Dash fuckwittery, etc.

[Roy Kemp]

Hi all,

Actually managed to wangle a few spare hours to work on the Dutton yesterday. Which, given present commitments, is a minor miracle in itself. So, you may recall from previous blog posts that I've got a pile of fancy bits to fit, stuff to fix, things to modify/improve, etc.

So, I decided to have a decent loo at my front suspension which has always been a bit of a bugbear of mine. The car is phenomenally understeery, even taking the locking diff into account. I've got adjustable bottom arms which need bottom shock mounts welding on before I can fit, however, looking at the front struts it appears I've got the cheapo motorcycle shocks. I've always suspected my car is way too high at the front, and it needs to come down a fail old bit. Anyone know if you can change the springs on these crappy old struts? If not, it doesn't make sense to fab up brackets for the new arms to suit these if I'm going to have to go down the coilover route. So, this job was successfully f**ked off for now.

Next, I pulled off the dash and steering wheel for a look at what's under there for fitting the Corsa PAS column. Oh, wait, sorry, I skipped a stage. I was trimming all the old Corsa switchgear off and managed to completely butcher the top bearing in the process. So, that's that fooked. I guess this column will only get to serve as a dummy for test fitting! Anyway, removing the dash revealed not-as-bad-as-feared wiring, but a complete abortion of an arrangement holding the steering column into the car. As per the photo, there's a bit of angle iron bolted loosely through the tub running vertically. Then, loosely "bolted" to this, a horizontal piece hung from a broken part of the tub, from which the column hangs. Horrendous. Needless to say, this is all coming out.

Current plan is to run a bit of tube across the car behind the dash. This will pick up two backing plates to sit behind where the screen bolts onto. This should hopefully cure the tub flexing that's cracking my windscreens. This will be bracketed down to the chassis. Hopefully I can position this so it's not a total nightmare to hang the rear steering column mounts from. Will see if I can retain the collapsibility of the column with this arrangement. Not had a look at the front column mounts yet but suffice to say they look fairly poxy. Might need another cross-tube.

Bloody thing will weight a tonne by the time I'm finished.

[Roy Kemp]

And in response to a post below, my ARB is 19mm which I don't think is one of the RS or fancy ones.

[Roy Kemp]

Hi again guys - all very interesting discussion, but I fear we're getting a little off-topic here. I've found a photo of the exact setup that I'm hoping to achieve. Can someone tell me why this is such a bad thing?

[Dave Adams]

HOW TO DETERMINE ACTIVE COILS OF A COIL SPRING

Count total number of coils, subtract a coil for each coil that touches, these are dead coils. Ground flat ends are a dead coil. Start count with cut-off end facing you directly above would be one and so on. Not all coil springs are even coiled. You can have 1/4, 3/8, 1/2, 5/8, 3/4 or 1/8 of a coil (Example 10 1/8 coils).

1. If you cut one coil from a spring, the rate will increase.
2. Increasing wire diameter, will cause a great increase in rate.
3. Nothing in spring rate calculation indicates that a coil spring ever changes rate. The rate is determined by material and dimension of the spring. Coil springs don't wear out or lose their rate.
4. Spring load determines how much load a spring can support at a given height. The rate only tells how much height will change as load is changed. A spring can lose its load height over time if steel is not heat treated properly. When a spring sags, its rate is still the same as when it was new.

[Dave Adams]

those TCA's are also for compression struts as well......so the anti roll bar can be binned.

[Dave Adams]

the point i was trying to show Vern was that adjustable TCA's with shocker mounts exist. and it is perfectly acceptable for an individual with modest skills to make their own for their own cars.

whether that is a good idea or not is another question.

[Dave Adams]

the point Paul Thomas isnt that the castor angles will alter.......

its that the dutton chassis seems to have so poorly jigged that the geometry on the car is out. its not unusual to have different castor either side of the car. my last S1 had 0.5 Degrees castor on the O/S and 5 degrees on the N/S. by moving the anti roll bar mounts you could correct some abysmal construction errors by the factory.

besides any car as light as ours can live with anything between 1 and 8 degrees of castor. the thing is that after i moved my anti roll bar mounts on the Legerra it evened up the castor both sides.

[Dave Adams]

Look at the bottom of the page.
Point 1 states reducing the number of coils will increase spring rate......I am 53 and remember that from o level physics at school...

[Dave Adams]

See here.....an article on how to work it out...
http://www.bluecoilspring.com/rate.htm

[Dave Adams]

Wrong rob...
A coil spring rate is determined by wire diameter and number of coils (plus some other factors) it's basic physics that a coil spring of 10 cois cut by 1 coil will"gain" about 10% spring rate thus a 100lb / in spring will be a 110lb/in spring.

[rob saul]

Cutting springs down doesn't alter spring rate !!!
Your not altering the diameter or spec of the steel
A 12" 200lb spring cut in half just results in 2 6" 200lb spring