The project car is an '88 SE. Building the car for SCCA Rallycross. I need to keep the windows in the car(for dirt issues). Where are the most significant weight savings found on these? I know I'm already gonna drop the whole exhaust and run a straight pipe out the back.... what else?

This pig is too heavy!!!!!!

Dan

 

Whatcha got into now, Dan?

There's a lot of interior that should get you down to around 2500 lbs. There's a lotta extra weight in these FC's though.

 

Hey!

I inherited an FC that has been a rallycross car for the past two seasons... Woot!!!

 

and run a straight pipe out the back.??? out the side save 20 lbs. and lexan will save you 100 lbs. + or -

 

Replace the rear hatch glass with lexan as suggested above is a good weight saving measure, beyond the obvious strip the interior. The seats are probably 30-40lbs (I weighed mine once, but don't remember), so a lightweight racing seat can save some significant poundage. The aluminum hood off a turbo or 'vert (check though, the odd one isn't aluminum) saves ~15lbs. A smaller battery can easily shave 10-20 lbs (depends on how small you want to chance). Rims are often overlooked: I have a set of 15x6.5 vert rims, 11lbs, saves about 3lbs per rim over the already light factory 5 spoke 15x6 rims my '91 came with. A lot of aftermarket rims will be 17-18lbs for a 15x6, and up from there as diameter and width increase. Weight savings on the wheels helps both handling by reducing unsprung weight, and acceleration by removing rotating mass - I noticed even the 3lb/rim saving going from the factory to the vert BBS rims - felt much the same as a lightened flywheel.

 

Well obvious things such as un needed interior. Spare tire/jack. Lexan parts or carbon fiber parts. Wheels are easily overlooked as mentioned. Heat shields, anything small you can find will add up eventually

 

you can get rid of a lot of stuff in the engine bay too.

AC
P/S
emissions stuff
exhaust manifold (replace with a nice racing beat header )
relocate the battery
cruise control

you can also take out the bumper supports for rallycross they're nice and heavy, You shouldn't really be hitting anything (hopefully)

seats are also a big one, and that rear glass weighs a billion lbs.

 

there is also the stereo too.

 

Windshield wipers, front & rear, antenna motor, blower motor, all that under dash ducting, pop up headlights, heat shielding around the fuel tank, sunroof assembly(just put a piece of lexan up there to cover the hole), lightweight gas cap

 

Come down to Pele's house. We can lighten it up.

 

You might be able to get away with removing some of the electronics from the instrument cluster. They're surprisingly heavy. Like the indicator switch. You can take out the wiper switch too, but you may need that in rally. Or swap over to a different switch like an on/off switch if that will work.

 

All good ideas guys, except wheels.... Rallycross= wheel bashing!!!!!

 

You can also get a fiberglass hatch frame to go with the lexan 'glass'. If I remember correctly, it's a decent chunk of weight.

 

remove the popup head lights and replace with driving lights and plexi glass.

 

Remove the sound deadening if it hasn't been removed yet. Should make you lose about 30lbs. Dry ice is your friend

 

Strip everything you don't absolutely need out of the interior. That includes all carpet, sound deadening, any seats that won't be used, etc (if you have power windows, replace with manual windows if you need teh windows to be functional). Then, start stripping things out of the engine bay, like A/C, power steering, etc. Then, replace that rear hatch with a lexan hatch, that will get rid of a lot of weight. And an aluminum hood will knock off some weight too (IIRC, verts had aluminum hoods).
That should be a pretty good start.

 

Get a hole saw and lighten up the chassis

 

Depending on the rules I have a fiberglass hood that fills in the headlight area, it weighs about 15-17 lbs. I also make the fiberglass rear hatch w/ lexan that ends up at 15 lbs. between those two parts you can take just over 100 lbs out of the car. (removing the headlight junk).

There are a few other things like door bars, 11.5lbs each. Use a smaller battery, you will be suprised just how small you can get away with. Probably can save 30lbs on battery alone.

 

Gut the doors, I find they're super heavy. Must have a lot of weight in there.

 

If you want to go all out theres Doors/fenders/hatches that are all carbon fiber... cant remember the site though....

 

FC doors make my dad's 77 MGB doors seem light

 

all the obvious things listed above..

its actually beneficial to get under the car, and actually strip off all the **** and dirt stuck to the bottom, as well as all the heat shielding and such..

if you really want to get into it, fabricate lightweight subframes front and rear, you could probably save a good 50 pounds.

obviously if you see almost anything other than metal in your interior then you have weight to save.

composites and fiberglass panels will get things light. if you wanted to get into molding your own parts, you could make a mold of the entire front end as a whole, and just have it flip forward. you could save a bunch of weight like that.

cut out the floor, replace it with a steel tube fame, with riveted honeycome aluminum panels. they are extremely light for their rigidity, and you will see a pretty big improvement from that.
this would also add some structual benefits if it is tied into a roll cage, im not sure if you'll be using one... if you are using one, extend it through the firewall, attaching to all the suspension points, and cut off everything else. you'll see some weight there.

for any tubing used in any of the above, use 4130 steel, it is stronger for its weight.

i think thats about all i can think of right now

 

Cut the floors, use moving blankits with Fiberglas in it. It will harden up just like steel and never rust...

 

1st of all, everything above, that everyone so far suggested is good. If you search the internet you will find a company that makes fiberglass door panels , hoods and , if I'm not mistaken, even a rear hatch panel for the Fcs. Mean while look at these pics:

 

A couple of more picts: