2 3/4 inch. You would definitely need ALL of the GM brake hardware as it is just not really possible fit the 9 1/2 drum to the Mopar 10 inch brakes. But I don't see why the GM drum couldn't have the wheel stud holes slightly 'ovaled' and the center register slightly enlarged to accommodate the Mopar axles.
FYI, there are some old Mercedes (late 60's) models that used 10 x 2 1/2 inch aluminum drums with a 4 1/2 inch bolt pattern. The bad news is that these are nearly impossible to find, even used (and VERY expensive).

 

[Cranky]

I have Chevy rods in my motor.

Do they have the 'bow-tie' on them?

 

[fullmetaljacket]

Every now and then, our cars will cross pollinate parts just to make things work more efficiently or in this case, save weight. I do agree that it is a lot of coin and effort for the sake of shedding a few pounds........ if that.

I have a 1-wire GM 140 amp alternator that spikes the MSD enough for its needs and it actually weighed 2 Lbs of so less than the 60 amp Chrysler unit.

 

[Cranky]

Every now and then, our cars will cross pollinate parts just to make things work more efficiently or in this case, save weight. I do agree that it is a lot of coin and effort for the sake of shedding a few pounds........ if that.

I have a 1-wire GM 140 amp alternator that spikes the MSD enough for its needs and it actually weighed 2 Lbs of so less than the 60 amp Chrysler unit.

I have a GM 1 wire alternator on the shelf for mine too if it ever gets put back together....

 

[Badvert65]

I don't mind cross-pollination either in the interest of going faster. I have a Nippondenso alternator on my car. It crosses the scales at 5.7 pounds.

 

[fullmetaljacket]

Now in region #3 (back end of the car) A closer look will reveal a modest amount of points where pounds can be trimmed or repositioned further back.
Starting at the very border between region #2 and # 3 are the leaf spring hangers.
The offset and adjustable rear leaf spring hangers from either Direct Connection of Dr. Diff are heavy and rightfully so, they are supporting the front of the springs and differential. A lot is reliant on those two hangers.

These are from Dr. Diff and after all adjustments and locations for the front spring eye were met, a titanium spring eye bolt and nut were given the nod as well as nuts and washers for the four mounting studs on each hanger.
The old Direct Connection adjustable hangers in stock form were 4-1/2 Lbs.
These were 3 Lbs, shaving off 1-1/2 Lbs and not counting the bolts and nuts.

 

[fullmetaljacket]

I don't mind cross-pollination either in the interest of going faster. I have a Nippondenso alternator on my car. It crosses the scales at 5.7 pounds.

How much amps does it put out. I was on the fence about those when they first came out because of concerns it would not be enough for my in tank Aeromotive 1000 fuel pump, electric radiator fan, MSD 6AL and factory lights.

 

[fullmetaljacket]

Big Bill, I know you know we ain't snapping on you, but to your point, here's a purist that runs everything stock right down to the dual points. With the exception of the street BF Goodrich tires and a four speed instead of its original 3 speed, this REAL street driven REAL Max Wedge lightweight is pure.

 

[Badvert65]

I got the 90-amp alternator. I am not running as much eclectically demanding stuff as you.
Any chance you have a pic of those spring hangers installed?

 

[rmchrgr]

I had a Denso 60 amp in my '68 Coronet and have run them on my cars for years. The '68 had all the typical lights and stuff including front bumper running lights, side markers and license plate light. That car also had EFI with an in-tank electric fuel pump and it always charged adequately. One thing I did not have was an electric fan so I'm not sure if there would have been a dip in output with one of those. The headlights were on relays which always helps take the load off. No clue what the weight difference vs. a GM one wire unit could be though.

Modern CD ignition boxes don't generally require a lot of current because it's all transistorized or digital circuitry inside. Stuff like electric fans, water pumps, fuel pumps, stereos, extra lighting, A/C, etc. are typical high-amp draws.

The Toyota/Denso 60a alt. is internally regulated so you have to run a sense wire to the B+ output stud, wherever that may be on your car. The nice thing about that is it allows you to get rid of the problematic voltage regulator. Also need to run a wire to an ignition-switched 12V source to turn it on. Sometimes the GM one wire alternators are easier to deal with in that regard.

There are very small and light 'race' versions of the Denso alternators out there, some of which come in around 5lbs. I'm not sure if Powermaster or East Coast Electric are still around but both companies had similar offerings. Most of the time those types of alternators don't put out enough juice to run on the street though, especially at idle. With a fan, water pump and electric fuel pump one of those little things would be marginal at best.

The Denso 60a is a proven upgrade. AndyF makes brackets for them too so you don't need to cobble stuff together to make it work. I probably wouldn't run anything else.

This was on my Duster from about 10 years ago. The AR Engr. brackets and spacers allow it to bolt up like a stock part. Not super expensive either and the alternator itself is usually available through parts stores or Rock Auto.

 

[rmchrgr]

That drive shaft loop has ALOT of hardware.

Yeah, it is HEAVY AF. No BS I think it weighs 15 lbs. I have considered welding the halves together to get rid of the bolts. It's just a heavy part though, not sure if removing the bolts would amount to much.

Metco makes a nice one. They have them for '66-up B bodies but don't list one specifically for Early B's. Only problem I'd have getting one from there is whether it would line up with the preexisting holes in my floor.