How much weight gain from adding a Dana and roll cage.

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max512wedge

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My 1972 duster weights 3240 with a small block and 8.75 rear end and a full tank of fuel (16 gallons) all steel and glass.soon to be a 512 with victor heads. Question what would be the difference in weight from a 8.75 rear to a Dana. What would I need cage wise to run low 10’s height 9’s and what would the weight be for the cage and frame connectors. One more question could I just run 5 gallons in my stock fuel tank so I could save 11galx6pds= 66 pounds from having less fuel weight in my car. I know I’ll probably need to put a fuel cell in at some point but can I do this or would the fuel slosh around to much and cause fuel starvation problems. Thanks Guys

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6 pt cage is what you need according to nhra rules, I'm going to run low 10s but chose a art Morrison 10 pt which is a 12 pt cage for chassis stiffness but also my car will be just drag racing.
I imagine the dana is probably between 60-70 pounds difference. If it was Saturday I'd go out and weight my dana. Mine is 46 inch flange to flange so it is lighter by a couple pounds just due to less steel.
 
Dana’s are damn heavy, so are 9 1/4’s. If your car is race only, the more cage the safer and stiffer the car will be. 9’s-10’s ain’t no joke, things get crossed up right quick at those speeds and velocity.
 
Went from an 8.75 to a Dana years ago on consecutive weekends when I was racing all the time.
Close to 70 extra pounds.
That said, I saw zero difference on the time slips. I suspect the Dana must be more efficient for it’s extra weight to not hurt the time slip at all.
Regards the frame connectors and cage. Cage might make a tiny bit of difference, the frame connectors you might actually gain some ET from.
Lots to be said for making a unibody car a much stiffer “ one piece” deal.
All these changes I bet you would be unlikely to lose half a tenth, just good upgrades all around.
 
MOPARMAGA said:
6 pt cage is what you need according to nhra rules, I'm going to run low 10s but chose a art Morrison 10 pt which is a 12 pt cage for chassis stiffness but also my car will be just drag racing.
I imagine the dana is probably between 60-70 pounds difference. If it was Saturday I'd go out and weight my dana. Mine is 46 inch flange to flange so it is lighter by a couple pounds just due to less steel.
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Thanks, 70 lbs for Dana do you happen to know the weight for the 10 pt cage?
 
max512wedge said:
Thanks, 70 lbs for Dana do you happen to know the weight for the 10 pt cage?
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I think my cage is 132 pounds if I remember correctly. It's mild steel 1.625 tubing .
But the added weight I believe is compensated by how the chassis reacts to the power
 
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Big power=Dana. For the structure and added safety of a cage, you should look for other places to reduce weight. It's a good trade-off.
 
Running the stock tank low on fuel is inviting fuel delivery problems. I like to keep my tank 7/8 full.

From practicality standpoint a 6 point bar will get you legal to 10.0 (for now). In my experience it's not that much harder to add the halo and forward bars and is very beneficial to chassis rigidity. If the car is a hotrod just do a S&W 14 point CM kit and be done with it.

If the 512 isn't fast enough hit it with a 250 shot. No more complaints!
 
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Oh and also, your cage will need to be nhra certified 8.50 if you're running anywhere in the 9's or over 135 mph.
Definitely you should read the nhra rulebook for every answer.
 
My '67 Fastback has a Strange S-60, 8 point mild steel roll bar, sub frame connectors, and mild steel front bars welded to the fire wall. (removed inner fenders) 440 with aluminum heads and intake, 727.
I also have a fiberglass hood and trunk lid. Weight with me in it, and 1/2 tank of fuel: 3650 (I weigh 235-240)
 
Translated there is a bunch of difference in safety reqs going below 10s @MOPARMAGA response is very accurate. If you are really going to race a lot become very familiar with the handbook before you start building your car. It affects everything from your rear axle stud length to how the roll bar is constructed, including material. I stay mid tens for that very reason, I simply cannot pass tech to go any faster. I would have to literally gut the car and serious changes to roll bar. I am at best a hobby racer and not at all serious.
 
Sublime one said:
Translated there is a bunch of difference in safety reqs going below 10s @MOPARMAGA response is very accurate. If you are really going to race a lot become very familiar with the handbook before you start building your car. It affects everything from your rear axle stud length to how the roll bar is constructed, including material. I stay mid tens for that very reason, I simply cannot pass tech to go any faster. I would have to literally gut the car and serious changes to roll bar. I am at best a hobby racer and not at all serious.
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Yep, build it around the rule book.
 
A Strange S-60 isn't as heavy as a car or truck Dana, and as mentioned spools save some weight too. There are a lot of places that weight can easily be removed. My Dart is 3292 with me in it race ready, R1 block, 727 and Strange S-60. Glass bolt on hood and front bumper, full interior with all factory glass, it does have Kirkey seats, the radio, heater box and controls and vent boxes and carpet are still in the car too. It has a six point roll bar and frame connectors.

The roll bar, Dana, mini tubs and inboard springs were all done at the same time. The car ran the same numbers as it did before. People focus on the weight of the Dana but forget that it's where you need it.
 
The Dana will hold more HP than the 8 3/4 and the cage will definitely stiffen the car up. The cage will help when launching the car once you get all of the adjustments done with whatever traction set up you are running.
 
the dana 60 from a 67 to 72 ford 1/2 ton pickup is the lighest . compared to 8 3/4 is 35 heavier. a dana 60 is a dana 60. the main housing has different wgts. 1/2 ton ford , then B& C mopars, 3/4 ton pickups, then 1 ton pickups, lighest to heaviest. just foor for thought.
 
I run a stock tank and went from having to run almost 3/4 of a tank of fuel down to 3-4 gallons by running Holley Hydramat. As long as one corner of the mat touches fuel. It will not suck air. I have finished running for the weekend and left the car in the trailer for a week and it won’t start. The fuel SLOWLY drains out of the mat over days. Shake the car and vroom! As long as the fuel gauge moves the slightest bit, I can make a run no issues.

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Jeremiah said:
Running the stock tank low on fuel is inviting fuel delivery problems. I like to keep my tank 7/8 full.

From practicality standpoint a 6 point bar will get you legal to 10.0 (for now). In my experience it's not that much harder to add the halo and forward bars and is very beneficial to chassis rigidity. If the car is a hotrod just do a S&W 14 point CM kit and be done with it.

If the 512 isn's fast enough hit it woth a 250 shot. No more complaints!
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LOL I was planning on that.
 
furrystump said:
I run a stock tank and went from having to run almost 3/4 of a tank of fuel down to 3-4 gallons by running Holley Hydramat. As long as one corner of the mat touches fuel. It will not suck air. I have finished running for the weekend and left the car in the trailer for a week and it won’t start. The fuel SLOWLY drains out of the mat over days. Shake the car and vroom! As long as the fuel gauge moves the slightest bit, I can make a run no issues.

View attachment 1716154494
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That is cool! I would like to covert my Aeromotive 340lph stealth tank to a setup like that. It does fine at the track until 3/8 of a tank. I run it mostly full for ballast (stick car).
 
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