ZD75blue

Hey guys...

A 68 with a small block weighs in at 3,200 and a 75 with a small block weighs in at 3,700... but an 82 with its "standard optioned" block... weighs in at 3,200 again!

One is a little bit safer, a little bit quieter and a little bit cosier then the other.

So... For sure the 82 has:
an aluminum case on the differential
an aluminum rear bumper
steel floors instead of fiberglass
Bucket seats
New bumper setup up front
and a fiberglass rear spring

So with all these changes from the 68 model to the 82 model, what can we "borrow" from the 82 to lighten a 68? The use of aluminum is always nice... in the heads or the intake... or the block for that matter, but I'm thinking stuff that changed thats not drivetrain related!

I think groovyjay has an aluminum bumper on his car... Norval has "cross drilled" his car... I've just pulled the engine and trans and all related systems so mines the lightest of em all! :jester

So, to bring this back on topic... We have a weak front suspension, and a "variable camber" rear suspension, not alot of side impact protection and a relatively flexable frame. Do "we" need to look into some tubular crossmemebers to brace the frame under the floorboards like on an 30's street rod, or triangulate our weak spots to create a stronger package that might be lighter then some alternatives?

Sprung vs unsprung weight... can we rob any lightweight parts off latemodels that will halfway fit? Adjusted mounting points for control arms with circle track tubulars mounted in place of ours?

So, in a quest for a fast car... and one that has the capability to hold its own with the 200k dollar one thats on ebay that twinturbo posted do we rework the design to create a better car? Or follow in there foot steps?

A roll bar maybe with some down tubes up front to make a 6pt would stiffen up the rear suspensions mounting points quite a bit... an under dash bar that ties into the frame up front in the engine compartment would triangulate our frames. A bar running between the front frame horns would add a little more in safety when it comes to head on impacts. The only weak spot would be right beside the drivers knees where it would still be stock, with nothing tieing the frame to the roll bar('s) to leave a way to get into the car, and provide a useable T-top.

Uprading and reinforcing adds weight, new parts ontop of old ones adds weight... So would you use heavy wall chrome moly tubing or thin wall mild steel just to stiffen up the frame?

Cut some weight, add some back all in an attempt to mimic "hydroformed steel" floorpans! Way to much work... :lol:

All I can think of is to use what we already have to work with, make a stronger transmission crossmember that can act as a bolt in frame rail, beef up the attachment points for all suspension devices... Add aluminum body mounts instead of rubber in hopes that the body can add a little more to the package. Up front would engine mounts that use the engine block to tie the frame together as apposed to just holding the gerbil wheel ( :jester ) in one spot so it doesnt pop the hood!

The rear suspension... we've got a bumper bar running across the rear of the frame, a Differential holder and one more to give the kickup something to hold onto. Would a tubular x brace with tabs do a better job of holding the differential? It might be lighter... and it would triangulate the rear of the car... might not work too so dont look at me if the car seperates at the differential at speed! :jester


If we could make things that already are on the car and serve a purpose so they tie into the frame... wheither its a sway bar (I figure a decent size one could be squashed and bolted to the frame... try to work against THIS! :jester

But everything from the rear tire carrier to the vacuum tank up front could be beefed up to provide extra strength without the cost of to much added weight.

Weight reduction could be as simple as cutting the support bracing out of the hood and glassing in a rib around the outside... or running lighter seats like the 12 pound racing buckets.

Stuff that doesnt sacrifice the "comfort" of the car so it cant be a hotrod on the days its not around a track :cheers:

Just my opinions coming up...

If ya look at the brakes, everything is oversized, everthing is extra heavy... they work but maybe there is something else out there that has the same size spindles as ours that runs lighter rotors! Or some aluminum calipers that will bolt right on. Ideally you dont make the car into something you cant get parts for... or cant easily hammer a parts store part to fit :jester

Anyone else have some things to throw in? I'm going to be doing some looking around at other differentials and transmissions to see about cutting some weight there... :cheers:

Shark Racer

Replace the tranny x-member with a tubular one. :)

Aluminum calipers can be purchased from SSBC.

Rally wheels are a lot heavier than some alternatives...

I wouldn't be surprised if the stock radio were a fair amount heavier than a modern aftermarket...

I've also heard that power window setups are slightly lighter than the crank setup.

-Steve

UKPaul

'82 also had an aluminium rear x-member. Tubular transmission x-member from Bowtie is lighter than the stock one.
Cheapest & most effective handling improvment IMHO is to fit a set of lightweight 17" wheels with low profile rubbers.
:cheers:

Jack71

How much weight can you save here. SSBC? Anybody have a link for them?

ZD75blue

How the heck can power be lighter then crank... Oh well :cool:

I was looking at the centerline wheels by autolite for the purpose... that and the shoestring price :yesnod:

ZD75blue

I guess others would be:

No power steering
Lighter alternator... if there is such a beastie
maybe gut the steering colum and run a light weight circle track box... but that would be some work, new steering geometry and all!

Oh and a mini starter... :cheers:

PatsLs1vette

I cant belive the difference in weight on seats.i compared the c3 seats to the c5 seats i just got and a world of difference,theres a weight savings there too.

