Cortina GT - setting the shocks - advice needed

Leo Landman · 23 Jun 2008, 10:56 (Ref:2235547)

A fellow competitor told us that in some corners our '65 Cortina GT lifted its inside rear wheel several inches off the tarmac. That's not what a Cortina is supposed to do, is it? So we think it's time to sort out the shock absorber settings.

I can't find a brand name, but there's a rotating knob on the side of each shock absorber, that can be adjusted in 24 small steps (clicks). The fronts were set at 12 clicks (= half the maximum stiffness), the rear shocks quite a bit stiffer at 17 (= two thirds).
I have no data on spring rates. All I can add is that there's a single leaf spring at the rear, a 7/8" anti-roll bar and uprated coil springs at the front, and the car turns in well enough.

Next Saturday we have some track time at Zandvoort, and we'd like to try several shock absorber settings. But how do we go about it? Start with the front shocks at maximum and the rears at minimum, and then work our way to the middle? Or adjust only front or rear shocks at a time? Or start with all shocks settings in the middle and work towards the extremes? And how many clicks of change at a time?

There must be a best way to go about this, and I hope some of you will be able to give us some advice. It would be much appreciated.

esper · 23 Jun 2008, 12:10 (Ref:2235599)

leo its vital to know how heavy you are and how do you sit in the car?

morninggents · 23 Jun 2008, 12:17 (Ref:2235614)

Quote:

There must be a best way to go about this, and I hope some of you will be able to give us some advice. It would be much appreciated.

Sopunds like your car is too stiff at the back. Cortinas should be a lot stiffer at the front than back. What rating are your front springs?

Whatever you do at testing never change more than one thing at a time or you can not tell what change works and what does not. If you do not have time to find out your current spring ratings try and get some very stiff front springs and try those with current shock settings. From there go softer at the back until it feels better. If full soft at the back is still not enough then go harder at the front.

GORDON STREETER · 23 Jun 2008, 12:29 (Ref:2235624)

Basically its best IMHO to set all shocks to their hardest setting and try it for a few laps, come in and reset them to their softest and try it again. You will soon find out what suits the car and then you can fiddle with front to back settings to set the car up for your driving style. Whatever you do keep a note on what you do . If you make big changes for a start its easier to find out whats happening. No two drivers can always agree on a final setting to suit them ultimately !

rogerwills · 23 Jun 2008, 13:39 (Ref:2235709)

Its what they are supposed to do I thought.....

http://picasaweb.google.com/wills.ro...70913547835538

rogerwills · 23 Jun 2008, 13:50 (Ref:2235719)

zefarelly · 23 Jun 2008, 15:10 (Ref:2235780)

looking good for the cameras doesn't necessarily mean your going fast Roger

less of the cars lift wheels now than did then

basic Cortina set up seems to be 120-140 lb rear, 5-600lb front 7/8 ARB hard dampers in the dry and soft in the wet.

I know I'm not the quickest, but I'm not the slowest either !

Leo Landman · 23 Jun 2008, 19:28 (Ref:2236011)

Quote:

Originally Posted by esper

leo its vital to know how heavy you are and how do you sit in the car?

I weigh in at 77 kg and I sit on me bum, facing forward.

Leo Landman · 23 Jun 2008, 19:36 (Ref:2236017)

Quote:

Originally Posted by zefarelly

hard dampers in the dry and soft in the wet

Hard as in 'maximum', and on all four corners?

**Tim Falce** · 23 Jun 2008, 20:00 (Ref:2236041)

I may have missed something here but how will adjusting dampers stop wheels lifting, surely spring rates need changing.

terence · 23 Jun 2008, 20:16 (Ref:2236053)

Are you sure that you were not just launching off of the kerbing,I think I would be checking that first rather than changing anything,it seem's a bit unusual for the inside rear to lift.

Al Weyman · 23 Jun 2008, 20:30 (Ref:2236064)

If he had two way adjustable shockers I would have thought it could introduce a bit of wheel lift if too hard on the rebound setting. I dont know but I have heard of guys going harder on the rebound to get a bit of oversteer in or do I have this wrong as I have two wa adjustables on my car amd am not sure what way to go either.

Leo Landman · 23 Jun 2008, 20:34 (Ref:2236071)

Quote:

Originally Posted by terence bower

Are you sure that you were not just launching off of the kerbing

Quite sure. I can provoke it by going into a corner on a trailing throttle.

Falcemob may be right about the springs, but there's nothing I can do about them at the moment.

terence · 23 Jun 2008, 21:54 (Ref:2236159)

In that case Leo I think I would be inclined to play with the shocker settings,something like 4clicks off full hard on the front and maximum of 4 off full soft rear,you really dont have much choice,Falcie and Gordon are probably right,sounds more like spring related.

zefarelly · 24 Jun 2008, 06:54 (Ref:2236341)

agreed, stiffer front springs is what you need, the front end is probably diving and unloading the rear . . .my MK1 estate does the same when I go shopping quickly

LC driver · 24 Jun 2008, 13:04 (Ref:2236537)

Quote:

Originally Posted by zefarelly

agreed, stiffer front springs is what you need, the front end is probably diving and unloading the rear . . .my MK1 estate does the same when I go shopping quickly

Put an engine in the back Joe

esper · 24 Jun 2008, 21:23 (Ref:2236843)

Quote:

Originally Posted by LC driver

Put an engine in the back Joe

thats what you do from time to time when you have your springs to stiff at the rear. I wouldnt mention flat beaten beetles overhere LC.

GORDON STREETER · 25 Jun 2008, 18:30 (Ref:2237456)

http://www.flickr.com/photos/16345037@N03/1766974993/
Anyway what would I know about lifting wheels !

terence · 25 Jun 2008, 19:59 (Ref:2237524)

And not a launch kerb in sight Gordon.

esper · 25 Jun 2008, 21:13 (Ref:2237584)

Quote:

Originally Posted by terence bower

And not a launch kerb in sight Gordon.

no its just after the detroit locker came in.

zefarelly · 26 Jun 2008, 07:35 (Ref:2237781)

very impressive

http://i261.photobucket.com/albums/i...els-Gordon.jpg

Quote:

Originally Posted by GORDON STREETER

http://www.flickr.com/photos/16345037@N03/1766974993/
Anyway what would I know about lifting wheels !

terence · 26 Jun 2008, 07:39 (Ref:2237786)

I take it thats the original Zef!

esper · 26 Jun 2008, 08:09 (Ref:2237804)

Quote:

Originally Posted by terence bower

I take it thats the original Zef!

no the original has a bottle of larkins in place of the jack

terence · 26 Jun 2008, 09:21 (Ref:2237841)

Larkins? It's not strong enough.

GORDON STREETER · 26 Jun 2008, 12:52 (Ref:2237980)

Quote:

Originally Posted by terence bower

Larkins? It's not strong enough.

Come to think of it. I used to drink 15 pints a night, now I can manage 30.
Bob must be watering it down !

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