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just one question, although the toe in bump and droop does not change 1/8" in, is the track width changing answer yes, is this a cause of my problem?

'

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this story shall the good man teach his son,
and chrispin chrispian shall ne'er go by,
from this day to the end of the world.
but we in it shall be remembered.

You may also consider taking it to an alignment shop for a second opinion, telling them nothing other than "can you please help align this", and see what they find.

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Midlana book: Build this mid-engine Locost!, http://midlana.com/stuff/book/
Kimini book: Designing mid-engine cars using FWD drivetrains
Both available from https://www.lulu.com/

^This. Or just tell them to give you the report, not to change anything.

Cars with independent suspensions have track change. Unless you've done something unconventional I doubt that's the issue. And that brings us back to 'it was fine before'.

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Peace, Ron

well i re did the front.

first i had to make something that would allow the wheels to move sideways without resistance, that accomplished i wanted repeat data and checked every setting three times and back checked after other adjustments, if i set the camber then the caster, i went back and checked the camber again to verify.
both sides are camber 2 degrees, castor 10 degrees, toe 1/16" tow in and bump steer was 3/16" in at 2" of droop and 1/18" in at 2" of bump.

the steering is improved as is self centering as expected with the castor of 10 degrees.

i examined every ball joint and heim joint for any play or stiffness and found none.

drove the car no change in directional stability just goes where it wants to without warning, i am now confident it is not the front.

when driving the car it will change direction and hold that course until it decides to change direction again unless i input on the wheel, say it twitches to the right, it will hold a straight line in that direction until it twitches again, it may twitch right and hold that line or left and hold that line.

it does not feel like it is turning left or right as once it twitches it holds that course, it does not continue to turn in the direction it twitched, it will hold, how can i describe it, if it twitches 5 degrees off course it will stay straight on that 5 degree course until it twitches again or i correct it to straight.

this leads me to believe that as said before, that something is loose or moving, there is a very small amount of play in the drivers side rear wheel bearing but do not think this is sufficient to cause the twitching, i have checked all the joints at the rear replacing as necessary, they are all good, the rear control arms have no cracks and i have removed the rear sway bar.

it does not appear to change direction with the throttle or under braking.

i wish i could watch the car from the rear when driving but i can't be in two places at once.

i will re check the alignment at the rear, what else can i do.

i will go out in the shop and swap the tires from front to back now.

_________________
this story shall the good man teach his son,
and chrispin chrispian shall ne'er go by,
from this day to the end of the world.
but we in it shall be remembered.

If you have a GoPro or equivalent, you can!

_________________
Midlana book: Build this mid-engine Locost!, http://midlana.com/stuff/book/
Kimini book: Designing mid-engine cars using FWD drivetrains
Both available from https://www.lulu.com/

so i took the back wheels off to swap with the front, also made a very slight adjustment to the rear toe and the camber on the drivers side, change the wheels and lowered the car.

just to verify, i jumped up and down on the rear to settle the suspension and noticed that the right front was lifting up as the left rear was going down but the right rear also seemed like it was not moving at all.

i removed the wheels and looked at the coil overs, counting the threads on the spring perch, they were the same within half a turn, then i turned my attention to the damper adjustment finding the right rear was at maximum and the left rear was at minimum, i adjusted them to position 2 out of 10 the same as the front.

test drive no twitching problem solved, what can i say, i'm not in the habit of bouncing on the rear of my car and apart from the twitching, there were no signs of a ride problem.

what do you think of that?

_________________
this story shall the good man teach his son,
and chrispin chrispian shall ne'er go by,
from this day to the end of the world.
but we in it shall be remembered.

As Carroll Smith has said, “A dead shock is surprisingly difficult for the driver to identify or isolate”.

In your case I suspect two vastly different shocks could fall into a similar ‘category’.

Great you got it fixed and thanks for letting us know.

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Peace, Ron

Love it! Persistence paid off! Good on you and thanks a bunch for sharing the solution

_________________
Perry

'If man built it, man can fix it'
"No one ever told me I couldn't do it."
"If you can't build it safe, don't build it."

