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[Paul Blore]

Well done Alan, a good write up. I agree whole heartedly on both counts. People spend a small fortune, or a large fortune in some cases, building their cars but never get close to achieving the full enjoyment simply because they scrimp on two of the most critical areas of the build, the tyres and the setup.
To be fair, it's less of a problem on 289 Cobras, because there are more options for half decent tyres, but I dispare at the number of "427 Cobras" running around on BF Goodrich tyres, which are downright dangerous on a lightweight sports car in my view.
Having decent tyres that you can put your faith in and properly setup suspension increases the enjoyment factor immeasurably and having very recently driven over 2,500 miles in the Cobra to Italy and back, some of it on very demanding roads at a fair lick, I enjoyed every single mile, even in the occasional downpour and not once did it give me any cause for concern.
I also have Avon CR6ZZ tyres and Chris at Center Gravity also set my car up and I absolutely love it.

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[peterc]

I don't want to change too many things in one go. Currently playing with tyre pressures and shocker settings following the fitment of the Avons.
Out of interest Alan are you Rover or Ford engine and MGC or Jag rear suspension.
Weight wise you appear nearly 30 kegs lighter than mine also with full tank but your ratio seems the same as mine at 46/54%.
I have Gerry's front wishbones and Jag rear. It's the Jag assembly that's the heavy bit.
Anyway I will push on with my ex racing friend for the moment - it would be rude not to!
Peter C

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[Colin Newbold]

Nothing wrong with cart springs and a solid rear axle - its served me well on a certain red car for 3 years! In fact, I really can't believe how well the thing handles, you'd have to follow me to be convinced! Mind you, that might all be changed in my first 2 races of the season (Brands Hatch, Sat/Sun 30th Apr/1st May) as I've made significant upgrades to both front and rear suspension, pushing the rules as far as Mr Newey might

Anyway, enough about me! I started writing this with the primary purpose of applauding Alan for not only making the effort and expense to carry out proper suspension improvements but more importantly taking the time to update us all with his account. First class mate! Highly entertaining and informative both at the same time. Once again, this underlines for me just what a considerate bunch of guys we all are. T289R rocks! Super dope

Colin

[peterc]

Alan
I have just increased my ride heights to nearer that used at the time of the build. Tyre to wheel arch clearance should be aesthetically OK as its now equal around the tyres.
I now have 180 mm to the chassis at the rear immediately in front of the wheels and 166 mm at the front ( just before the chassis rises)
This relates to Stuart's reading of 6.25" = 160 mm
This is quite a bit less than your figures which got me thinking what size tyres are you on as that would also affect the position of the chassis to the road.
Mine are 215 at the front and 245 rears. If you are running the newer pin drive wheels then I expect that you are on 235's at the front and 275's at the rear. This would immediately give you 60% of the difference more than my set up.
E.g. 12 mm front and 18 mm at the rear.
This makes the numbers more comparable. I certainly can't afford to raise the car anymore at present. I'll recheck when the new front springs have been exercised a bit.l

Looking at your before and after figures I'm not surprised you noticed an improvement as the camber difference between each side would cause the car to want to deviate front the chosen route.

Talking of which my next job is to check the camber. Personally I'd probably go for a little more negative than you have chosen.

[Paul Blore]

I think Alan's camber is about right at around half a degree Peter for a road car. I don't think you'd want any more than that on the Avons. I ran more than that with the Goodyears, but reduced it when I changed to the Avons.

Paul

[peterc]

Thanks for the comment Paul.
I have run nearly 1 degree since the build and didn't notice any problems last year after fitting the Avons. I like the turn in on a negative cambered bend. In Wales I remember David being surprised at some of my cornering e.g not braking.
I 'm just chasing my friend for his camber gauge and then perhaps I'll ease it back a bit.
Just had the first run of the year. The new front springs from Gerry seem a bit hard the car doesn't manage the poor undulating B roads so well. Already backed off the shockers as Gerry suggested so might drop the tyre pressures down to 25.
Some tweeking definitely needed.
Peter C

[Roger King]

I have always run -1° camber on the Hawk and the Mustang. I have set the Kirkham up as negative as possible, which is tricky as the standard setup is +1°.
Not sure why your camber settings would be affecting directional stability - castor or toe-in, yes...* and you really can't judge someone's braking rate by the brake lights! My Mini's only came on when you were standing on the pedal with both feet until I fitted a Harley Davison brake light switch (yes, really, direct swap).
There is an excellent design for a foolproof camber gauge by Gerry in the members' area somewhere using a cheap spirit level and some screws. I used it for years until I found a CG4/5 on ebay.


*sorry Peter, just read your post properly and you mean the difference between the old side-to-side readings, not an overall change.

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