Weight reduction: Running out of ideas.

Z bar in 6061 sounds reasonable. A little (very little) more deflection because of the lower modulus of elasticity but strength is similar to mild steel original. Might sleeve the linkage bar bearing surfaces with a sacrificial bronze insert (like shift levers) where the link bars attach. Don't think fatigue is a concern with current low use of car. IIRC the captured stud is held in place with a wire ring clip in a groove - replicate the OE pocket and reuse the stock ball stud and seats.

We're pretty much on the same wavelength here. I had envisioned putting bushings in the linkage arms and also one in the tube where it rotates on the ball stud on the engine block. The captured stud still has me thinking, as I'm not convinced yet that I'm talented enough to be able to fabricate the groove needed for the snap ring. I still have a bit of time to figure out how to "duplicate" that while I'm looking for the tube material (my favorite local metal place didn't have what I was looking for the other day).

I agree that fatigue shouldn't be a major issue if I correctly size things (I did do a bunch of torsional strength calculations to amuse myself the other week during down times at an extended family gathering). The clutch linkage doesn't get that much day to day use, and I'm curious (as I'm not a mechanical engineer) if the fact that the bar arms (and each finite area of the arms) are only stressed in one direction (just one half of a cycle, not a complete, reversing cycle) reduces the effects of any cycling. I welcome correction or clarification from any metals experts here.
 
I'm out of the country so I can't make any measurements but much of the force multiplication will occur at the clutch fork. The pedal ratio is somewhere about 7:1 so I figure about 50# force at pedal and 350# applied to z bar lever arm. The Zbar lever arm is somewhere around 6" so I'd guess about 175 Lb-ft torque applied to the tube. Fatigue test machines do full reversal but with low cycles you should have no problems. I don't have any reference material here. I flew in a 1943 DC3 a few weeks ago so aluminum should be OK.

You should be able to grind or have ground a profile on a boring bar that matches the OE clip ring groove. IIRC there are plastic bearing cups for the ball studs.
 
I kno wyou are looking for ways to reduce the weight of your car but have you done anything with the gas tank? I know with my 79 the tank sits on top of the frame and believe this is the same for your car also. Lowering the tank to be flush with the top of the frame would help your center of gravity and allow you to carry more speed through the turns.
 
I kno wyou are looking for ways to reduce the weight of your car but have you done anything with the gas tank? I know with my 79 the tank sits on top of the frame and believe this is the same for your car also. Lowering the tank to be flush with the top of the frame would help your center of gravity and allow you to carry more speed through the turns.

Yeah, I've been trying to figure out my options with the fuel tank. I'm running stock location rear mufflers, so that gums up the works when trying to lower the fuel tank. So far the only decent option I've figured out is to fabricate a custom tank of about 8-10 gallon capacity versus the stock tank capacity (16-18 gallon range IIRC). The next thing I haven't figured out yet is if it would be better to make the smaller tank full height but narrow, and place it over to the right side to help get weight off the left side, or make the tank full width but shorter height to drop the c/g of the tank downward.

That's where I'm at currently. I appreciate your input here. :thumbs:

OBTW, anyone here know the weight of the early C3 fuel tanks?
 
I kno wyou are looking for ways to reduce the weight of your car but have you done anything with the gas tank? I know with my 79 the tank sits on top of the frame and believe this is the same for your car also. Lowering the tank to be flush with the top of the frame would help your center of gravity and allow you to carry more speed through the turns.

Yeah, I've been trying to figure out my options with the fuel tank. I'm running stock location rear mufflers, so that gums up the works when trying to lower the fuel tank. So far the only decent option I've figured out is to fabricate a custom tank of about 8-10 gallon capacity versus the stock tank capacity (16-18 gallon range IIRC). The next thing I haven't figured out yet is if it would be better to make the smaller tank full height but narrow, and place it over to the right side to help get weight off the left side, or make the tank full width but shorter height to drop the c/g of the tank downward.

That's where I'm at currently. I appreciate your input here. :thumbs:

OBTW, anyone here know the weight of the early C3 fuel tanks?

Build your own that sits flush with the top of the frame, doesnt drop to hit the mufflers but still drops in the center shaped like a T
 
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Look into the Ford style battery terminals... they are stamped sheet metal verses the common LEAD (!!!) style
https://goo.gl/images/iV3QzC


Another thing that occurred to me today is that Custom Image Corvettes reproduces the lower grille "hokey sticks" in fiberglass instead of pot metal... some chrome vinyl wrap would have most people fooled that they are not actually chromed. They also sell the bumpers in 'glass but I'm not quite convinced I want to remove the metal bumpers yet...

