Wieght problems?
 

How much do the Fenders on a 1990 Convertible wiegh and would replacing them with fiberglass mess up the wieght distribution greatly?

The reason I am asking is because I would like to replace my fenders with fiberglass Version Select fiberglass fenders (all four), the stock hood with a carbon fiber OEM turbo II style and replace the front and rear bumpers and add sideskirts with a Silk Automotive URAS body kit and am unsure how much the wieght of the car will shift from front to back and how much I may expect if any.:Wconfused

I can't imagine you'll be saving that much weight by going w/ fiberglass fenders & hood. An aluminum TII hood only weighs 25 lbs, and the fenders should be around the same (they're steel I think?).

So if you save maybe 10 lbs. per item, you'd have 30 lbs. saved. The whole car weighs 3045 lbs, so you're talking about less than a 1% shift.

That is great news! Fiberglass wide body here I come.

now i have a q on his one is that 3045 lbs just the convertable or does my 87 gxl w/ no sunroof or wastefull power windows weigh that much?

There is certainly a weight savings available with a composite hood, but the stock fenders are really light. I doubt there's any weight savings to be had there at all. OTOH, you can lose quite a bit of weight with a performance exhaust if you don't mind the noise.
I've never seen a GXL with no sunroof, but no FC is as heavy as a 'vert. My '86 GXL was rated at 2700lb stock. By the time I was done with it, it was 2400lb and still (more or less) street legal with a (mostly) full interior.

There's a list of all specs for model/year at the top of this section: https://www.rx7club.com/new-member-rx-7-technical-256/specifications-what-did-2nd-generation-rx-7-come-w-options-standard-features-782409/

3045 is the weight of a S5 convertible, which is the heaviest FC.

An '87 GXL manual will weight 2700 lbs. stock.

yeah i looked at that but my car has the tint strip on the windsheild and the auto adjust suspension but no sunroof. im not sure ive been looking at the spec sheets its just not exactly like any of them. so im not sure hwat it was originaly.