Vacuum tank weight?

I'd think someone could relatively easily fabricate an aluminum version of the cast iron piece that connects the steering column to the frame under the windshield. I'd think some thick aluminum plates could be cut to duplicate the shape and then bolted/welded together would make a much lighter functional replacement. The current cast iron piece is gross overkill for strength. For a hobby car, this piece doesn't have to so strong. Even if it broke, there'd be no problem steering the car and driving home. I have a spare cast iron which I bought on the possibility I might take it somewhere to have it duplicated. In the AIM it's called a "bracket," and the part number is 3976457 (1970 AIM, drawing titled Column and Support Asm, UPC 9, Sheet A4)

Similarly the under radiator cross member is a good candidate for an aluminum conversion.

With regards to the above comments, the vacuum tank is pretty light compared to some other parts, especially those parts made in Detroit wonder metal..cast iron
...................

I've bought an aluminum differential crossmember (from a 82). I haven't decided if the weight improvement is worth the fuss and expense of replacing the standard 70 steel differential crossmember. I'd be a lot more motivated to use the 82 alluminum crossmember if Tom would ever get his aluminum differential case to market. His catalog says "sometime in 2009."

For weight improvements for the 70, I have a Keith Black aluminum block (BB), Brodix heads, SSBC aluminum calipers, aluminum MC, composite rear spring. I will be buying an aluminum radiator, aluminum wheels, aluminum AC compressor. Also, the spare tire and carrier has been removed, stock exhaust is removed (will buy Hooker headers). I took a weight hit "upper" by buying a Hydraboost. (sucker is heavy). I have a steel Lakewood scatter shield, but I think I'll go back to the stock aluminum bellhousing..don't plan on any violent shifting (Richmond 5 speed). I plan on keeping the stock AC. The car is a coupe.
 
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One substantial weight savings is to dump your 69 seats in favor of a set from a 81 or 82, they are a very simple swap using your seat tracks and the foot of the 81-82 track, these fit very nicely, better access into the rear area and weigh less than 1/2 as much as the 69 seats, I did this on my 70 and have photo sequence to show what to do.
 
I would NOT dump the Vacuum Reservoir in favor of a small aluminum tank, If you run a lot of CAM you need that large reserve of vacuum to operate the brake booster and the other vacuum systems in these cars, the reserve tank is not very heavy and is one of the secrets to running long duration cams on the street.
 
You don't need a vacuum tank if you go with hydroboost. I want to do the aluminum rear end too. I already have the batwing, so it should be pretty easy.I gotta have a 3.55 or 3.7 in it though.
Bee Jay
 
69427 said:
Bee Jay said:
You don't need a vacuum tank if you go with hydroboost. I want to do the aluminum rear end too. I already have the batwing, so it should be pretty easy.I gotta have a 3.55 or 3.7 in it though.
Bee Jay
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Hydroboost seems the wrong way to go if you're trying to reduce the vehicle weight.
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Use a aluminum M/cyl to make up for it....the superior stopping is well worth it...

wonder why aluminum cast HB units not out there???

:drink:
 
You guys love to over engineer don't you?

I ditched mine, think it was about 48lbs? Then I sold it to JD Corvettes for $100. I run a 239in 245ex @.05 duration cam, with the stock booster and a small reserve where the charcoal canister used to be. Brakes work wonderfully. It should be in gear when you're braking hard anyways, which will make enough vacuum whatever kind of cam you have.
 
mrvette said:
69427 said:
Bee Jay said:
You don't need a vacuum tank if you go with hydroboost. I want to do the aluminum rear end too. I already have the batwing, so it should be pretty easy.I gotta have a 3.55 or 3.7 in it though.
Bee Jay
Click to expand...

Hydroboost seems the wrong way to go if you're trying to reduce the vehicle weight.
Click to expand...

Use a aluminum M/cyl to make up for it....the superior stopping is well worth it...
wonder why aluminum cast HB units not out there???

