negative camber/avoid that wall/tree/dog

[126dave]

hi all,i want to put some negative camber on my front end,im hoping to ''plant it'' a little better when under power thro the bends,im just kicking some ideas around at the mo,i'v heared of redrilling the kingpins and welding offset washers on,but,is there any easier way?.............i was thinking of machining some material from the ends of the top wishbone/removing some shims? :shock: ...what does anyone think of that idea?..........or does anyone have some modded kingpins/wishbones laying around??? .

id like to tie this project in for when my brakes finally arrive :roll:

[126dave]

well i think im going to go down the road of modding and welding the wish bones........i have some spare BIS ones to play with.im going to add some radical neg like my mates sunbeam stilleto had in the 70's.....

[hudsonhenry]

Dave

Are you going to do the backs as well? I am looking for the best way to put some neg camber on the back without lowering the car anymore as I have ground clearance issues until I get around to modifying the sump

[126dave]

hi Nigel,well,my rear end has a goodly amount of neg at the moment,its well planted,i will post some pics on ''slag my car'' lol.(does 126 suspension react different to 500 with 30mm lowering kit?,wouldnt think so...both the same?)........im just looking to give some attitude/handling to the front now.........by the way,are BIS upper wishbones the same as aircooled?......hope so.........by the way,are you thinking of dry sump mods to the 500.........shame im not based in the UK,id love to meet up an ''chew the fat'' with you

as a PS,car going really well for a 650 twin,more than happy with mods so far. :cool:

[hudsonhenry]

Dave

I have standard saggy springs at the back with AVO dampers, I didn't want to buy new springs untill I knew what effect the heavier engine would have on the ride height, it looks fairly reasonable at the moment. I probably need to work out the ideal spring rate and ride height and get some made up.

No plans to dry sump but was thinking about making the sump shallower but with added wings, baffles and trap doors, a bit cheaper that way.

I'm not sure about the BIS upper wishbones, I was toying with the idea of a fully rose jointed twin wishbone set-up with coilovers, Nanni do one but its quite pricey, I thought that kit car wishbones of some kind might do the job, still I'm supposed to be having a break from chopping bits up, I promised the my wife and daughters that I would give them some of my time for a while!

I would love to get together, if you ever get over this way let me know.

The tuned aircooled is good fun, ideal for where you are, no motorways to sit on for hours at high revs, and they make a great noise. :twisted:

[126dave]

yeh,i been wondering about the rear spring set up for your car,thats a hard thing to get right as per my other posts,good luck!,but your better placed than me for that!.i have some 650 springs here for free with 21,000 miles on them if you want to play with them?
your sump ideas sound good,and maybe add oil cooler from a 2cv or something to up capacity?

that double wishbone set up is great,but a bit £much£ for road use methinks.

i've already made up a slave  BIS wishbone,giving 10mm at the wishbone neg camber,and have ordered a set of new 650 ones from gerstl (24ish euro each with bushes etc).............will keep all you tuners out there posted on progress

your correct,jersey is ideal for a tuned 650!.just need to sort my cornering out now!!....thats the secret as you know,keeping the loud pedal planted!!!..........does give mpg probs......tank full less than 80 miles :cool:

and.......our friend has sent another set of discs etc to me this week i think

[Bruce]

can't think offhand how to do the back without lowering but the front is easier, there should be some spacers under the uper wishbones to give the wheels positive camber, taking these out will give you nagative. one thing to watch out for though is this will wreck your tyres; my de-ville had a bit of negative camber when i first got it and the tryes wore out at an alarming rate, they only lasted a few thousend miles. No amount of tracking adjustement would cure the problem and the only way i could fix it was to put more spacers under the uper wishbones.

The problem is you do not want the negative camber on the wheels when going straight, what you need to aim for is to have increased negative camber on the outside wheel and increased positive on the outside wheel when turning. this is taken car of by the suspesion geometry to a certain degree, increasing the caster angle of the front suspension can increase the negative camber on the outside wheel but it also increases the positive camber on the inside wheel.

What you need to do is move the bottom mount forward and/or the top mount back, moving the bottom mount will involve moving the spring which i don't think is practicle, but moving the top is a lot easier; to move the top back you must do exactly the same on each side. take the spacer from the back of the uper wishbone and put it on the front.

Do it a little at a time and test drive the car after each change, it will have the effect of making the steering heavier of lighter at higher or lower speeds, change it to much and the slow steering will be too heavy, and high speed will become dangerously skittish.

[126dave]

neg or poss camber should not increase tyre wear,excessive toe in or out will,your de ville must have had some problms with crash damage/knacked spring? to have had neg camber at the front???126's have pos front and rear when lightly loaded going to neg rear under load,tyre wear for the standerd car is average i think?.(like triumph herald /vitess/VW/spitfire?)

i wouldnt play with the shims on the top link at all,they compensate for body shell differences etc,if i had suspension /tyre wear probs id look else where before tampering with that area.
so my 10mm will still be correct as per the body shell,and the base trim from the factory will remain.i wont play with castor angle,way beyond my ability.

all my other suspension bits are new,im just adding neg with the front end realigned yet again.

[Bruce]

yes mine had suffered some crash damaged, the tracking was spot on, and i cured the problem by putting some extra shims under the wishbones.

[slater]

neg or poss camber should not increase tyre wear

It most cirtanly will. You end up with one edge of the tyre wearing more than the other and it wears alot quicker than normal as theres more pressure on a smaller surface area.

The more camber the worse it will be but you can help it by swapping the tyres around if they are symetrical ones

[126dave]

im used to high tyre wear on things,i run a 'blade and an SP1,SP1 can eat a rear (130ish quid) in 2-3 k miles :twisted: .......so a bit extra wear on the (relativly) cheap 126 tyres doesnt fase me at all....i still stand by the fact its tracking that causes most wear.

if we could keep this thread to the whys and wear (sic) fores of acheiving neg cam that would be great.

[Bruce]

i wouldn't call the tyres on my 126 cheap, the 165/55/13s i have cost more than the 205/70/14s i used to have on my 280SE, granted they are not the same price as tyres for big bikes, but when you need 4 the price is actually more.

[126dave]

top track arms are on order from gerstl(yet another back order tho)..when they come im going to drill and weld then as per my jig,i'll let you know in due course if my tyres wear radicaly,but to be honest,if i can cure the bump steer thro the fast corners i really do not care about the tyres.................but,i gota say this,as for neg or pos camber affecting wear,i really dont see it,my bis has both,and tyres wear evenly,even driven hard like it is.........time will tell tho on the more radical neg im aiming for.......... :cool:

[hudsonhenry]

Now thats what I call negative camber :shock:

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[126dave]

:shock: well bruce,id def agree there would be some inner edge tyre issues there!!!!!!!!!!!!..........