ZD75blue

Do you have em installed? If not... maybe a bathroom scale :hurray:

phungus

Willwood has some brake calipers that weigh like 2.5lbs each. They're also $100-something each.

Stock seats are definitely heavy, so are stock wheels.

corvettefaq.com has a few good articles on weight savings.

redvetracr

ZD,
I have a fabricated rear end crossmember in my racer, big weight savings but alot of work. You might consider removing all the bracketry behind the bumpers as it`s also very heavy. Unfortunately you will get to a point where lightening your car will get very expensive, like ultra lightweight wheels and aluminum engine parts. You might also look at reducing your "rotating weight" as it actually helps more than reducing "static weight", my trans is all roller bearings inside instead of bushings and the clutch is 5.5" with a cover mounted ring gear, NOT exactly street stuff but you get the idea, I don`t use them but aluminum front hubs are avail also. JUST some food for thought. ...redvetracr

PS: I like the roll bar idea for added stiffness...

ZD75blue

Aluminum hubs...

Man, thats the stuff that makes me wonder! You have 5 nuts to hold the wheel on, you have one big one to hold the hub to the spindle... and ya have 2 ball joints holding the whole thing on! I guess the F1 guys got it right with one big nut to lock the wheel on!

Do ya think an aluminum hub is safe? I mean we use aluminum wheels on most stuff... but the hub? :eek:

Roller bearings in a transmission... I've heard about roller cam bearings, but never in the trans! Can you run one on the street or do they have limited life expectancy? :cool:

shawn_cake

Aluminum rad
Make an aluminum front bumper
Get rid of retractable headlights
Aluminum heads
Aluminum intake
Vette Bakes Performance Plus suspension
Lightweight alloy wheels
Steeroids rack and pinion
Remove air conditioning


I did all of the above to my 1980 and it now weighs 2970 lbs with 1/2 tank fuel.


[Modified by shawn_cake, 10:13 AM 1/9/2004]

groovyjay

Most definately, there's bunch of other bits you can make lighter too. I have fabricated the front cross member and the front bumper supports out of aluminum, yes the rear bumper is also aluminum. I also swapped the halfshafts to carbon fibre and will get a cf driveshaft in the near future. My 20" wheels are alot lighter than my stock 15" ones. The aluminum heads, waterpump, intake also shaved good chunck of weight of the front. IMO the 79 doors are lot heavier than the early shark ones, I know they added side impact bars in them, so now I'm thinking gettting rid of them... :D

HunterRose

Well here's my bid:

C4 suspension, front and back, with new wheels.
Fixed headlights (removes all that vacuum stuff)
Daytona Front end (Gkull saved a bit with his conversion)
Carbon Fiber shafts (GrandSport's using these, I believe)
Aluminum engine stuff (heads, intake, etc).

That should be good for a few pounds. :yesnod:

Excellent thread.

Cheers,

Tony

Twin_Turbo

apart from your list the 82 also had SMC panels, thinner glass.

Althought the alu rear bumper my sound like a lightweight item the thing is actually pretty darn heavy, think holes like norval does :)

UKPaul

Tubular A arms?
shawn_cake, did that lose much weight (the front fibre bumper on my '81 didn't weigh very much at all)??
edit: As Twin Turbo said, that rear bumper is fairly heavy. I didn't weigh either, but the front one felt a lot lighter.

I'd definately 2nd junking the aircon, the box holding all my aircon parts is quite heavy + a bit of hp is also freed up by not having to spin the compressor.

The seats from late models are apparently a lot lighter than earlier ones, but the electric drivers seat weighs far more than the passenger one, so use 2 passenger seats or junk the electric motors, etc from the stock drivers seat. Or just don't fit the passenger seat at all - having no passenger will save a lot of weight :)
For really serious weight reduction, drilling holes in all non-structural brackets (alt supports, seat hinges, etc, etc) helps, as does fitting lightweight or lightened fastners throughout. If you're very rich, or know somebody in the right industry, then getting various brackets made from dural (or titanium) will save a fair bit.
Anybody mentioned mini starters or alternators?
Remove flex plate cover (if auto) & replace with a plastic one.
Replace the 2 stock, heavy horns with lightweight 12v ones from a m/cycle.
Most weight reduction I've done & suggested here is at the front end which will upset the weight balance, so something has to be lost from the rear end. Those hydraulic dampers that support the rear bumper are fairly heavy, is there a lightweight alternative???
:cheers:


[Modified by UKPaul, 12:13 PM 1/9/2004]

ZD75blue

A light weight alternative to the dampers is to not get hit! :jester

I hear ya, I always wonder about em... they only are good for 5mph bumps! :eek:

ZD75blue

So parts you could use off a later model would be the glass... and the door skins? Plus the differential of course.

The rear bumper, does it just bolt on? I havent pulled the skin off of the 75 yet to take a looksy :cheers:

Corey_68

I'm pretty sure no Vette ever came w/ a bench seat, buckets only. :D

ZD75blue

Well... ya have the C1 split bench! :jester