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Thread: 280Z weight reduction

  1. #1
    Join Date
    Feb 2010
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    LYNCHBURG VA
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    26

    Default 280Z weight reduction

    My 280z rolls across the scales at 2700 lbs, I am no featherweight at 213 lbs. any body have an idea of how to get weight out of the car ? some Ideas are the following:

    1) run less gas. I have a 12 gal cell have been working on a sumb with flappers to get the fuel load down to 7 gals or so

    2) lighter exhaust, el cheapo 16 ga 3" exhaust weighs a bit, I have been thinking about a nice 2 1/2" .049" wall with a super light muffler

    3) remove undercoating. not sure what it is worth but has to weigh something ? bought a " crud thug" tool but I have not tried it yet

    any other ideas ? I know the weight has to be killing me, but I don't see how I will ever get there

    Thanks

  2. #2
    Join Date
    Jul 2004
    Location
    Raleigh NC
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    I'm not too much different from you in that I am coming in heavy with no real way to drop 50 lbs.

    A few off the cuff while eating that I'm sure you've done but what the heck.

    1. Did the car have AC? Have you removed the AC controls, evaporator, and anything AC related? I personally wouldn't care if you gutted all that stuff as min weight is min weight, but I don't know about the other guys.

    2. Shop batteries. Take your scale. You'll find significant weight in the same group batter across different lines/store brands. Get the lightest one.

    4. Stock fuel system stuff, you've got a cell, you don't need to have that mess.

    5. One fuel pump? I have double redundant pumps, filters, etc. and will be dropping the redundancy.

    6. NASCAR bars so you can gut those doors? I did that on my passenger side last year.

    7. Ally window net rod.

    8. Light seat.

    9. What kind of radiator do you have? I have a really light ally piece, about 1/2 the weight of a stocker if not more.

    10. NISMO starters weigh 2.5 lbs more than the el cheapo brand from Advance Auto.

  3. #3
    Join Date
    Nov 2005
    Location
    Rocket City, Alabama
    Posts
    607

    Default

    Everything Ron said, plus the undercoating. What wheels are you running. Significant weight can be lost there if you have heavy wheels. Replacement windshield might be significantly lighter, or so I heard
    Paul Ballance
    Tennessee Valley Region (yeah it's in Alabama)
    ITS '72
    1972 240Z
    "Experience is what you get when you're expecting something else." unknown

  4. #4
    Join Date
    Dec 2005
    Location
    Port St. Lucie, FL
    Posts
    354

    Default

    Quote Originally Posted by Ron Earp View Post

    4. Stock fuel system stuff, you've got a cell, you don't need to have that mess.
    When we re-did our shell I was suprised how much just the hard fuel lines weighed. It was a couple of lbs. Ron's list has some great suggestions (a few I'd never heard), and Paul is right about the undercoating and wheels (we are still VERY heavy here at 17 lbs.wheel). Undercoating should be several lbs. One thing not mentioned is gutting the door IF you add nascar bars to your cage. You add a little weight back on with a bit more cage, but if I remember correctly we saved around 17lbs a door when we put in the nascar bars. The biggest thing is to look at EVERY aspect of the car in the most minute detail possible. It all will add up.



    Edit: Somehow I missed Rom mentioning the nascar bars in his post. I guess I didn't look in the most minute detail possible.
    Last edited by spawpoet; 02-15-2010 at 08:29 PM.
    Chris Carey

    Central Florida Region
    ITS/Vintage Datsun 240Z

    Favorite tool to remove undercoating---- A curb!

    "Understeer is when you hit the wall with the front of the car and oversteer is when you hit the wall with the rear of the car.
    Horsepower is how fast you hit the wall, torque is how far you take the wall with you."

  5. #5
    Join Date
    May 2001
    Location
    IT.com "First Loser" Greensboro, NC USA
    Posts
    8,607

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    Pay attention to everything you add. I see a lot of brackets (e.g., for kill switches) that are way too heavy. Dash panels, etc., etc., etc. Lots of little pieces add up and if you are doing them as you go, they don't cost much to make lighter than you might.

    We got about 30 pounds of undercoating off of the Golf when we built it. I don't know how a Z compares but the Thug is the right tool for the job. I found a pair of old shoes when we moved this last time, that STILL had crumbs in them...

    K

  6. #6
    Join Date
    Mar 2002
    Location
    Black Rock, Ct
    Posts
    9,594

    Default

    In addition to the good suggestions above:

    Fasteners are free, some folks use other materials that are lighter. Of course, optional things like radiators needn't be held in with 6 stock bolts, two small tabs and two small bolts will do. That's just and example.