:drink:
Click to expand...

I already have an aluminum m/c (C5 @ less than a pound weight), and the HB stopping superiority claim is bullshit.
 
Carb Doc said:
One substantial weight savings is to dump your 69 seats in favor of a set from a 81 or 82, they are a very simple swap using your seat tracks and the foot of the 81-82 track, these fit very nicely, better access into the rear area and weigh less than 1/2 as much as the 69 seats, I did this on my 70 and have photo sequence to show what to do.
Click to expand...

I've got a line on some late C3 seats, but don't have any weight measurements on them yet. I'd be interested in your photos. How about starting a new thread about them, along with some details?

thanks
 
The pace car seats are much much lighter than the earlier seats. They are mostly jut the plstic shells and the light hinges on the sides.
 
69427 said:
Carb Doc said:
One substantial weight savings is to dump your 69 seats in favor of a set from a 81 or 82, they are a very simple swap using your seat tracks and the foot of the 81-82 track, these fit very nicely, better access into the rear area and weigh less than 1/2 as much as the 69 seats, I did this on my 70 and have photo sequence to show what to do.
Click to expand...

I've got a line on some late C3 seats, but don't have any weight measurements on them yet. I'd be interested in your photos. How about starting a new thread about them, along with some details?

thanks
Click to expand...

Mike I've been meaning to weight a 79 style seat (pace car) for you and finally got around to doing it today. Complete seat with cushions , carpet on back and tracks weighed 25.5 lbs.
 
DWncchs said:
Mike I've been meaning to weight a 79 style seat (pace car) for you and finally got around to doing it today. Complete seat with cushions , carpet on back and tracks weighed 25.5 lbs.
Click to expand...

Thanks for the info, Roger. I appreciate it.
I'll probably pull the passenger seat out of the car this winter and put it on the scale for comparison.
 
Just what I was thinking

wonder why aluminum cast HB units not out there???

:drink:[/QUOTE]

Gene,
I was thinking the same. A friend Tony has a '73 with a 600 hp rat and a Hydraboost. He let me have a drive a week ago and it's a ripper. The brakes worked so well, I forgot at the time that it had a HB. But afterwards, I thought why hasn't someone made a cast or even billet HB housing? Can't be too hard as it's not that big a unit. Not like a diff centre. Add an aluminum MC and there's a few kg gone. Alternatively, why not use a later model C4 onwards plastic vac. booster and aluminum MC?

I'm looking at using an aluminum MC with an inbuilt prop valve as fitted to late model Holden Commodores and even Ford Falcons. They're made here and are not expensive. That would get rid of the prop valve (???) on the frame under the MC and tidy that area up somewhat. It would also lessen the number of brake lines, fittings and therefore potential leak areas. I'm all for replacing two separate units with one "combined" unit if it's both aesthetically pleasing and functional, as well as cheap.

That's why I'm also going to fit a Borgeson integral steering box in the near future. One of these days, it will be finished and I can get it registered and take it for a drive...............Hmmmmmmmmmmmmmmm.

Regards from Down Under:friends:

aussiejohn
 
Twin_Turbo said:
mrvette said:
wonder why aluminum cast HB units not out there???

:drink:
Click to expand...

Because no one in his diesel dump truck could give a rats ass if the thing weighs a ton.
Click to expand...


Hydroboost seems the wrong way to go if you're trying to reduce the vehicle weight.[/QUOTE]

Use a aluminum M/cyl to make up for it....the superior stopping is well worth it...
wonder why aluminum cast HB units not out there???

:drink:[/QUOTE]

I already have an aluminum m/c (C5 @ less than a pound weight), and the HB stopping superiority claim is bullshit.[/QUOTE]


Well, I mis spoke, not stopping, superior pedal feel and travel charactoristics, that by just superior driveability, make it feel better on the brakes end of things.....

and TT, you right...another 20 lbs on a 8000 lbs truck don't matter a damn....
 
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