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Wieght Reduction Questions

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Old 05-21-02 | 04:30 AM
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Wieght Reduction Questions

OK Rex Gods....

I have an 89 GXL (not the best model for my project, but oh well). Is it possible to get the dry wieght down to ~2000lbs (the lighter the better).

I am planning on removing the sunroof in lieu of an air scoop, replacing the hood and front fenders with fiberglass or CF. Light rims, no a/c, no p/s, remove the spare tire/jack/tools, would like to keep power locks/windows but will convert if need to. Lexan or acrylic rear windshield. Removing the sound deadening crap from under the carpet, racing seats, harness (will remove the auto seatbelt stuff), no cruise control.

I am thinking about getting the dash molded from CF or fiberglass - as well as door panels - etc (pretty much all of the interior pieces - don't know how I'm gonna pull off a color scheme, but oh well).


Soooo - do ya'll think this weight is obtainable, if so, what else do I need to do ????

Does anyone here have a 2000lb Rex?

PS - I'm not concerened about "creature comforts" - although I am gonna keep a passenger seat in the car.

Thanks,
Jason
Old 05-21-02 | 04:42 AM
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You're basically looking to remove 1/3rd of the car's weight.

Here's what a 1740lb FC looks like.... note that it does not have a drivetrain! A drivetrain will easily put it over 2000.



More info at http://www.mazdatrix.com/faq/epconv.htm
Old 05-21-02 | 05:10 AM
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You want less than 2K# and you still want interior pieces, and some power items? Either start a project with a lighter car of diminish your goal to 2400#~2500# for a car that is not a tube frame that looks like a FC. Sorry to say, but IMO your goal is VERY unobtainable. Find an old Japanese car from the early '80s or sometime in the '70s and work from there. This way you can find a car that will be around 2k# after weight reduction.

jerk_racer@hotmail.com
Old 05-21-02 | 06:06 AM
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Re: Wieght Reduction Questions

Originally posted by Cipher
I have an 89 GXL (not the best model for my project, but oh well). Is it possible to get the dry wieght down to ~2000lbs
Is this another one of theose highschool fantasy projects? Sure sounds like it...
The chassis, running gear and block alone probably come close to 2000lb. Are you talking about making a race car? You don't say that, but that's what you'd end up with. Half the stuff you're talking about (cruise control, power windows/locks) add hardly any weight, yet you mention them like they're important. Carbon fibre guards and bonnet? You must be working with a nice healthy budget. Do you know what "light rims" really cost? Have you removed the stock dash to work out how to replace it with a lightweight version?
If you want a car that's actually practical for regular use, forget all that crazy stuff. Concentrate of the more practical weight reduction methods and making more power. If it is a race car, you should've said so. But I doubt it.
Old 05-21-02 | 06:14 AM
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Well to be fair, he was only askinf IF it was possible, and if so, how.

The answer is a qualified no. If you have to ask how much it will cost, you can't afford it. If you have to ask how to do it, you can't do it.

I'm sure it can be done, but you'd be starting from scratch with a tubeframe and your interior will be basically a seat, a steering wheel, three pedals, and a tach.
Old 05-21-02 | 09:35 AM
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Why would you replace the sunroof with ain airscoop??????

As you've already been told, no. My car is probably down to around 2300lbs, but that's totally gutted, metal cut out of the door, aluminum hood, all non-essential items removed from the engine bay, etc.

PaulC
Old 05-21-02 | 09:46 AM
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My FP car should weigh a little less than Silkworm's. I don't have to have a cage like his and I can remove extra stuff like the headlight assembly's, impact bars(front and rear), the entire sunroof assembly. I can also convert to a carb or aftermarket fuel injection and intake which will cut weight some more. I'm expecting about 2200# maybe a little less with the lexan windshield and hatch but my car will be totally unstreetable with no windows in the doors, no sound insulation or carpet, no dash and a slightly uncomfortable seat for long drives. It can be done but not practical for a street legal/usable car.
Old 05-21-02 | 10:17 AM
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Re: Re: Wieght Reduction Questions

Originally posted by NZConvertible
Is this another one of theose highschool fantasy projects? Sure sounds like it...
The chassis, running gear and block alone probably come close to 2000lb. Are you talking about making a race car? You don't say that, but that's what you'd end up with. Half the stuff you're talking about (cruise control, power windows/locks) add hardly any weight, yet you mention them like they're important. Carbon fibre guards and bonnet? You must be working with a nice healthy budget. Do you know what "light rims" really cost? Have you removed the stock dash to work out how to replace it with a lightweight version?
If you want a car that's actually practical for regular use, forget all that crazy stuff. Concentrate of the more practical weight reduction methods and making more power. If it is a race car, you should've said so. But I doubt it.
Sounds like someone didn't get any last night.....

