bjhines Posted June 26, 2006 Author Share Posted June 26, 2006 IIRC This panel does not even exist in the very first 240Z cars.... I think it adds stiffness... but it is overweight.... You can tell that this storage area was an afterthought... it has none of the attributes of the other sections of the original unibody design.... I have punched it full of holes... but i cannot use my flanging die on most of them.... Quote Link to comment Share on other sites More sharing options...
EZ-E Posted June 26, 2006 Share Posted June 26, 2006 I weighed my current track prepped 1972 240Z with stock drivetrain... that sucker has a lot of things stripped off of it.... and it weighs 2499 pounds with me in it and 8 gallons of fuel.... A fella in my club is running a very highly prepared 280Z chassis... with fuel injection.... he has gone through the entire chassis and removed every little bracket' date=' nut, bolt, CF hood, etc... his car only weighed 2200 pounds with him in it and 4 gallons of fuel.... we both weigh about 170 pounds.... I am taking this car even further... I have a HUGE PILE of parts that I will weigh when I am done.... ANYONE who knows what they are doing in this respect will agree completely with my approach... lightness makes speed... EVERY ounce COUNTS.... race car builders get a hard on when they can remove another handful of metal... It is all part of the COMPLETE project... I have ABSOLUTLELY NO concerns about chassis flex.... the damn car is getting a full cage... I have another thread about the "tt cage" and chassis reinforcement.... the lightening goes hand in hand with the fact I am adding a whole lot of weight with the cage and reinforcement.[/quote'] My 71 completely stock less the ac becuase it was locked up and might have saved me 80-100 lbs weighed in at 2250 with about 3/4 a tank of gas. I was'nt in the car though. This is just total car weight. That though is with spare tire and all of the interior. What more was in your car to add the weight on the 72? I would figure I could lighten that Z to about 2k lbs easily, and with me in it would make it back to stock weight at around 2200. I guess those cages and such wiegh in a big amount hmm. Quote Link to comment Share on other sites More sharing options...
bjhines Posted June 26, 2006 Author Share Posted June 26, 2006 yea.. the cage can add over a hundred pounds.... but I swear I dont know what is keeping my current track car so heavy.... It seemed odd to me as well.... I have removed the bumpers and lightened the battery... most of the interior is still in place... no spare tire... of course... I weigh 170 pounds... so we are not far off... espcially considering mine has a cage... Quote Link to comment Share on other sites More sharing options...
DemonZ Posted June 26, 2006 Share Posted June 26, 2006 if Nissan had not put flares on the holes the panel would be very weak and useless. Since they put flares on the metal it became very strong. when you make a hole and put a flare on it then it gains lots of strength. If you don't flare it then the metal will be much worse off. Without the flare, it's weaker. The flare effectively thickens the sheer panel around that location, and keeps it from distorting as easily. Without the flare, its weaker. The way I see it, it's not the hole that makes it stronger, it's the flare. Quote Link to comment Share on other sites More sharing options...
Pop N Wood Posted June 26, 2006 Share Posted June 26, 2006 ANYONE who knows what they are doing in this respect will agree completely with my approach... . Man. Quote Link to comment Share on other sites More sharing options...
bjhines Posted June 26, 2006 Author Share Posted June 26, 2006 tough crowd... hey I just type this stuff out without a lot of political correctness editing... I am looking for suggestions... and feedback... I just get a little frustrated with some of the Why's... There is another thread about this same project active... I have posted dozens of pictures... It is just nuts for someone to pop in and say..."what a waste of time"... why would you do that?... provide ideas.. not naive critical blurts. This kind of thing has been done since men put things in motion... there is a great deal of hard science to back this up... punching, flanging, beading... it all matters to someone who want's to do everything possible to make their car fast on an actual race track... This is to be a no holds barred supercar... in all respects... 18 posts could be cut out of this thread because they go back and forth over the validity of lightening the chassis... rediculous... Please don't get too sensitive about my PC... I have a lot of friends in a lot of clubs... We can all deal with each other face to face without a great deal of PC editing in our communications.. Quote Link to comment Share on other sites More sharing options...
OlderThanMe Posted June 26, 2006 Share Posted June 26, 2006 yes. the less metal you have (the holes) and more even smooth curves(strength) you have the lightest, fastest, most stiff car you will have. a little yota-ism... you need the metal to keep stiffness but a lot of it is wasted in just being a flat sheet. I like a project to make the ligtest, fastest car and it should not be down-talked. Quote Link to comment Share on other sites More sharing options...
Clifton Posted June 26, 2006 Share Posted June 26, 2006 I like it, especially the flair . I did everything I could to take weight off my 71 and did an ok job on the 73 considering it's a street car with a/c. This makes me want to get a hole saw out on both cars. Quote Link to comment Share on other sites More sharing options...
jt1 Posted June 26, 2006 Share Posted June 26, 2006 John, you're doing fine. To show what weight reduction can do, let's consider my car and the aforementioned 2200# 280Z. My car is essentially a street legal V8 240Z, although the mufflers are a little loud. Full interior, lights, glass, heater, stereo, blah blah. Put a tag on it and drive it around. It weighs right at 2700# on track with driver, and it's about 480hp at the crank, probably about double the 280Z. We were both doing a time trial at VIR a while back. No contest, right? 480 hp versus a lightly modded L6, with both cars running the same size Hoosiers, it's the V8 all the way, no problem, right? He has more experience at VIR, and gets around a little better than me, but I'm decent, and my car sounds like a winston cup car. I beat the 280Z. By four tenths of a second on a two mile track, not nearly the difference you would expect. So lightening up helps a lot, not only in acceleration, but braking, turning, and transitions. I think I'll go drill some holes in mine right now. jt Quote Link to comment Share on other sites More sharing options...
