Anti roll bar size

[randomspeedfreak]

going to order a set of powerflex bushes for the car soon,
ill get the m3 excentric ones, but should i be getting a larger front arb and getting the larger bushes for it?

or should i just get the size of arb bush i have atm (16mm? i think) (1990 316) and leave it.

what im getting at is is it worth uprating the front arb, bearing in mind i currently have konis with camber, and am probably diying some harder coilovers soon

cheers,
Matt

[capri_rob]

You may as well uprate the ARB to a thicker one if you're doing everything else - IIRC the 325i has a 20mm bar and should be available secondhand pretty cheaply if you don't want to fork out for an Eibach or H&R one

[anton89]

It all depends on the new coilovers your going to get and the spring rates. If your going to be choosing a set up to give you optimal grip in the corners you want the camber wilst cornering to be 1.8 negative. a stiffer arb and a stiffer spring rate will meen you need to run a higher static camber to compensate for the small camber change in roll. this adjustment can only be done if you have adjustable top mounts. so if you want to corner as fast as possible i would recomend

1.choosing your coilovers and spring rates.
2.look into the amount of roll you are getting.
3.Find an ARB that adds the extra stiffnes the springs dont to avoid roll.
4.Adjustable top mounts. without these spending money on the above is a lucky dip.

otherwise all youre money could be spent making your car corner slower than it does now, stiffer unfortunatly is not always better. Its system dependent.

However if all your after is for the car to FEEL faster then make it as stiff as you like.

Polly bushes are great at reducing play in the system but should be used to help isolate roll control to the ARB and springs.

Sorry if its a bit mombo jumbo but roll bars, spring stiffness poly bushes are only there so the camber angle can be completely controlled

[randomspeedfreak]

It all depends on the new coilovers your going to get and the spring rates. If your going to be choosing a set up to give you optimal grip in the corners you want the camber wilst cornering to be 1.8 negative. a stiffer arb and a stiffer spring rate will meen you need to run a higher static camber to compensate for the small camber change in roll. this adjustment can only be done if you have adjustable top mounts. so if you want to corner as fast as possible i would recomend

1.choosing your coilovers and spring rates.
2.look into the amount of roll you are getting.
3.Find an ARB that adds the extra stiffnes the springs dont to avoid roll.
4.Adjustable top mounts. without these spending money on the above is a lucky dip.

otherwise all youre money could be spent making your car corner slower than it does now, stiffer unfortunatly is not always better. Its system dependent.

However if all your after is for the car to FEEL faster then make it as stiff as you like.

Polly bushes are great at reducing play in the system but should be used to help isolate roll control to the ARB and springs.

Sorry if its a bit mombo jumbo but roll bars, spring stiffness poly bushes are only there so the camber angle can be completely controlled

perfect answer thankyou. i already have ajustable top mounts, and i prefer to avoid roll using spring rates rather than arbs, as i dont mind the sharper breakaway from harder suspension (grew up kart racing!) ill probably go for a ballpark rate and leave the arb be, ive got to get these bushes now im getting sea sick driving this thing about!

[anton89]

if you have adjustable mounts then things can only get better. as long as your camber hits the magic 1.8 in hard corners itll feel a world apart from what it did. Glad to be able to help.