I apologize that I somehow missed this post. CIC is in my home town, and I've stopped in there a couple times to see their operation. I'll pull one of those front grill trim pieces off and get a weight on it. I'm guessing those replacement pieces aren't cheap, but the compensating factor is that trim piece weight is way the hell up front.

Regarding the battery terminals, fortunately my cheap lawnmower battery just requires some small eyelets on the ends of the cables, so I'm about as light as I can go there.
 
It seems like these have been out for a few years now, but this is the first Im hearing of it... Ididit Steering has a 6lb collapsible column with turn signals and hazards, and it looks relatively stock. The only kicker is that it doesnt look like it has an ignition switch (for those of us that are '69+), and its currently only available in 30" lengths (C3 vette is 36") I deleted my ignition switch so thats no issue, but Im going to send in a quote request for a custom ~35"

https://www.ididitinc.com/c-1331677-performance-columns-pro-lite.html
 
It seems like these have been out for a few years now, but this is the first Im hearing of it... Ididit Steering has a 6lb collapsible column with turn signals and hazards, and it looks relatively stock. The only kicker is that it doesnt look like it has an ignition switch (for those of us that are '69+), and its currently only available in 30" lengths (C3 vette is 36") I deleted my ignition switch so thats no issue, but Im going to send in a quote request for a custom ~35"

https://www.ididitinc.com/c-1331677-performance-columns-pro-lite.html

My non-tilt column with the steering wheel/hub, steel u-joint and ignition switch deleted weighs 21lbs... Hoping by the time I have this pro-lite column extended, quick release hub and steering wheel I can be ~10lbs lighter
 
Lithium battery

I've heard a lot of good things about the Battery Tender/Deltran lithium batteries. I think I'm going to order their 4# 480 CCA model. That will be 12# lighter than my current 16# garden tractor battery.

It ain't weight off the front, but it's still mass that won't have to be accelerated or decelerated anymore.
 
Always looking to help you spend money$$$.:eek:

I was "on the hunt" for a mechanism for the gull-wings, and came across these:

https://picclick.com/C3-Corvette-68-82-Electric-headlight-motor-conversion-kit-321689148631.html

I'd post a pic - but my page is full and won't take anymore!

With an electric motor conversion (sorry more amps for the new battery) you could dump the vacuum tube behind the rear bumper and all the associated apparatus. Ought to be worth a few pounds. I seem to recall the tube was maybe over 30 pounds!
Somewhere around $25 per pound there...:idea:

Cheers - Jim
 
Always looking to help you spend money$$$.:eek:

I was "on the hunt" for a mechanism for the gull-wings, and came across these:

https://picclick.com/C3-Corvette-68-82-Electric-headlight-motor-conversion-kit-321689148631.html

I'd post a pic - but my page is full and won't take anymore!

With an electric motor conversion (sorry more amps for the new battery) you could dump the vacuum tube behind the rear bumper and all the associated apparatus. Ought to be worth a few pounds. I seem to recall the tube was maybe over 30 pounds!
Somewhere around $25 per pound there...:idea:

Cheers - Jim

Vacuum tube behind the rear bumper???
 
That huge tube behind the front --oops maybe only on the rubber bumper cars?
On my '78 it had a fitting that tied to the headlights - so my assumption was vacuum receiver.
12694e6c8214b8cda.jpg
Maybe not. Anyway on my car --its gone!

Cheers - Jim
 
the tube is only on rubber bumper cars... '69s had a steel vacuum tank in the drivers fender... Which leads me to think it could be replaced with a junkyard-found plastic one from a newer car
 
the tube is only on rubber bumper cars... '69s had a steel vacuum tank in the drivers fender... Which leads me to think it could be replaced with a junkyard-found plastic one from a newer car

I agree. While I had things apart swapping out the pb booster for the lighter C4 piece, I took the vacuum tank out. IIRC it was about five pounds. Haven't taken the time to look for a replacement tank yet.
 
That huge tube behind the front --oops maybe only on the rubber bumper cars?
On my '78 it had a fitting that tied to the headlights - so my assumption was vacuum receiver.
12694e6c8214b8cda.jpg
Maybe not. Anyway on my car --its gone!

Cheers - Jim

Isn't this part of the bumper for these cars?
 
I didn't look at the chassis manual when I pulled it years ago. If you want the 5mph "safety" prescribed by the fed, it might have some utility. Mine is a track and sometime street (when finished) and therefore not "required." And, with major front chassis/body mods, not "needed."

Your mileage may vary.

Cheers - Jim
 
I didn't look at the chassis manual when I pulled it years ago. If you want the 5mph "safety" prescribed by the fed, it might have some utility. Mine is a track and sometime street (when finished) and therefore not "required." And, with major front chassis/body mods, not "needed."

Your mileage may vary.

Cheers - Jim


I thought it was welded into the frame.
 
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