bjhines Posted December 5, 2006 Share Posted December 5, 2006 lol... why don't you just put a 2-stroke in it then... IIRC... the rotarys are not light.. they are compact but dense Quote Link to comment Share on other sites More sharing options...
JustinOlson Posted December 5, 2006 Share Posted December 5, 2006 Honestly I don’t agree with swish cheesing the chassis to lose weight. You are really opening yourself up to a lot of spots for crack propagation. Quote Link to comment Share on other sites More sharing options...
johnc Posted December 5, 2006 Share Posted December 5, 2006 You can also take a bunch of weight out of the engine and driveline. 17 lbs can be taken out the L6 crank. AL or Ti rods save about 5 lbs. A double disc clutch and a minimal flywheel saves 35 lbs. AL small OD gun drilled driveshaft saves 8 lbs. AL CV shafts save 6 lbs. Back cutting the ring gear saves 1.5 lbs. That's 72.5 lbs out of stuff that's spinning. 15" x 10" wheels are about 9lbs each. Hoosier bias play race slicks to fit the above wheels are about 12 lbs each. That probably saves 60 lbs over stock wheels and tires. Quote Link to comment Share on other sites More sharing options...
OlderThanMe Posted December 5, 2006 Share Posted December 5, 2006 Or you could build a tube frame and hang a carbon fiber body of a Z on it...not the cheapest way but it is the most effective.Just putting it out there. Plus you have the oportunity to do away with the struts an put whatever suspension you want in the car. I agree with Johnc on the driveline stuff...the L6 crank is a heavy beast!!! Quote Link to comment Share on other sites More sharing options...
frank280zx Posted December 5, 2006 Share Posted December 5, 2006 Got some correspondence recently on someone building a Group 4 240. he decided the FRP kit was not light enough so it's going to be Carbon Fiber. Then he got it in his head that the aluminum bolts that are supposed to hold the fenders on were to heavy, so he hit the heads with a ball mill, then gundrilled the M6 bolts with a 2mm drill....to lighten the fasteners further.Gundrilled the replacement Titanium Rear A-Arm bolts as well... Some people say they "want to reduce weight" and from now on I will always be able to tell if they are serious when I ask "have you ball milled the heads and gundrilled all the Aluminim M6 fasteners on the car yet?" LOL! haha well i think i know who you talking about yup it is true .. all you dont have to accelerate you dont have to brake .. this will be a beast .. a fine prepped full FIA group 4 Quote Link to comment Share on other sites More sharing options...
zguy36 Posted December 5, 2006 Share Posted December 5, 2006 Rotary engines are LIGHT! I don't have an exact number, but I can tell you that a friend and I lifted a long block into the back of his geo without even having to try. Weight savings doesn't do you a lot of good though, when you lose the reliability of your engine! Quote Link to comment Share on other sites More sharing options...
JMortensen Posted December 5, 2006 Share Posted December 5, 2006 Let's keep this on topic... Quote Link to comment Share on other sites More sharing options...
bjhines Posted December 5, 2006 Share Posted December 5, 2006 aluminum brake calipers vs the cast iron anchors from the Landcruisers... Lightweight race rotors with aluminum hats... aluminum hubs, aluminum steering knuckles, tubular tie rods, tubular TC rods, aluminum control arms, lighter coilover springs, aluminum strut top assys, You can grind off quite a bit of material from the spindle forgings(between the caliper mount ears, and all the way around the circumference for the backing plate... Tubular sway bar with aluminum arms and lightweight end links... That is all unsprung weight... most of it can be had from Arizona Z-car... http://www.arizonazcar.com/ ... I would have used a lightweight racing ball joint in the CNC control arms.. and toss out the heavy Datsun ball joint... Also for really anal engineers.. mounting the calipers as low as possible on the spindles(clocked around to 5 or 7 o'clock to keep center of gravity as low as possible... Reinforcing the chassis will add some weight back.. but most of it will be low in the car... Quote Link to comment Share on other sites More sharing options...
bjhines Posted December 5, 2006 Share Posted December 5, 2006 You can replace the entire rear differential and suspension mount assembly with stiffer lighter aluminum pieces... While your at it... stick with the lighter R-180 and hack off all the unused mounting tabs... loose the heavy front mount and chuck the assestor strap hardware in the trash.. Use an alternate style top mount... Ron Tyler mount... loose the spare tire well and the heavy fuel tank.. replace with an aluminum can and sheeting... Quote Link to comment Share on other sites More sharing options...
thehelix112 Posted December 5, 2006 Share Posted December 5, 2006 bj, I am not sure what you mean about mounting the calipers `low on the spindles'. Are you just talking about the 5/7 o'clock mounting position? Some random thoughts: while you are correct in that this lowers the centre of gravity of the strut assembly, as this is sprung, it does not affect the centre of gravity of the car at all; and thus its only affect is in determining the magnitude of the moment placed on the chassis by the strut assembly when in a turn. This moment on the inside wheel will attempt to pitch the car undesirably (out of the corner), but on the outside wheel it will attempt to pitch the car into the corner. I would hazard a guess that these two moments would all-but cancel each other out, and you're left with no impact at all. Unless I have missed something incredibly obvious. This is something I have never completely understood, and am keen to do so. Though it might be better in another thread? Dave Quote Link to comment Share on other sites More sharing options...
