DIY GEO

[sdio]

Hi all,

I have always been using the string method to adjust the geo setting of my car with great results, however this was an elise for which we tend to refer to mm and not degrees as i see people referring to for caterhams.

Do you know how i can convert mm to degrees to work some meaningful figures on the catheram?

By searching through my old records i found two formulae we used to refer to for the Elises to relate mm to degrees but now i am looking at this again it doesnt make sense since 1 degree has 60 minutes but the formula gives decimals of a degree (100 decimals to 1 degree)

These where:
DEGREES( ATAN( CAMBER_IN_MM / ( RIM_DIA_INCHES * 25.4 ))) for calculating camber
DEGREES( ASIN( TOE_IN_MM / ( RIM_DIA_INCHES * 25.4 ))) for calculating toe

Cheers
Vagelis
Cheers

[JUPE777]

Trigonometry or download free 2d cad software. Diameter of your wheel as the base of a triangle and perpendicular line the length in mm's you want then you can check the degrees.

[JUPE777]

Here you go, trigonometry calculator.

http://www.carbidedepot.com/formulas-trigright.asp

[sdio]

JUPE777 said:

Trigonometry or download free 2d cad software. Diameter of your wheel as the base of a triangle and perpendicular line the length in mm's you want then you can check the degrees.

Thank you gentlemen,

I did done geometry/algebra calculations and sorted the problem out

[sdio]

Hi,

After having completed my cornering weight with the use of 2 digital scales i moved on to the geo setting and it ended up surprisingly symmetrical.

I now have 70mm under the sump, 22mm rake, -2.2 front camber, 0 Toe.
I will let you know how it drives once i will have it tested.

Caterhams are soooo much easier than elises when it comes to this...

[shrink1061]

Not that I know much about it, but doesn't 22mm rake seem a bit excessive?

Academy setup seems to be around 15mm and increasing that will only add to more overseer.

But then if its working for you, then it doesn't really matter

[sdio]

I will find out, anyway my problem is understeed not oversteer.

[sdio]

Oooooh yes!!

It now drives brilliantly.
Thank you for your advise people.