30 replies to this topic

[MrSimba]

Right... the Braids are now sold & I'd really like to polish them up for their 'new' owner and leave them be, also I've a walshy day on the 23rd and I'd like to scrub the AD08's in there and see what they are really like! Also I'm not going to be able to have the geo reset before I go so need a 'temp' fix! Currently I'm on 205/45/16 - 225/45/17 & I'm going to be going to 205/45/17 - 235/40/17 My 'rake' at the moment is 10mm the difference is - front +25mm rear -15mm So... I'm led to believe (though stand to be corrected) that 1 turn on the Nitron platform is 3mm so I need to back the fronts off at least 8 turns to get the 17's in the rear as they are already going to be 15mm under is now going to be effectively 40mm 'out' so 13 turns 'backed off' I realise the toe and camber will be affected but does my 'maths' sound right? not worried about high speed stability as thats not an issue for a Walshy day, just want to adjust the platforms 'in balance' to do the day until I can get the geo properly corner weighted & set.

[MrSimba]

Or should I do the day on the Braids? the 'new' owner being a decent chap is quite happy for me to do this

[Darcini]

Or should I do the day on the Braids? the 'new' owner being a decent chap is quite happy for me to do this

Nah, if I were you I'd definitely do the day with the new wheels, it's a no brainer IMO

[MrSimba]

Lol!!!

[JG]

You can do the measurement yourself Simon. I'd stick with the 110 to 120 at the front and 120 to 130 at the rear (or any combination therefore with a 10mm rake). I wouldn't rely on counting turns. Stick the wheels on, measure from ground to chassis at the front and ground to middle undertray at the rear and keep adjusting it until its right. You'll get good at jacking it up, letting it down, moving it back and forth a few times to settle the suspension, measure again and so on. It usually takes a couple of goes to get it right all round.

[MrSimba]

Cheers James, thats good advise! Thanks again

[MrSimba]

Is 1 'full' turn on the collar about 3mm?

[JG]

Its a lot easier if you have one of these:

Not a very large investment at less than 2 quid

http://www.amazon.co...36942382&sr=8-1

That combined with flat ground and you can't go wrong.

[JG]

Is 1 'full' turn on the collar about 3mm?

I'd say it was a bit less than that. probably nearer 2mm

[JG]

The trouble is, you have to enjoy geometry (in the mathematical sense) if you want to move the collars by x to move the ride height by y, and even then it never quite works. Thats the case for the front anyway since the shock forms a triangle and becomes the hypotenuse. On the rear, collar adjustment pretty much equals ride height, but its still better to use the method i mentioned.

[CocoPops]

James is good at it He's like a whirling dervish whiz zing round adjusting each corner.

[kipper]

Just had a annual service at Plans. My friends there suggested that I should alter the rake front to rear, on my Turbo, to essentially flat front to rear. They measured what I had (120 mm front, 142 mm rear!) and brought down to 120 mm on the rear and 120 mm on the front. In their experience Tubo's run better when you have the ride hight front to rear, flat while Na's should have some rake. Any body found this as well? Dave

[jameso]

mine was defo better with 10mm rake

[kipper]

mine was defo better with 10mm rake

I was always under the impression that both the Turbo and NA had about 10 mm of rake this is the first time I have heard of no rake on the Turbo. Mind you Plans through their experience might have found no rake an improvement.

Always surprised when I go there at what they are up to...Graham showed me a set of suspension wishbones that he had made up for a couple of customers with very deep pockets, light weight wishbones saving 5 Kgs all round...however, at £300 a shot each!!

[jameso]

OEM on tubby is 140mm F 140mm R i think

[westie]

OEM on tubby is 140mm F 140mm R i think

Yep I measured mine this morning and it was the same (turdo)

[2-20]

Your difference +25 /-15 is on the diameter. You have to take half of that (+12.5 / -7.5) because the relevant dimensions are from the tire contact patch to the hub center.

[kipper]

Can anybody indicate exactly where to take the ride height measurment from. For the rear, is it from the chassis cross member in front of the rear shear plate? The undertrays are not good reference points. Also the closer the front and reart ride hide measurmernt points, the greater the overall effect of of say 10 mm difference between the two points.

[Arno]

Measurement points:

Front ride height: B
Rear ride height: A



Ride heights quoted by Lotus/.Vauxhall are based on a loaded/ballasted car, so with 75kg in each seat and 1/2 tank of fuel (aka. driver and passenger ready to drive).

Wheel alignments are usually also done with the ballast in place or only the driver's weight so you get the correct result when you're in the car and driving the thing instead of a static setup with nobody in the car.

Bye, Arno.

[JG]

Thats a not a very accurate diagram. Hang on, i'll go and take pics for measurement points.