This is not a high school "fantasy" project. I haven't been in high school in years.

I do have a healthy budget to work with, and yes, I do know how much light tims cost.

Yes, the car is going to be a race car - so don't doubt things you don't know the answer to.

Power windows/locks etc might not weigh alot by tehmselves, but everything collectively does (or am I mistaken here too).

Like I said in my first post, I am not concerned about comforts, just wieght reduction - I think I know where my priorities are at better than you, so don't tell me what is, or is not practical in my case.

And yes, I asked IF it was possible. While it would be nice to obtain my goal, I also understand how much weight I'm actually trying to remove from the car.

So, what, did you look at my post count and ASSUME I don't know much about these cars? I've had my car for about 3 years now and have replaced the engine and made all mods myself. I have been on this forum longer than you (or so I'm willing to bet). That brings me to my next point....

This forum used to be a place where everyone helped everyone else. Now it seems there are alot of "know it alls") that would rather put someone down than help them. Well sir, if you know so much and have the insight on what people's budget is and what is, or is not practical for them you are in the wrong bussiness - I would suggest being a shrink (put all that knowledge to good use - maybe you could actually help peeple that way).

Now, for the rest of you - thanks for the info. 2300-2500# isn't so bad - about halfway between the stock wieght of the car and my "goal". Thanks for your input.

Oh, why would I replace the sunroof with am airscoop - I haven't had a/c for over a year (I live in Houston, Tx - it's hot here). The sunroof does flow some air through the car, but not much. I am looking at the airscoop as a practical add on, not just to change the look of the car. The airscoop will force air into the cab, and allow me to loose a little more weight....

Jason
Old 05-21-02 | 10:58 AM
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well If u look at my car cipher...its my daily driver and thier has been 180 pds weight reduction already. Thats 2850-180=2670 I have a GXL too. I have full interior and anyone who jumps in my car will not tell the difference. my carpet is pulled 30lbs but thin carpet is replaced and large floormats from mazdatrix cover most everything anywayz... I have front and rear bumps gone..that was 40lbs as well as A/C P/S wich was around 50 lbs. I have alum hood 22 lbs and single exaust no cats...probly 40 lbs ...if u get 15 lb racing bat that should save 30 lbs and rear hatch is 30 lbs...dont forget two racing seats wich is 30 lbs saved and take out the sunroof 30lbs. This isnt the least of it but should be an EASY 310 lbs off of 2800 so around 2490 lbs wich is my goal...Nowone will even notice. And I still have my heater yupyyy
Old 05-21-02 | 11:33 AM
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what kind of race car will this bee that you need power windows and door locks? not to be mean just would like to know.

james
Old 05-21-02 | 12:55 PM
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Re: Re: Re: Wieght Reduction Questions

Originally posted by Cipher
Yes, the car is going to be a race car - so don't doubt things you don't know the answer to.

Power windows/locks etc might not weigh alot by tehmselves, but everything collectively does (or am I mistaken here too).

Oh, why would I replace the sunroof with am airscoop - I haven't had a/c for over a year (I live in Houston, Tx - it's hot here). The sunroof does flow some air through the car, but not much. I am looking at the airscoop as a practical add on, not just to change the look of the car. The airscoop will force air into the cab, and allow me to loose a little more weight....

Jason
Jason,

Keep in mind, a scoop like that will duct bugs and water right into your face. Probably not what you had in mind. If it's truly a racecar, then you need to look at your rules book to determine what you can or can't do. For example, my car is allowed to gut pretty much the entire interior, but I have to keep the blasted heater core. WTF!

Anyway, I think the reason NZ is coming down on you is that a car that has been that drastically lightened for racing has absolutely no reason to have windows, let alone power windows (unless you open road race in Nevada), unless the rules say you have to keep them. Likewise with the carpet and the rest of the interior. So you sound more like a kid who wants to have a project car. Honestly, I thought the same thing.

Anyway, good luck with your car, but if I can leave one piece of advice.. If you want to go racing, then go racing. Find a class that suits you, build your car to those rules, and go have fun. But if this is going to be a street car, with street car amenities, then leave it as a street car, with sound deadening and an interior.

