Last time I weighed my small block '71 Chevelle 2-dr hdtp, it was about 3530 lbs. The change from 15" ProStars to 17" Salt Flats probably increased the weight a little bit, so maybe I'm in the range of 3550 or so now. Needless to say, she needs to go on a diet. I'm thinking about swapping to fiberglass front fenders, a fiberglass hood, and a fiberglass trunk lid. Do any of you know by experience how much weight I could save by doing this?

Any other good suggestions for weight loss? Low carb gasoline? FYI, I need to maintain a full interior for functionality.

TIA,
Galen

Well, since you just installed 17" wheels you are not likely to be after lightness for drag racing sake. Plenty of suspension options are available to make a 3,500 lb car handle the corners with style.

So, what's really behind your diet quest? Do you have a target weight?

Seriously, upgrading the suspension will benefit handling much more than dropping a couple of hundred pounds.

Thomas

You're right, I'm not out to be the fastest 1/4 mile Chevelle around, but I do still want to improve acceleration significantly while creating a car that handles significantly better than stock.

I'm moving toward an LS-1/6-speed swap to modernize the drivetrain, and I'd really like to reduce the vehicle's weight as much as I can within reason. The LS-1 should reduce the weight a fair amount due to it's all-aluminum construction (I don't know for sure how much, but I'm guessing 100-150 lbs). I'd love to be down in the 3000 lb range, but I don't know if I can truly get it that light while maintaining functionality.

Galen

The production fenders really don't weight much. Things that make a difference - hood (race version), lite wt seats. Lt wt wheels, Competition style 18 ga. headers. If you are really ambicious, you can do what Pontiac did to the 60's drag package Catalina (??). Give the car a swiss cheese frame!!!!

Tube upper and lower A arms
Coilover shocks
Aluminum drive shaft
4 wheel disc brakes
Aluminum Radiator
Aluminum engine parts
Look at parts that do more then cut your weight. Glass parts never really look stright without LOTS of bodywork.

Depending on how you use the car there is weight in things like rear window regulator, replace glass with plex, remove sound proofing, take out the back seats or remove the springs and just upolster a light foam form. If its not driven in the winter remove heating system. Take out the AC and sweat. Remove the wipers, wiper motor, etc and don't drive in the rain. No radio, speakers or boom boxes, listen to the sweat sound of power.

Or do the logical things, add a few HP and handling upgrades and end up with the same results.

Okay, so you want more acceleration and better handling, easy enough - aftermarket to the rescue. Since '71 a lot of neat horsepower and handling parts have been made.

3,530 lbs is hardly a heavy car. One of my friends has a '96 Impala SS that he likes to autocross: 4,200 lbs 'o fun :eek: Best part of all is the number of Corvettes, Camaros, Mustangs, and others that he puts to shame around the cones.

As Dave noted; aftermarket fiberglass body parts are wavy gravy.

Thomas

Anybody have a good weight comparison between a stock hood and a race-weight fiberglass version?

Try thinking in these terms.
A glass hood shaves 15lbs at a cost with paint ect $650. Now your car is 15 lbs lighter and what is that worth in the 1/4?
Now spend $1300 on aluminum cylinder heads. You save 30lbs. You spent twice as much on the heads saved twice the weight. But there is more you added another 25hp and 30lbs more torque.
Put the money on lightweight PERFORMANCE items.

Galen,

Welcome to Team Chevelle. Try a search of this topic in the Performance section. It has been covered several times with allot of good information.

Good Luck.

FYI, disc brakes are heavier than drums.

I'll give the Performance forum a search and see what I can find. Regarding the aluminum heads, I'm already planning on an LS-1 swap (aluminum block, aluminum heads).

Thanks for the info, guys.
Galen

That makes cross drilled drums even better then. :D

I was useing the heads as an example, put the money where it counts. Suspension upgrades will cut weight and improve handling. The cost of tube arms will be close to a glass hood and perform better.

Remove ~25lbs off the front of your vehicle by switching to a lite-weight drycell battery.