    Suspension rules are pretty open. does the car run struts? those are pretty open, and significant weight can be saved there, Look at the inserts too. Swaybars. Big savings possible here. Hollow bars, with alum arms.

    Stock systems that are optional. Everything goes. (although I don't buy into the 'remove the heater core because it's attached to some housing that the AC air ran through' mentallity). Anything that is open for removel, remove. Anything that is optional, (mirrors) consider weight when replacing.

    Tires. They don't all weigh the same, and their weight 'costs' more as it's rotating and unsprung.

    Exhaust. Stainless and or titanium. Significant potential for loss, and it can last longer.

    On the Nascar door bars, read the rule carefully. Your right side should be the bare minimum to meet the exact words of the rule. (example: When they say "project into the door opening" they don't say by how much...you don't need the crush space, so 1/8" projection with ONE bar is enough to satisfy the rule requirement, IIRC. )

    Seat. Buy smart and save 7-pounds or so.

    Clutch and PP ...there are some savings available there, and again, thats rotating weight.

    Guages. Remove all stock ones, replace with small dash panel and data aq system. Saves a bit of weight, but gives you a record of things you might be missing on track. (An oil pressure fluctuation in left handers that could rear it's head later, or a voltage fluctuation that explains that weird miss) AND you can review your driving which always makes you faster._

    Sorry about this one, but eat more fruits, salads and exercise regularly. Or more. Helps during a three hour stint too.

    Finally, read the rulebook, start to finish and think about weight in regards to every line.
    Jake Gulick


    CarriageHouse Motorsports
    for sale: 2003 Audi A4 Quattro, clean, serviced, dark green, auto, sunroof, tan leather with 75K miles.
    IT-7 #57 RX-7 race car
    Porsche 1973 911E street/fun car
    BMW 2003 M3 cab, sun car.
    GMC Sierra Tow Vehicle
    New England Region
    lateapex911(at)gmail(dot)com


  7. #7

    Default

    Another thing are all the brackets in the engin compartment for the air canister and other junk. buy a drill to remove them (spot weld drill?). Depending which year you have some of the bumper mountint points were much beefer and an area to look at removing/lightning. Ron was right about the dash the 280s were a lot heaver than the 240s if possible pull it and gut it they had a lot more material and braces inside and if the dash is out remove some of the mounting brackets for the ac and other interior parts you are removing (drill again). And like everyone said the undercoating. When we built our IT 240 we weighed the undercoating from the floor pans and interior got 12lbs out.

  8. #8
    Join Date
    Jan 2007
    Posts
    161

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    A huge aluminum radiator saved over 10 lbs for me. Nascar door bars saved 24 lbs on the right side. Speedway tubular sway bar was over 10. Ron's light weight crank pulley was 2.5. Read the cage rules again for minimum size and wall thickness on non required bars. Seat mount can be very heavy if you are not careful. also other things like cools suits, mounts for coolers and drink bottles. Replace your airbox/air cleaner housing with fiberglass. Steel is about 2lbs per square foot, aluminum is about 1, glass can be under 0.5, and 0.25 if you really do it right with vacuum bagging.

    Taking weight out of the driver might sound easy for you little guys, but trust me it is not as easy to take it off as to put it on!!!

    Mike

  9. #9
    Join Date
    Mar 2001
    Location
    Acworth, GA USA
    Posts
    455

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    Aftermarket windshields often weigh much less than the old factory windshield, and it's high up weight which is double good to remove.

    Also, focus not just on weight removal but where the remaining weight is. Move everything you're allowed to move. Example: our Jacobs ignition box was on the passenger footwell rocker beam.

    Plus what everybody else said.
    katman

  10. #10
    Join Date
    Jan 2001
    Location
    Buffalo, New York
    Posts
    2,942

    Default

    Oil Cooler lines/ accusump?

    Oil is heavy

  11. #11
    Join Date
    Oct 2002
    Location
    Concord, NH 03301
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    700

    Default

    Another thing are all the brackets in the engin compartment for the air canister and other junk. buy a drill to remove them (spot weld drill?). Depending which year you have some of the bumper mountint points were much beefer and an area to look at removing/lightning. Ron was right about the dash the 280s were a lot heaver than the 240s if possible pull it and gut it they had a lot more material and braces inside and if the dash is out remove some of the mounting brackets for the ac and other interior parts you are removing (drill again). And like everyone said the undercoating. When we built our IT 240 we weighed the undercoating from the floor pans and interior got 12lbs out.
    Yikes, be careful how far you go w/ removing things that require the spot weld drill to remove. The emissions stuff can go, but its mount is not listed as optional. For example the fog lights mount to the bumper structure, removing the lights is OK, but taking the plasma cutter to the structure it was mounted to is not.