Cya

PaulC
Old 05-21-02 | 04:24 PM
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The car is going to be set up to run 1/4 mile. The power windows and locks (like I said, they don't have to stay on the car) I would like ot keep because the car will still be driven on the street - BUT my main focus for the car is the strip. It will not be a "daily driver", but will see alot of street time.

The locks have been disabled (guess I forgot to mention that) because I have door poppers on the car (all of about 1 pound added to the car).

As far as bugs and rain getting into the scoop - I am tinkering with an idea - I am drawing plans up to put an "on/off" switch (if you will) to the scoop. In the "on" position a flap will raise and allow the air into the car - in the "off" position the flap will close, at the same time open a "hole" in the back of the scoop to let the air flow through the scoop somewhat unrestricted. This way I can open the scoop when I want, and when closed I won't have a mini "parachute" on my hands.

I am not worried about street car amenities, just as long as it is "bearable" on the street (and in the rain for those times I want to drive it around and the powers that be have other ideas).

I don't mind people comming down on me, or expressing thier opinions - but I do mind when people THINK they know what I'm after and tell me it's not what I should do. It's my car, my money and my dream. I was just trying to figure out what a reasonably goal would be to set for the car in terms of weight - that way I would know what to put into my sim program to tell me what my "approxamte (msp)" time would be. But yes, the car will be a project car - does that change things for the worst in ya'lls opinion? I like my car and have spent well over 3 times what I bought the car for. I like the way it looks, feels, drives, etc - and I personally want the car to be my foundation for a strip car. But that's just me.

Sorry for ranting - thanks Von.......
Old 05-21-02 | 04:31 PM
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Power windows are slightly less wieght than manual ones
Old 05-21-02 | 04:59 PM
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Oh.

A drag racer.

Ew.



Seriously though, the scoop is a bad idea. better to put a NACA duct in the passenger window and duct air in to cool you, then to put a scoop up there.

PaulC
Old 05-21-02 | 05:16 PM
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Re: Re: Re: Wieght Reduction Questions

Originally posted by Cipher
Sounds like someone didn't get any last night.....
Not last night but the night before...
This forum used to be a place where everyone helped everyone else. Now it seems there are alot of "know it alls") that would rather put someone down than help them.
Sorry if I've upset you, but you're guilty of one of my pet hates on this forum: not giving enough information!. You never said this was going to be a race car. You never gave any indication of budget. This usually rings “high school fantasy project” alarm bells. I even checked your profile for your age but it wasn’t there. Every other time somebody’s asked about a 2000lb FC, it’s been some kid with no clue and no money. Sorry for making an incorrect assumption, but that’s really what it sounded like.
Old 05-21-02 | 05:56 PM
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I liked the guy who wanted to know how to make his FC weigh 1000lb Step 1 - cut car in half...

Uf you're drag racing it and you're worried about weight, probably the FC is not for you then. A better starting point would be an RX-3 or a 1st-gen RX-7, as they are lighter and they don't suffer from independent rear suspension.
Old 05-21-02 | 06:46 PM
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yea get a toyota starlet or something, you can get them under 1500 lbs and drop a rotary in it. my boss at work did and hes got a big *** turbo in it, (5" in and out")
Old 05-21-02 | 07:48 PM
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Re: Re: Re: Re: Wieght Reduction Questions

Originally posted by NZConvertible
Sorry if I've upset you, but you're guilty of one of my pet hates on this forum: not giving enough information!. You never said this was going to be a race car. You never gave any indication of budget. This usually rings “high school fantasy project” alarm bells. I even checked your profile for your age but it wasn’t there. Every other time somebody’s asked about a 2000lb FC, it’s been some kid with no clue and no money. Sorry for making an incorrect assumption, but that’s really what it sounded like.
It's cool, sorry for venting so bad - I had just woke up. BUT it does seem (and this is not directed towards you) the attitudes on this board have gotten worse since I was a regular.

Thanks for all the help...

Jason
Old 05-21-02 | 10:47 PM
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You sound confused to me. Your primary focus is a 1/4 mile car but you want to keep it a bearable street car that has no amenities? Sounds like you want to build a dedicated race car that is streetable. Very hard to do. You'll very likely end up with a unbearable street car with a reinvented sunroof thing on it that isin't much faster than it was before you started, atleast thats the way I see it.

And before you acuse me of needing to get laid I enjoyed my wifes company this morning before work

Seriously thou, build a street car or a drag car. You'll be happier in the long run. I learned the hard way to be competitive you need a dedicated car.
Old 05-22-02 | 01:01 AM
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My car weighs 2533lbs. w/no spare tire, no pass. seat and 1/4 tank of gas. That's w/o me in it.
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