QuickSilverAWD Posted December 6, 2006 Share Posted December 6, 2006 Best way to drop weight... SWAP TO A ROTARY ENGINE. rotary is light. that would drop alot of weight You would drop even more weight when you have to remove the damn engine every 30k miles or 5 track runs to replace the apex seals. Quote Link to comment Share on other sites More sharing options...
LS1 240Z Posted December 6, 2006 Share Posted December 6, 2006 removing interior, putting rollcage in it, removing door supports, fiberglass or no bumpers and then a fiberglass or carbon hood, lexan windows. anything more than that and IMO you could be spending your time better elsewhere also a good way to lighten up the car is to put an LS1 and a solid axle in it Quote Link to comment Share on other sites More sharing options...
OlderThanMe Posted December 9, 2006 Share Posted December 9, 2006 anything more than that and IMO you could be spending your time better elsewhere yeah...like getting on a good diet... Quote Link to comment Share on other sites More sharing options...
boodlefoof Posted December 9, 2006 Share Posted December 9, 2006 Or you could build a tube frame and hang a carbon fiber body of a Z on it...not the cheapest way but it is the most effective.Just putting it out there.Plus you have the oportunity to do away with the struts an put whatever suspension you want in the car. I agree with Johnc on the driveline stuff...the L6 crank is a heavy beast!!! Yup, that's one way to do it! Although when the spaceframe is done I think it is going to be around 325 pounds. Quote Link to comment Share on other sites More sharing options...
johnc Posted December 9, 2006 Share Posted December 9, 2006 Kenny Bernstien, back when he was either trying to break the 300mph mark or get into the 4s, figured it cost $1,000 to remove a pound from his top fuel dragster. He went on a diet, lost 17 pounds, and later that year hit his target number. Kenny calle dit, "The best $17,000 I ever saved." Quote Link to comment Share on other sites More sharing options...
Guest Mike Posted December 9, 2006 Share Posted December 9, 2006 Hah... that's funny!! Quote Link to comment Share on other sites More sharing options...
fhptom Posted January 21, 2007 Share Posted January 21, 2007 For what it is worth I just removed my dash in my 260 (reading somewhere in here I would lose 50-60lbs) was actually 25lbs. Stock seats were 30 lbs each. My Hoosier DOT bias tires 16x8.5 weigh 21 lbs each. Hoosier web site puts new slicks at 20 lbs each. Quote Link to comment Share on other sites More sharing options...
jonus079 Posted January 21, 2007 Share Posted January 21, 2007 best $17,000 I ever saved lol good one Quote Link to comment Share on other sites More sharing options...
cyrus Posted January 22, 2007 Share Posted January 22, 2007 Back in the realistic road range small battery -30 lbs no spare jack etc. (AAA instead) -50 lbs no radio -10 lbs light wheels/tires -60 lbs No donuts -(insert your fat here) lbs These are the best easy mods. Quote Link to comment Share on other sites More sharing options...
Guest GSRacing Posted June 27, 2007 Share Posted June 27, 2007 aluminum brake calipers vs the cast iron anchors from the Landcruisers... Lightweight race rotors with aluminum hats... aluminum hubs, aluminum steering knuckles, tubular tie rods, tubular TC rods, aluminum control arms, lighter coilover springs, aluminum strut top assys, You can grind off quite a bit of material from the spindle forgings(between the caliper mount ears, and all the way around the circumference for the backing plate... Tubular sway bar with aluminum arms and lightweight end links... That is all unsprung weight... most of it can be had from Arizona Z-car... http://www.arizonazcar.com/ ... I would have used a lightweight racing ball joint in the CNC control arms.. and toss out the heavy Datsun ball joint... Also for really anal engineers.. mounting the calipers as low as possible on the spindles(clocked around to 5 or 7 o'clock to keep center of gravity as low as possible... Reinforcing the chassis will add some weight back.. but most of it will be low in the car... Quote is ref to pictures above, with that sort of tubular front end, welding the inner gaurd to it (the tube) becomes redundant. You would be better off replacing all sheetwork (forward of firewall) with FRP or Carbon fibre panels (regulations pending obviously). BTW: Good to see there is a forum with people that are well infomed and educated, being a young engineer I am sick of (In australia we have "Commodore and Falcons" GM and Ford repectively, )where by the majority of owners are the 17-25year old range and have little to no mechanical knowledge. This is a refreshing forum, that i feel i may actually join nin on a regular basis without the need to bash my head against the wall (talk to ill-informed youths) Cheers, and top forum hey! Quote Link to comment Share on other sites More sharing options...
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