Looking at rear ARB's for mine, there seems to be a choice of 2;

Whiteline - 20mm

http://www.gnjmotorsport.com/products/Whiteline-Adjustable-20mm-Rear-Anti%252dRoll-Bar-Fabia-5J-1.2%2C-1.2T-Si%2C-1.4%2C-RS-1.4T-Si%2C-1.4TDi%2C-1.6%2C-1.6TDi%2C-1.9TDi-%2803%7B47%7D07%252d%29.html

H&R - 25mm

http://www.briskoda.net/forums/topic/255056-hr-suspension-and-anti-roll-bar-group-buy/

As you can see there are 2 different thicknesses, so which is the bar to go for? What advantages would you get with say a 25mm bar compared to the 20mm?

The thicker the bar, assuming identical construction, the more it will resist roll. In turn, I believe this may increase understeer.

I used to have Cusco ARB's on my S2000 32mm on the front, 30mm on the rear. Transformation was nothing short of incredible

Stiffer rear bar will resist understeer.

This is why I'm going for the h&r option on mine.

Or Jabbasport bar like me

Or Jabbasport bar like me

How much approx. did this cost to supply and fit if you don't mind me asking? Thinking about getting one myself from Jabba next year

Its about 1k. You need either a milltek or custom cat back for it to fit haha. Think mines the only mk2 with one on.

Rear anti roll bars reduce under steer?

Its possible to go too hard , a harder bar may keep the tyres less planted on bumpy roads but are much better on nice smooth circuits

Ive got the whiteline one on mine and it transformed the handling. Made the car feel a lot more sharp and did help with Understeer. Am I not right in saying you have my old weitec Coilovers? Not sure how much of a difference it will make with them on because they are already really stiff.

Stiffen the back = reduce understeer

Stiffen the front= increase understeer

All basic stuff really.

"Stiffening" can be via springs with a higher rate and/or thicker ARB's.

Thicker ARB's can compromise ride also by reducing independence of operation of each side of the vehicle.

It's all about the best compromise to suit individuals,but never forget that the manufacturer has spent much time and money on developing the standard set up,any alterations may or may not improve on that,depending on what result you want.

Anti roll bars reduce roll the clue is in the name pretty basic really

http://auto.howstuffworks.com/question432.htm

This in turn can have a positive or detrimental effect on grip and grip reduces understeer

I understand how they work in reducing roll, and keeping the car planted in the corners, it was wondering what the benefit was by having a thicker or thinner ARB.

I have got your old Weitec coilovers on, and the car has stiffened up a fair bit, but still suffers from some roll, actually doesn't feel too bad on the roads that I use the car on, and also managed to straighten that bracket out too!

still suffers from some roll

Correct me if I'm wrong but isn't some body roll necessary for the car to be able to take corners? I mean how flat do you want it to stay?

depends on how much roll were talking about. The springs I have on mine have reduced the amount of body roll but there is still far to much body rioll left.

There will still be body roll even with coilovers and front/rear bars.

Regarding the H&R swaybar if understand correct from the photos do you need to drill through the axle in order to install it? anyone?

Below is the SuperPro bar NOT the H&R!

no drilling required. It fits the same as the whiteline bar iirc.

no drilling required. It fits the same as the whiteline bar iirc.

Hmm you might be right. Also I've found pics of the front/rear sway bar kit from H&R that is on group buy. (33325-3)

Hmm you might be right. Also I've found pics of the front/rear sway bar kit from H&R that is on group buy. (33325-3)

I'm confused now - the kit looks nothing like what SchuMi has on his car. I think we should make sure with Alex what kit is the correct one for the 5J.

Hey 32K...the bars on my car are HP bars (made by SuperPro)...not the H&R

Hey 32K...the bars on my car are HP bars (made by SuperPro)...not the H&R

Oh! crap! so sorry I complicated things thanks SchuMi!

Fixed the posts!

Looking at the H&R rear bar, it will bolt directly onto the lower end of the shock absorber - like an old Eibach bar I once had on my mk1 Octy vRS.

A much, much neater design than the whiteline.

Steve