Perry's Locost Super Che7enette Build
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Perry's 5th Build the Super Slant 6 Super 7
Perry's Final Build the 1929 Mercedes Gazelle

Well done. Your stick-to-it determination paid off. Now look at all the things you know are in top shape.

_________________
Chuck.

“Any suspension will work if you don’t let it.” - Colin Chapman

Visit my ongoing MGB Rustoration log: over HERE

Or my Wankel powered Locost log : over HERE

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Great, John. Happy the twitchyness is resolved.

But two items were changed: Shock adjustment and the wheel/tire fore-and-aft swap (not to mention the other minor tweaks.) Just to confirm that the shocks were the only culprits, you might consider reversing the wheel swap and testing again.

Or perhaps leave well-enough alone.

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Cheers, Tom

My Car9 build: viewtopic.php?f=35&t=14613
"It's the construction of the car-the sheer lunacy and joy of making diverse parts come together and work as one-that counts."
Ultima Spyder, Northstar 4.0, Porsche G50/52

Agree on changing only one thing at a time. Regarding the shock valving, how did that happen and when?

_________________
Midlana book: Build this mid-engine Locost!, http://midlana.com/stuff/book/
Kimini book: Designing mid-engine cars using FWD drivetrains
Both available from https://www.lulu.com/

don't know how it happened, i guess it was me having one of my "moments"

i have returned the wheels/tires to their original position to see if it comes back.

now i must look at the quick release steering wheel hub as there is a lot of play in it, it's the hexagon type and are known to wear, it is probably a throw away, i will get a new one.

no chance of another test drive yet, i will keep you posted.

_________________
this story shall the good man teach his son,
and chrispin chrispian shall ne'er go by,
from this day to the end of the world.
but we in it shall be remembered.

A thumb screw through the side of the wheel hub can take the slop out of the engagement. Just need to back it off a little to remove the wheel.

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Miata UBJ: ES-2074R('70s maz pickup)
Ford IFS viewtopic.php?f=5&t=13225&p=134742
Simple Spring select viewtopic.php?f=5&t=11815
LxWxHt
360LA 442E: 134.5x46x15
Lotus7:115x39x7.25
Tiger Avon:114x40x13.3-12.6
Champion/Book:114x42x11
Gibbs/Haynes:122x42x14
VoDou:113x44x14
McSorley 442:122x46x14
Collins 241:127x46x12

I once pulled a head off my daily driver because I did a seasonal adjustment (Canadian Prairies, so major adjustment) on a pair of SU's- but... I switched hands and leaned one several flats and richened the other. Because the car had been overheated a couple weeks before, I saw the ghost white plugs on two cyl as a headgasket failure.

Point of the story is, when tired, "duplicating" a re-set from one side to the other- especially if you've had to roll the creeper over, re-situate yourself *and* change hands...is almost inevitably going to end up exactly wrong.

still twitching?
no not twitching but a sense of wandering, almost rithmic in nature.

set the car up with parallel string lines the same distance apart aligning them equally from the center of each wheel to the string line so toe is not a factor, maybe, thus placing the car centrally in a rectangle and took measurements of 1. rear toe and adjusted until i had 1/16" per side and 1/8" o/a.
rear camber was set at 1-1/2 degrees negative.
front camber was set at 2-3/4 degrees negative with the camber gauge on the discs, castor was set at 9-1/2 degrees positive again with the gauge on the discs, toe was set at 1/16" per side and 1/8" o/a.
i checked these measurements 5 times and they repeated even when rocking the car and bouncing on it.
i replaced the steering rack and checked all the hiem joints and ball joints, all was good.

as i am using a basic 442 chassis from Jim McSorley i thought i would ask him why in his front suspension write up the first thing he mentions is that the front track must be equal or wider than the front track but his e-mail goes nowhere any more.
the point is that i am narrower in the front than the back, not by a lot probably 1".
are we comming back to ackerman? having the spindles closer together, from memory, was an attempt to move the convergent point from behind the car closer to the axle.

tomorrow i will set the car up again in the string box exactly as before and log the difference in axle width front to back, then i will remove the front coil overs and check the bump steer again now that i have put about 50 miles on it.

_________________
this story shall the good man teach his son,
and chrispin chrispian shall ne'er go by,
from this day to the end of the world.
but we in it shall be remembered.