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    #31
    Yep, that's the one.

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      #32
      Isn't that the body Steiner started with for his first "F5000" ?
      "Where can we get hold of a Vincent Black Shadow?" "Whats that?" "A fantastic bike," I said. "The new model is something like two thousand cubic inches, developing two hundred brake-horsepower at four thousand revolutions per minute on a magnesium frame with two styrofoam seats and a total curb weight of exactly two hundred pounds."

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        #33
        Originally posted by Gammaboy View Post
        Isn't that the body Steiner started with for his first "F5000" ?
        I think he had an original mold to take it from. amazing job that was.

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          #34
          Spent the morning playing around and compromising and think I finally have it. Fully triangulated, 300mm between sprocket centres, room for drive shafts, engine as stressed member (partly-maybe just adding that extra bit ) BUT reduced length of diffuser quite a lot
          Obviously the finished product will have substantially more tape, may even use higher quality 200mph racers tape.
          Really wish I could get my head around uploading these photos. For some reason kept loading upside down or half rotated.
          Attached Files

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            #35
            Sometimes (oftentimes) i can be quite dim. Just looking at those photos after posting and running back out to the garage, realised can still have my original length diffusers and go narrower so have equal width top and bottom attachment points with only oil filling point now an issue- can work around that. Oh happy days.

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              #36
              Well bugga that rear sub-frame took a thousand different iterations to get it right. Don't know how many times had to cut out tubes and start again. It aint pretty up close but it is strong with as much triangulation as I could get in. Had to build in 2 pieces as engine is too wide to lift in and out. Once finished placement of all tubes, welded together permanently. Just need to work out how to finish off the ROP brace as not sure on regulations for that (does anyone know?)and fit a 6mm aluminium plate to brace between engine and diff. Also left tubes on the end as not sure which way I want to attach rear suspension.
              Now jigging up rear uprights ready to weld. Also bought a new Chinese invertor MIG off evilbay. Really impressed with this beast- 260amp, digital display; lite as. Very easy to use and a super stable arc makes it so easy to get a nice weld compared to both other MIGs I've used (Transmig 180 and a cheap 120amp Bunnings pos), even on a 20 metre extension chord. Eats 4mm steel for breakfast and only cost $329.
              Anyway, now feel like I'm getting somewhere. Going to run 2nd hand Formula 3 tyres front and rear. Front suspension will be Formula Vee so stuck with the suspension geometry it came with. The rear suspension geometry is another matter. Need to decide how much travel to accommodate, then work out static/dynamic cambers to build into it. Got no idea where to start there. Suspension geometry, no matter how many times I've read up on it, is witchcraft to me.
              Attached Files

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                #37
                Ah! Now you are really powering on, fabulous stuff.

                Suspension layout? I can only tell you what I know, bugger all. Long arms, the longer the arms the less things change. Bottom arm close to horizontal, top arm, inboard lower. Roll centre between the ground and the centre of gravity, lower the better? I think we tend to give ourselves to much suspension travel, I used to figure on 3 inches of bump and 3 inches of droop now I only look at 2 inches either way... I reckon I read somewhere that the rear roll centre should be 2/3 of the centre of gravity height and front only 1/3... Know your tyre size first, otherwise you are going to have to redo it all.

                At the front end, understand and correct your ackerman to suit your wheelbase.

                I don't know shit, but I haven't yet built a car that was just an absolute pig either.
                " Racing cars don't have doors. Toilets have doors" : Keke Rosberg

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                  #38
                  vsusp.com

                  free to use.
                  ........................................

                  Suzuki Mighty Boy / BEC Rear Mid mount Suzuki 1150cc 450kg Hillclimber [in the build]

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                    #39
                    Thx Dave, know vsusp, great site! It's just what results SHOULD i be designing for that has me stumped. Apparently radials need some static camber with slight progression ( how much??) as they are more compliant than cross ply, which are more forgiving but require almost no progression. May ask the F3 boys and see what they do. Had spoken to Malcolm Oastler (F1 designer) at a hill climb and he was almost dismissive of geometry.
                    Roy, how do you measure CoG, or is it just a guestimation? Thx for tip on suspension travel, will give it 2" either way. What rake are you running? I've read some different thoughts on formula ford forums, they all talk about (eg) 50mm front and 75mm rear ride height, but where are these points measured from- axle centre lines or extreme front and rear of car?
                    Anyway, need to concentrate on mounting Vee front end next, then can play with rear suspension.

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                      #40
                      Originally posted by rodoe View Post
                      Had spoken to Malcolm Oastler (F1 designer) at a hill climb and he was almost dismissive of geometry. .
                      When there's almost Zero movement and the tyre is doing most of the suspension work, geometry doesn't matter worth a damn - the front end of F1s have been a good example of this for years.
                      "Where can we get hold of a Vincent Black Shadow?" "Whats that?" "A fantastic bike," I said. "The new model is something like two thousand cubic inches, developing two hundred brake-horsepower at four thousand revolutions per minute on a magnesium frame with two styrofoam seats and a total curb weight of exactly two hundred pounds."

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                        #41
                        Originally posted by Gammaboy View Post
                        When there's almost Zero movement and the tyre is doing most of the suspension work, geometry doesn't matter worth a damn - the front end of F1s have been a good example of this for years.
                        Probably right Gammaboy.
                        Just trying to mount up the vee front end now. Not looking good at all. Need to cut out 2 tubes out of chassis (not such an issue), and then change the whole mounting of current pedal set up from top pivoting to mounted on floor so can fit steering shaft. Either that or fit a rack- of which i have a choice of 2- in place of the vee steering box.
                        Last choice, find out if selling the Vee front end will pay for rod ends, inserts, tubes, calipers, discs etc to fit A-arms front end. Anyone know what a ready modded link pin, disc brake converted, height adjustable and spring modified Vee front end goes for?

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                          #42
                          Again I only have my own experience to draw from. I run 75 mm from bottom of chassis to ground front and rear. Rake is for aero, I've decided aero means nothing at Collingrove.

                          I'm guessing camber depends on the tyre, I run less than 1 degree, at full bump it would have a little more....at full droop a little less. Long arms = little change. And I still don't see the whole face of the front tyre being used...

                          I suspect that Malcolm is right, the geometry only needs to be there or there abouts. Really it all comes down to outright grip (tyre size and compound) and power to weight on the part of the car. Remember that the serious cars work on putting all of the front weight on the outside tyre in turns with a single shocker front end working the front tyre as hard as possible getting heat into it and extracting maximum adhesion. Given the low tyre pressure and soft compound the actual geometry is probably a secondary consideration (especially considering the other tyre is flailing away in the air).

                          Yes, F1 has totally gone away from the norms in regard to front end geometry, everything is about aero
                          " Racing cars don't have doors. Toilets have doors" : Keke Rosberg

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                            #43
                            I so like your work. Subscribed. Will be awesome gadget.

                            For those people like me who don't have much in the way of your skills there is a simple, fast and cheap way to build a clubman - not an open wheeler like yours but a fast simple gadget.

                            Take a front subframe, rack and Alum A Arms from an FD RX-7 caliper to caliper. Four bolts hold it to a chassis. Then at rear of said home built chassis bolt the rear subframe caliper to caliper Incl the strong diff and Alum A Arms.

                            There's a street registered one that races in Sportscars at Lakeside and it beats everything. Radicals, Minettis you name it. Ugly body but simple and cheap to build and effective and he drives it home. Does .54's. Incredible.

                            The FD Subframes are readily avail and cheap. James Pearson on FB has 'em.
                            Originally posted by Walt Kowalski:
                            I knew it. That orange bastard is controlling the weather with HAARP just to save his Mar-a-Lago property where he intends to host his handler, Vladimir Putin, at next years G7 which will be morphed back into the G8.

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                              #44
                              Thx Roy. What tyres were you using on the little green beast?
                              My cheapest option are 2nd hand set of F3 Hankooks With fronts at 180mm wide and rears at 240mm wide for $200 complete set.
                              Will have aero as mostly being usedcas track day car. Diffuser is 5 , so hopefully 7 inclusive of rake.
                              Walt, i seriously have very little in the way of skills. I'm full of book knowledge but little in the way of hands on skills. Just determined to own a rafe car. Would much prefer to slap the money down on a complete car, just don't have the money. Might look up that beast you're talking about. Sounds simple.

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                                #45
                                Btw, who is the owner or what is that car called?

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