jasonius

iTrader: (1)

What are the down sides of having ARB's that are too stiff..? (all other things being equal, ie front and rear balance).

Only asked as I've recently fitted a whiteline 22mm adj read ARB to my 05 WRX (already had droplinks) and used the middle hole. The oem bar was 20mm, not the 18mm as people seem to think when advising the use of the middle hole, so although the car feels a bit tighter and handling on the limit is neutral (easily balanced on throttle) I'm thinking of trying the 'shortest' hardest hole setting. I know this will probably lead to excessive oversteer but if not are there any other downsides to going stiffer..?

BTW The wife recons stiffer is better but she know sweet FA about cars..!

Sorry about that last bit..!

Jason

911

Its summer time so you are forgiven...

Try the stiff setting, the difference between the 3 holes is not that pronounced imho, but it gets the car a bit nervey close to the limit.
Graham.

jasonius

iTrader: (1)

Cheers Graham,

It is very predictable at the moment so trying the the hardest setting is a bit of an experiment to see how stiff I can get the back end without loosing the stability.



when you say nervey do you mean sudden oversteer..?

911

No, not really.
The rear end just feels unsettled and very prone to lift a rear wheel like a Golf on the limit or posing for a magazine shot...

This obviously breaks traction/wheelspin, all of which hampers progress.
I ran for about 18 months on the hardest bolt hole but the car as a whole is much nicer on the middle hole by far. The softest hole is not that much different on the road, but changes things quite a lot on the track (sorry, hill climbs).

As ever though, the tuning of the chassis is a compromise and different for all of us, but I bet the 'hard core' here end up on the middle hole in the end after all the experimentation.
The effect of tyre pressures cannot be ignored either as to the general response of the chassis under extreme situations, and are worthy of experimentation. I have been surprised at some of the benefits to the settings I have tried recently, especially with my new AST units.
I have seen (felt) benefits in dropping pressured down to 26 psi all round on radial Kumho road tyres. I used to run road and track at 33 cold. The 26 allows a much quicker heating of the tyre from ambiant.

Probably a bit off your question now, but a facinating subject, (sorry)

Graham.

jasonius

iTrader: (1)

Actually I've always taken the tyre pressure balance as very effective way of helping fine tune the chassis balance. I usually run slightly higher pressure in the rears (31psi cold v's 29psi cold front) and found (even before adding solid DL's and ARB to rear) that this helps remove a lot of understeer. Only problem I find with lower pressure in the front is the outer shoulders (OEM RE050) take some stick when really giving it some..!

As always, very interesting..!

911

What tyres are you running?
I have Kumho V70's 205 16 45 which are very low profile. The wall stiffness is fantastic and the tyre wall 'square' to the rim. At 26 psi there is no tyre wall curling at all under very hard cornering indeed.

The car behaves so much better on 16's than the P1 17's I use (with Kumho V70's) for the road.

Graham.

jasonius

iTrader: (1)

oem Brigestone RE050's 215 45/17, which AFAIA have a relatively stiff sidewall..?

I've only noticed this once recently since 'testing' the r ARB and 'exploring' the limits on a large 'abrasive' car park..! Probably more due to extreme circumstances not really reflective of hard fast road/track use..?

Graham, whats your opinion of the effectiveness of strut braces (on newage) scoobs..?

911

When i was forced to remove my top front Sti brace because of the V8 TMIC, I noticed no difference at all.
Infact the car is quicker, but it did gain 80 bhp at the same time!

Personally, I think they are marketing Bling.

Graham.

austen_wrx

I have upper and lower front braces, i definetly think they have sharpened up the turn in and made it feel tighter. No where near as much as adding the ARB, but has done slightly. The rear strut brace does absolutely bugger all!! I think it would definetly help a wagon, but there is no way that bar can do any more than the great big cross section of the rear shelf/seat back.