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-   -   Weight Reduction (https://www.rx7club.com/race-car-tech-103/weight-reduction-99526/)

knight1976 07-25-02 07:59 AM

Weight Reduction
 
Looking for any and alll weight reduction sites and ideas. (for a first or second gen)

tims 07-25-02 08:05 AM

remove every thing that is not needed. replace all metal parts with fiberglass or carbon.

knight1976 07-25-02 08:21 AM

I have read and know about all teh "hey i took out my carpet and sounds deadening " posts i want the really crazy stuff that most people dont think about. I posted this in the first gen section but didnt get any websites that have some tutorials or examples of what weight reduction stuff was done to someone elses car. Anyone got any websites like that or a well documented redux project? I saw silkworm pulled a lot out of his car but i know he had a lot of rules to conform to. I just want to dump as much weight as possible, keep the car street legal and not jeapordise the integridty of the car. (So no chop off the top and doors post s guys:)) Any help woud be appreciated. I promise if i get some helpfull info i will documanet this project well and post it up for others to use as a refference.

I am trying ot get a 84 gsl as low as possible.

banzaitoyota 07-25-02 08:23 AM

Get a hole saw and go to town on inner support steel. Of course you risk your structural integrity when you do that. Hole saw the bumper reenforcements

knight1976 07-25-02 08:31 AM

Thats what im talkin about bansai hadnt thought about that (i am only considering the bumper one ). Thanks for the input man!!!

TeamWireRacing 07-25-02 09:34 AM

Pull the interior and lose the 20+ pounds of sound deadener/insulation that is glued to the floor. Use dry ice, break it down into small pieces (it comes in blocks), cover it with plastic and towels and wait. Have a beverage of choice and wait. Come back in an hour or so and bring a hammer! Start removing the plastic in small sections, leaving the rest of it covered. Beat the insulation with a hammer and, in most cases, the stuff will come up in large chunks. Use a chisel on the rest of it, then move on to the next section.

It's not fun, but it's not too hard, either.

knight1976 07-25-02 10:15 AM

Now thats an iteresting idea!! Im gonna have to check that out! THX! but isnt dry ice expensive?

TeamWireRacing 07-25-02 10:55 AM


Originally posted by knight1976
Now thats an iteresting idea!! Im gonna have to check that out! THX! but isnt dry ice expensive?
I bought it from my local ice supplier, just look in the Yellow Pages. It came in 10 lb. blocks and cost $10.95 per block. It's a bargain compared to other ways people use to remove that stuff. I used 40 lbs.

stinkfist 07-25-02 10:59 AM

If your car has a sun roof, you have 40 extra pounds sitting in the worst possable place. You can do what we did on our EP car. Cut the roof off and weld a non sunroof roof on. This is a big job.

You could just weld the sunroof shut and cut all of the bracing out around the sunroof.

Also another technique for removeing the sound deadening is to get a air chisel and go to work. It's faster but you leave all of the metal scratched up. But this doesn't matter if you have the interior painted like we did.

You can remove all of the exhaust heat sheilding too.

remove the body molding. remove all rubber gaskets around the doors and hatch. don't do this if your going to drive in the rain.

Drill holes in the bumper supports.

replace the rear hatch and quarter windows with lexan.

remove dash and wireing harness and build a custom aluminum dash and run new wire harness. this could save you around 40 lbs.


Mike

knight1976 07-25-02 01:15 PM

More helpfull info thanks stink!!! Anybody else got some good stuff or ya holdin out on me???:)

banzaitoyota 07-25-02 01:55 PM

the local dry ice place here has dry ice pellets. .85/lb 15 dollar min order.

Remove all your heat shields
Run .035" wall exhaust tubing SINGLE of course
hole saw the hood reenforcements
light weight seats

macrod01 07-25-02 01:57 PM

Go on a diet. :D

I weight 30lbs less than my brother-in-law and it slightly helps me keep up with him when we race (karts).

I've also seen some overweight guys hopping out of some of the cars at our local events. That extra 50lbs or whatever may not be the difference in winning vs. losing, but its not helping either. :)

1st7heaven 07-25-02 02:41 PM

I spent a week scraping my tar off of the floor boards, then used paint thinner to clean it up, very messy but 23lbs. inlcuding carpet!!!

