Weight reduction: Running out of ideas.

Take a good look at the stack of shims under the Door hinges . I made one out of a piece of 1/4 " thick steel and then I got really anal and drilled it full of holes . I mean really full of holes and chamfered each one . When I was done it was easilly as light as Aluminum.

Also did the C5 master cylinder and Booster , and while I was at it dropped the steering column and replaced that heavy cast Iron support with the later stamped piece.
 
Take a good look at the stack of shims under the Door hinges . I made one out of a piece of 1/4 " thick steel and then I got really anal and drilled it full of holes . I mean really full of holes and chamfered each one . When I was done it was easilly as light as Aluminum.

Also did the C5 master cylinder and Booster , and while I was at it dropped the steering column and replaced that heavy cast Iron support with the later stamped piece.

We're on the same page here. :thumbs:
I swapped out to the C5 master cylinder, and also bought a C5 booster, but it's still on the shelf at the moment. IIRC there's about a four ounce difference between a C3 and a C5 booster.
Replaced the steering column support last year. Big ugly chunk of cast iron.
Been eying the hinge shims. There's about 3/8" of shims in one of the driver's side hinges. I've been looking to make an aluminum replacement for them one of these days. IIRC it looks like a PITA to get to the hinge bolts, though.
 
ditch the radio... it's a boat anchor :eek:

what about that carpet and those seats? :twitch:

:beer::beer::beer:
 
Take a good look at the stack of shims under the Door hinges . I made one out of a piece of 1/4 " thick steel and then I got really anal and drilled it full of holes . I mean really full of holes and chamfered each one . When I was done it was easilly as light as Aluminum.

Also did the C5 master cylinder and Booster , and while I was at it dropped the steering column and replaced that heavy cast Iron support with the later stamped piece.

We're on the same page here. :thumbs:
I swapped out to the C5 master cylinder, and also bought a C5 booster, but it's still on the shelf at the moment. IIRC there's about a four ounce difference between a C3 and a C5 booster.
Replaced the steering column support last year. Big ugly chunk of cast iron.
Been eying the hinge shims. There's about 3/8" of shims in one of the driver's side hinges. I've been looking to make an aluminum replacement for them one of these days. IIRC it looks like a PITA to get to the hinge bolts, though.

remove threshold, and kick panel, there are the bolts on the bottom, but top requires removing dash panels....PIA for sure.....which is why my dash panel is on a plug for the lights, and tach is electronic with it's own plug, and the ONE ground lead......did all that years ago, on account of being lazy....

:thankyou:
 
The C5 booster was one of the easiest mods yet ! Bolt patern exactly the same , just have to shorten the rod and add a clevis. The rod was sized perfectly to cut 3/8 fine threads . Also have to make the center hole bigger on the car, might be another ounce there. Change the tube nuts on the Brake lines and bleed, thats it.
 
ditch the radio... it's a boat anchor :eek: The radio is coming out eventually for repair. I first need to figure out an acceptable blockoff plate.

what about that carpet and those seats? :twitch:

:beer::beer::beer:

Gotta have carpet, it's a street car. And the seats are lighter late model '79 seats (about 30# total lighter than the '69 seats).

All the cars I run with on track days are newer (and more expensive) street cars. All with full interiors. Just trying to play by the same informal "rules".
 
Got the aluminum exhaust box finished and installed. Nine pounds less than the steel box (6# versus 15#). Looking to run a couple track days in the next couple weeks, so I suppose I'll find out if there's any durability issues with this thing.
After the track days are finished I'll get the 4" S pipe built which should take two more pounds off the exhaust.
 
May have found a quick 5# to loose (maybe 4+/-). I'll take a pic and post tomorrow.
It involves cutting away a section of the birdcage - under the door sill. There's still plenty of material and the fore and aft body mounts should keep everything in alignment and stable.
I've cut mine to let me remove the birdcage from the chassis/roll cage so I can get in there to paint, wire, add fuel and brake lines.
It may be a problem if you want to keep the stock floor though. But, I'll shoot a pic anyway.

Cheers - Jim
 
Looks like all the easy stuff is done , now it gets harder. How about the Bolts ? there is probably 100 or so bolts that are too long , anything sticking out past the nut is un-necessary . Allen heads usually weigh less than hex head. How about polishing the large castings? Not only are You makin it look perty , but You are removing metal and that = less weight.

I removed a couple of pounds from My Intake by removing un-necessary webbing between the runners , bumps and unused bolt bosses , along with polish and port inside and outside polish. Time to fire up the Drill Press You will be surprised how much it can remove. Stan

Remember lots ounces will add up to be Pounds.
 
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Ran over to Topeka for a track day yesterday. Hadn't been there since May due to a lot of family business keeping me on the road quite often, and the LR wheel bearing replacement last month. Put the car on the scales during Tech, and got 2815#. This was with 1/8 tank of fuel, no middle belly pans (didn't have time to put them back on after modifying the exhaust box), and I temporarily removed the passenger seat (20#) to install a second fire extinguisher in that spot on track days. Background: I had a development C4 car catch fire on me several years ago while on the test track, scaring the hell out of me, and I just like having a bit more extinguisher capacity when possible.

IM002442_zps7d2a9059.jpg

Once again, I had the oldest car on the track. There was a C7 running also, but he was running in the novice group so I didn't get to see how that car would run with an experienced driver. There was also a Ford GT(40) there on Hoosier tires, but I was able to run away from him. I assume there was just more car than driving ability there, to explain that circumstance.
 
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Did you install an alum block bb? I thought you posted photos of one.
 
What brand did you get?

I see on some crate engines it is a $2k upgrade, but that would be bill Mitchell. Dart would probably be more.
 
Got the aluminum exhaust box finished and installed. Nine pounds less than the steel box (6# versus 15#). Looking to run a couple track days in the next couple weeks, so I suppose I'll find out if there's any durability issues with this thing.
After the track days are finished I'll get the 4" S pipe built which should take two more pounds off the exhaust.

I noticed at the track last Wednesday that the aluminum box is a little louder than the steel box. I think I'll cut it open a bit and add a couple more internal stiffening ribs, and possibly double wall the top and bottom. They're currently .070" (IIRC, as I didn't have any big size 1/8" sheet), and it won't cost me much weight to add the second layer.
I also need to tap and weld an aluminum piece to screw an O2 sensor into this box. I appreciate the help from a previous thread on what tap size is required for this (18mm x 1.5).
 
Well, I added another stiffening rib inside the exhaust termination box (tieing the top and bottom surfaces), and welded several (ten, IIRC) two inch wide straps on the upper and lower surfaces to tie the internal rib nodes to the outer (left and right) surfaces. Added about a pound of material. Quieted the tinny sound a bit, but still not good enough. The sound in back out of the mufflers is quite quiet and acceptable, but inside the car the termination box just sounds like I'm sitting on top of one of those (I apologize if I'm insulting anyone) bullshit flowmaster mufflers. While I like the concept of a couple more horsepower with a termination box, I need to make a decision on putting the heavier steel one back on, or just replacing the aluminum box with an aluminum Y-pipe (dual 3" into single 4"). I'm leaning toward doing the Y-pipe as I'm already planning on replacing the section of exhaust from the muffler inlets forward to the present exhaust box 4" outlet with aluminum tubing. I ought to be able to take another 5-8 pounds off the exhaust with this change.
 
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