Guest ON3GO Posted June 26, 2006 Share Posted June 26, 2006 i asked in the other thread but ill try it here. where did ya get the flare tool? i think what your doing is GREAT and i had planned to do the same. thanks! mike Quote Link to comment Share on other sites More sharing options...
JMortensen Posted June 26, 2006 Share Posted June 26, 2006 IIRC This panel does not even exist in the very first 240Z cars.... I think it adds stiffness... but it is overweight.... You can tell that this storage area was an afterthought... it has none of the attributes of the other sections of the original unibody design...I have punched it full of holes... but i cannot use my flanging die on most of them.... What changed is that the early cars didn't have the storage compartments, they had tool covers on the uprights behind the seats. They had a top section with a bunch of flanged holes in it (imagine that), and the vertical face had the rectangular sections cut out. I think the triangular box structure created by the deck and the vertical face is extremely important to the stiffness of the unibody. But, if you're doing a full cage then maybe the stiffness of the unibody isn't so important anymore. My goal in my own project is to strengthen the unibody and the subframes, and to add the stiffness of the roll cage so I stitch welded all this stuff on my car (see pic below). What I don't get is where all the extra weight comes from on the mid 71 and later 240Z cars. I know the console changed and they added the storage compartments, but as you can see in the weights thread my car weighed about the same as John's, when mine had a bunch of extra insulation, full carpet kit, R200, Recaros, L28, 5 speed and an Autopower roll bar and it sounded like his was already mostly stripped down. Weight matters a lot, but I do have to wonder just how much weight you're cutting by taking holes out of the sheetmetal. I guess if you've done everything else and there's nothing more to do and the cage structure is sufficient then it's not going to hurt. I guess like you said you could weigh all the metal you've cut and see what a difference you've made if you really wanted to quantify it. Quote Link to comment Share on other sites More sharing options...
OlderThanMe Posted June 26, 2006 Share Posted June 26, 2006 greenlee Quote Link to comment Share on other sites More sharing options...
bjhines Posted June 27, 2006 Author Share Posted June 27, 2006 Mitler bros machine tools carry a whole line of punches.... I'll try to dig up the catalog.... someone here turned me onto them.... MikeKelly??? Quote Link to comment Share on other sites More sharing options...
bjhines Posted June 27, 2006 Author Share Posted June 27, 2006 In the HP vs weight argument.... My take on it is that... It is hard to use a lot of horsepower to it's fullest degree.... I drive a 240Z that only puts 160 HP to the rear wheels in track alignment... I can embarass factory supercars with my current lightweight/ low HP 240Z... especially at tracks in the South East.... I have wonderful video of my car chasing down 911s, 350Zs, Cx Corvetts, Mustangs, Camaros, BMWs... many of them highly prepped and on race slicks.... They leave me like I'm standing still on the straights... they get 100s of yards away.... and them im back in their tailpipe by turn 3 or 4.... on 17 turn tracks... they get passing flags at every station until they submit... I have a lot of fun with them now.... and I just don't see a lot of horsepower making a huge difference in my times... certainly not what most of you would expect.... That is why I am being so careful to make sure this is a COMPLETE transformatoin.... stiffer, stronger, lighter, balanced, and adjustable.... Quote Link to comment Share on other sites More sharing options...
Thumper Posted June 27, 2006 Share Posted June 27, 2006 Here is the website. http://www.mittlerbros.com/ Its under sheet metal tools. I wonder if you could just use a socket. My sockets are round on the end so I could just find a perfect size and get out my good old hammer. Quote Link to comment Share on other sites More sharing options...
bjhines Posted June 27, 2006 Author Share Posted June 27, 2006 well.... there is a flat area on the outer circumference of the die.... it is there to flatten out the sheet stock with every hole... I have used lots of different things to do this for aluminum aircraft parts... the sheets always come out warped.... the Mittler Bros dies flatten the sheet back out with every hole... for $40 each I suggest you get the 1" greenlee punch and a 1" flaring die... it is a very useful size... there are different bead profiles as well.... I use a round flare.... Quote Link to comment Share on other sites More sharing options...
ZZZero Posted June 27, 2006 Share Posted June 27, 2006 From what I understand The flared holes might actually make the car more rigid,from side to side but not back and forth,if that makes sense, I picture it sort of like an arched bridge they can hold ridiculous amounts of weight,becuzase of their design,? would it be wrong to think of it that way? Quote Link to comment Share on other sites More sharing options...
bjhines Posted June 27, 2006 Author Share Posted June 27, 2006 there are a lot of finer points I do not fully understand about this.... various patterns and hole sizes are used on aircraft parts... this depends entirely on the shape and size of the panel and adjoining parts... If someone finds a good website for this please link to it.... Quote Link to comment Share on other sites More sharing options...
Thumper Posted June 27, 2006 Share Posted June 27, 2006 What about comparing beading to flareing. Would I be right in assuming beading would be stronger than flareing? The same company for the same price offers flaring or beading. Quote Link to comment Share on other sites More sharing options...
Darrel Posted June 27, 2006 Share Posted June 27, 2006 Wow.. that is a reach.... considering it is getting a V-8 installed in this process I would say this car will have "nuts"... The nut I was referring to is the one that goes behind the wheel. Quote Link to comment Share on other sites More sharing options...
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