    Do the 240's and 280's share the same PN for the dash?

    Being overweight sucks. Still gets under my skin that the great re-alignment couldn't have bumped the 240 & the RX7 up 50# to give cars like the 280 a fighting chance to make weight.

  12. #12
    Join Date
    Dec 2001
    Location
    raleigh, nc, usa
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    5,252

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    Has anyone built a to the max 280z? Chris's car is fast, and I didn't realize it was that much overweight.

    We have the same issue with teh 260 as Ron notes, although I think if he redid the cage and spent the jack on 9 lb wheels he could get close to min.
    NC Region
    1980 ITS Triumph TR8

  13. #13
    Join Date
    Feb 2010
    Location
    LYNCHBURG VA
    Posts
    26

    Default 280z

    I think a real to the max buid could be very fast..

    because I do not have much time.. Kids Work house etc. I just race the thing, If could get some weight out and do some development I think it could be a lot faster, heck this thing has KYB shocks on the back ! I have never even checked the cross weight ! The result to effort ratio is pretty good.

    Thanks for some of the ideas, I will keep you guys informed how much some of the things weigh as I get them out.

    Thanks
    Plucker

  14. #14
    Join Date
    Jul 2004
    Location
    Raleigh NC
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    Min weight is hard to get in the later Zs. We recently cross weighted and set mine up and we're going to end up about 56 lbs over with 183 lbs driver and min fuel. Just no two ways around it. Sure, we could ditch the 11 lbs of cool suit but I think that 11 lbs makes me more than 11 lbs of weight faster for sure - can't drive when you're passed out.

    But, then again, maybe it is possible....I have a solid front sway bar, lose some weight there. Redo the entire cage at 1.5". Drop the cool suit. Lose one mirror. Lighten the seat. Remove seat padding. Remove EGTs (they are large ones that weigh around 1 lb each). Remove some scaffolding around the fuel cell. Ditch the fuel pressure gauge. Drop the voltage gauge....but then I'd be building another car and I don't want to build another Z.

  15. #15
    Join Date
    Dec 2001
    Location
    raleigh, nc, usa
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    5,252

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    Cool suit is needed, I agree. The cage is the big issue with your car I think Ron, and like you said that ain't getting corrected. You aren't much over now as is, maybe 30 lbs from a "safe" 20 over (hell CMP and VIR scales read that much difference).

    There is still undercoating on your car. Maybe 5 lbs? Mirror, same. WAY TOO MANY SWITCHES. Camera stuff? Windshield? i bet we can find 30 lbs if we look.

    Chris, you are damn right, you do really well with that car. It's fast.

    See you Saturday.

    Jeff
    NC Region
    1980 ITS Triumph TR8

  16. #16
    Join Date
    Jun 2005
    Location
    New Smyrna Beach, Florida, USA
    Posts
    26

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    Good suggestions above.

    We ran a 280 in ITS in the early to mid 90's and took it about as far as we could on our limited dollars. Seems like we were about 50# lighter than yours. The car could run top 5 to 7 in thirty car fields with a best of third, but never won. As more SPEEDSOURCE RX7's showed up we slippED further back.

    Finally gave up and built a 240.............immediately 2 to 3 seconds faster at Daytona & Sebring, 200 # lighter, better handling, better braking, and better accel off corner.......
    ... more SPEEDSOURCE cars show up ...still 5th to 7th or sometimes 10th.

    GAVE UP......switch car to E Prod....win races!!!

    Mike Van Steenburg & Grayson Upchurch and SPEEDSOURCE EP cars show up........lose races!

    Go back to ITS with 240SX.....some top three's...usually top 5
    BMW's show up, more and newer SPEEDSOURCE cars show up, slip further back

    Give up

    Switch to GTA & SPO with V8 StockCar win races................
    Jay Marshall, Greg Cecil, Bob Stretch, Tony Amico,Charles Wicht, Larry Hoopaugh show up......
    LOSE RACES.

    So what do we do now.........building GT-1/Rolex GT Corvette
    so we can lose to Dave Machavern, Jeff Emery and everybody in GA

    YA GOTTA LOVE IT!

    Bosco
    Last edited by bosco; 03-12-2010 at 11:05 AM.

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