Hawker Odyssey #PC680MJT= 15lbs
Factory battery = ~37-40lbs

http://www.batteryweb.com/odyssey.cfm

Emil Dusek:71 SS-502

Yeah, what Emil said. I use a PC680 on my '65 big block, fires up great on a well tuned engine. Darn battery is so small I mounted it on the firewall where the heater used to be. Just start removing everything that you can live without, replace cast iron with aluminum. Replace heavy with light: plastic buckets instead of upholstered factory seats. If you went to 14" wheels you would shave a lot vs the 17's you have. Fiberglass hood, fenders, bumpers, doors. Lexan windows. Do all of that and your '71 could be ~ 2,800 lbs.

Thomas

Get rid of the GM starter! that's a big weight savings.
I've done weight reduction, and mine's about the same as yours.
Alum heads, radiator, rear tubulars, no inners, no sound proofing, no undercoating, no radio,no wipers, heater box will come out, Pro-Stars, M&H rear rubbers/front skinnies.
Next is an alum, water pump. But I'm running out of things before I get to lexan, fiberglass or racing seats.

Originally posted by Bomber '67:
Yeah, what Emil said. I use a PC680 on my '65 big block, fires up great on a well tuned engine. Darn battery is so small I mounted it on the firewall where the heater used to be. Just start removing everything that you can live without, replace cast iron with aluminum. Replace heavy with light: plastic buckets instead of upholstered factory seats. If you went to 14" wheels you would shave a lot vs the 17's you have. Fiberglass hood, fenders, bumpers, doors. Lexan windows. Do all of that and your '71 could be ~ 2,800 lbs.

Thomas Ok guys, maybe I'm missing something, but how can a battery with 280 CCA turn over a stout BBC?

Next question is are they legal at the track? Seems almost too good to be true for $100............

Easy - wetcell, drycell, and gel batteries "dump" their juice differently under an electrical load. The PC680 does not have the reserve capacity of a conventional wetcell, but it has greater current flow under a demand situation - like when cranking an engine over. On the downside: if for some reason you had a hard starting engine it is much easier to run a battery like the PC680 down. If you had a car with greater electrical demands, then a PC680 would be a bad choice.

Also, very much on purpose I mounted the PC680 on my firewall - so that my battery cables are basically ~ two feet long going directly to the starter. Longer battery cables, especially for remote mounted batteries, have a greater current loss based on length alone.

Thomas

Kic

Sorry about the last post...

Kick the 'ol lady out of the car...good for at least ___lbs tongue.gif

Do a search for the step van raditor, replacing the original copper/brass rad with the modern aluminum/plastic is supposed to save 27 lbs, and if you shop around its not even that expensive.

Several guys have done it and its supposed to be a direct bolt in, with no compromises, that I see, other than the effort to install, and that its not free.

Thomas [/qb][/QUOTE]
Next question is are they legal at the track? Seems almost too good to be true for $100............ [/QB][/QUOTE]

Absolutely legal if automotive type
drycell....which Odyssey PC680MJT is.

71SS-502

Thomas/InsuranceGuy,

Thanks for the above info, I appreciate it very much!!

My car will be a race car and limited street car with electrical accessories like a water pump, fuel pump, fan, NOS kit and an MSD digital 7. Battery will also be in the trunk per NHRA rules. These accessories should only be on when the car is running so the alternator will supply most of this stuff. I am thinking for $100.00 it might be worth a shot. Any opinions or should I just go with a standard Optima unit?

If you do go with fiberglass parts take a look at harwood. I bought a 4" cowl from harwood and it was flawless. All I had to do was scuff it and paint it. It is a show series hood so its finished top and bottom. some of my friends have Harwood race weight hoods and they are very nice too, just not finished on the underside. Ive owned fiberglass hoods from two other manufacturers in the past and they were very poor quality. One hood i bought from Unlimited products and it was total junk. It was wavy ,ill fitting, and cracked in 5 places. I since looked at there products at the track on other peoples cars and they all looked shoddy.Glasstech makes pretty nice stuff too. Also when I called unlimited to complain about the quality of their product, they totaly blew me off....the shippig costed more than with Harwood too.