Hi Guys.
I am after a bit of advice in setting up my AP1 for the track. Currently it is stock in tyres and suspension except for the addition of a set of aragosta coil overs. They seem pretty good with a firm spring rate and good adjustment of damping but as they came with the car I am not sure of spring rates. Problem is the car feels very unstable in the rear. A little bias to overseer is fine but mine seems to break away quite unpredictably and at much lower cornering speed than I would expect for it to get untidy. I have had the suspension set up by a local performance suspension shop and they have dialed in -1.5 camber on the front and -2.0 on the back. Total toe seems less than some people suggest here on the forums at about 1.3mm front and 1.5mm rear.

I am wondering if a stiffer front sway bar is a cost effective option and perhaps disconnect the rear bar or replace it with something softer (I hear a front Miata bar can be used and they are much softer than the S2k which will provide further front / rear grip balance. Also what is the rationale behind going with a lot or rear toe in. Is this just to counter rear bump steer in mid corner or is there something more to this.

Thanks
paddy

 

Really need to know more about the coilovers. Can you find more info on them?

 

Replacing coilovers isnt going to fix a bad choice of alignment specs.

You need a proper alignment. 0 toe front. The OEM Ap1 rear toe spec is 3mm per side, if you dont have enough toe in in the rear then yes the rear end will feel unstable

 

I had and 01 with the same issue. The has the 16 ap1 rims with hankook rs3. Changed sway bar to AP2 and feels way better. Much more predictable. If I decide to go 17x9 square I may do a Miata bar. Haven't gotten there yet...maybe by next year.

 

What damping setting are you running/clicks? if you run too much rear damping, the initial break away will be magnified under steering inputs. You want the rear suspension to move instead to maintain grip.

Yes, if your still running a tire stagger I found switching to any year ap2 rear sway (they are all the same) is the best one thing you can do short of having a proper alignment and proper damper settings. We have the stiffest sway bars out of any of the years, including the CR, and is the only years that has a stiffer rear sway vs front. If your already running stiffer suspension with the aftermarket coilovers, the last thing you want to do is remove traction with your factory size tires, by adding a stiffer front bar.

Factory toe in the rear is too much. I run 0.10-12 per side. Less then 30 total. I do also run bump steer correcting toe arms to limit toe correction under upstroke and am lowered about 2" which removes wheel droop, which also changes toe. The car is well balanced with -2.5 camber all around for my particular suspension set up and tire width stagger.

 

Hi guys,
sorry I didn't realise that I had to check my post for replies. Couldn't figure why I was getting no notifications. If anyone can read Japanese the details of the coil overs are here http://www.tpl.co.jp/aragosta/jp/datetbls/sp.html#Honda the only details I could determine is that the spring rates are 13 front and 12 rear which translates to 138 lb front and 150 lb rear which seams pretty light. I can get stronger springs locally but would be keen to know what rates will work. I can't decipher anything on the damping rates so any help would be appreciated. I have managed to get a heavy duty front sway bar and a Mazda MX5 (Miata to the US folk) NC front bar for the rear.
I have spoken to the shop who did the last alignment and asked why they went with so little rear toe and the response was "we set it up like an EVO" To their credit they are keen to fix things up.

Best regards
Paddy

 

the spring rate is 13 kg/mm and 12 kg/mm. Your springs are fairly stiff at 727 lbs/in and 671 lbs/in, not soft. But I'd look at addressing rear toe first.

edit: if my numbers are inaccurate I cheated and used the internet.. but 13k/12k isn't soft.

 

Your numbers are correct. Easy conversion from Kg/mm to Lbs/in is to multiply by 56. Nothing on that chart seems to indicate damping, but over/underdamped is easier to feel during use than try to interpret off a dyno. To piggyback off of Junky's comment, have you fiddled with the damping adjustments (assuming they are available)?

 

 

Hi guys
Yes I have played with the adjustment and firmed things up until there is no secondary bounce. This was about 6 clicks from full hard and there are around 20 clicks from full soft to full hard. There is a pretty good range of adjustment from quite a lot of bounce to very hard on full H. Thanks guys for pointing out my poor maths on the spring rates. I will have a go at sorting the rear toe and fitting the sway bars next. I have another meeting in 3 weeks so hopefully I will have it done by then and get a chance to check thins out.
Cheers
Paddy