I just made a mold out my stock hood and had a guy make a fiberglass hood for me....it weighs 9lbs.!!! I am supposed to pick it up this weekend(finally finished it). I should have some pics. of it by the first of next week.

I am also having the head light lids made and the valance between the head light lids. I am first making fiberglass for my race car then carbon for the guys who want extream. There is really no differance in weight in the two.

check out my carbon dash I made(you want to talk about weight savings!!!!).:D

http://members.cardomain.com/7heaven

1st7heaven 07-25-02 02:46 PM

The body weight makes a huge differance!! Not only are you lighter but you can move or react better if you are fit, it really does make differance even in autocrossing!

1st7heaven 07-25-02 03:28 PM

I just remembered also:

stainless header=thinner wall vs. steel header=thicker wall..........stainless header = 7lbs. steel header = 14lbs!!

electric water pump...remove existing unit, install the adapter plate and install electric remote unit...saves approx 3-4 lbs. plus you gain as much as 8hp on the crank hp!!!

knight1976 07-25-02 03:34 PM

Hey 1st7heaven how much does your seven weigh in at? I am very curious as to what type of weight goals i should be looking at. And if you know with and without cage weight that would help a lot too. You arent too far away either i might like to check out your ride or just shoot the sht sometime.

1st7heaven 07-25-02 03:40 PM

I was at 1900lbs, after I am done with this next rebuild I am shooting for 1800 but my class requires 1900 but 1800 would allow me to put the weight where I want it. And yes that is with the cage!

You can come up here and check out my car anytime just PM me for address or phone.

RacerJason 07-25-02 03:45 PM

The biggest weight loss I experienced in building the racecar was in the doors. I took a plasma cutter to both doors lining then did the same with the impact beams inside the doors. The beams alone weighed 20 lbs. each and if you add in the liner, the motor, etc. it adds up super fast. Without the engine I can easily move my car around the garage or driveway with one hand pretty much! Damn light. But obviously unless you have a rollcage that is going into reinforce what you're removing then don't play with safety. I did the whole aluminum dash, sound deadening material removal, sunroof expulsion, tricks also.

knight1976 07-25-02 03:47 PM

Sweet i was hoping to get that low but if thats with a care im sure i can get lower since i do not want to run a cage. Wow now i have a deffinate goal to shoot for.

1st7heaven 07-25-02 04:23 PM

I have also removed the door braces and cut out the inside door panel, removed all motors and regulators....I have all lexan windows. Also, no bumpers under the skins. My fuel tank is gone and I now have a 5 gal fuel cell. This is all great but I dont think it would be practical for street use.

Something else to keep in mind, some guys convert to the GSL-SE suspension(bigger brakes and clipers), this means more weight. In autocrossing we really dont need the big brakes.....I am not sure what the weight differance is between the two.

Another biggy is wheels, I run 16x10s that weigh right at 15lbs each, this is a little heavy. If you run 13s I know you can get 13x9s weighing in at 9lbs.!!!

knight1976 07-25-02 04:44 PM

what model and year did you start out with? And if you had a sunroof how did you del with that? I have located a set of 14x6 that i think are pretty nice. I dont know what they weigh but i think they are aluminum so im not too concerned there.

1st7heaven 07-25-02 05:04 PM

Mine is an 84 GSL that was converted to a SE and then back to GSL. I still have the sunroof, I have not done anything with it yet, when I race, I just take the roof out.

martini 07-25-02 05:19 PM

if you put in a cage, then you can start cutting into more stuff, because the cage will help you retain the rigidity..

but whatever. :)

Buy one of those Summit Racing poly seats. They weigh next to nothing..

RacerJason 07-25-02 06:23 PM

I have an 88 base, that is now far from base :D

My sunroof went out to the curb early in the building process. I just used a piece of fairly thin gauge aluminum and aluminum rivets to fill her in. Some sanctioning bodies require you "delete" any type of sunroof so I thought I'd be better off going this route. Helped having it out while welding the cage up too.

My MOMO Thousand lakes seat weighs in at 10 lbs. if I remember correctly.

1st7Heaven - *nodding my head in agreement* Wheels can make a big difference, its also rotating weight that you eliminate, helps marginally with braking. Panasports seem to be popular with the IT fella's.

finky 07-26-02 01:20 AM

How much weight does acid dipping the chassis take off of an S4? Anything else you can remove under the car?


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