Looking at fine tuning my setup on my Newage STI

Current mods are:
BC coilovers
24mm rear ARB
22mm front ARB
Drop links (the C shape ones)
JDM front trut brace
Fast road/track geo

I'll be adding an ALK soon, possibly the front roll kit aswell.

On a recent track evening I had more understeer than I wanted, although it was a greasy track.

BC's were on 25 clicks front and rear, front ARB on soft, rear ARB on medium.

What settings would people recommend I look at with the BC's and the ARB's?

Anything else I should look at?

 

Hi Gary

If your car is lowered I would add Roll centre/Bump steer mod,its worth the money and on our wagon this has transformed our drive

Can you please post the yours geo settings?

Jura

 

Cheers mate

Will dig the geo settings out, sure I have them somewhere

 

Deffo get the ALK and roll centre/bump steer mod done then get the Geo done. I have powerflex bushing throughout and tightens things up nicely. As if your bushes are worn then the geo will alter as soon as you move the car due to softer bushes.

 

how much are the powerflex full kits mate?

 

If you're getting understeer, then two things I would look at - ride height & front roll resistance

A 22m front bar, set on the firmest of the two settings, will increase front AND rear end grip as well as rear traction in most situations. Sometimes this is perceived as increase in understeer, but the reality is that the increased rear traction can now 'push through' the front end grip. The overall grip will be higher and the car will have a more benign balance.

Lowering. If you have a fair bit of lowering, then you will have too much front roll and therefore a possibility to hang onto the bumpstop on the outside front during corners. While this is a good reason for firming your front arb setting, it's also a good reason for considering roll centre correction, but all this depends on how much lowering you run. A pic of your car static and mid corner would be good

But I suspect a little understeer would be dialled out with a firmer front arb setting

 

Excellent, that is very helpful.

Hopefully these pics will be handy to see how low it's getting....



and normal ride height (it is pretty low)....



I changed the rear ARB yesterday to the firmest setting, and it certainly feels more positive, i may have to change the front setting aswell.

 

Camber bolts F&R

And stiffer bushes/mounts Make sure when you get the ALK you go for KCA359M which is the Motorsport bushing rather than the ***** bushing

 

Similiar to Moley on the same car - nice to see peoples responses on what the possibilities are to reduce the common understeer on these cars.

I have:
BC coilovers
Whiteline rear ARB - set on medium (i think)
Whiteline ALK
Drop links (standard solid ones, advised not necessary required to change)
Cars lowered on the BC's but not that low IMHO
Fast road/track geo.

Interested in the roll correction kits, struts, front ARB (???) etc

 

Almost certainly, your understeer will be down to the amount of lowering.

The roll centre will have moved very low indeed, probably below the ground. Normally this does create some strange handling characteristics as well as the distance between the COG and RC being a bit on the high side, increasing the tendency to roll at the front, not to mention going into positive camber mid-turn, and resting on the bumpstops. With your low ride height, you are already deep into the positive camber arc of the strut/control arm. You will have very little grip on your outside front wheel as soon as you turn as you'll be driving on the shoulders of the tires the whole time. You may actually experience some coil bind or full engagement of the bumpstop on that outside wheel leading to a large increase in spring rate and more understeer.

A roll centre kit is a must at that height (along with firming up the front arb). Firming up rear roll resistance does help reduce understeer, but in your case doing that is trying to compensate for what the front is (or not) doing

Personally I would run the front a little higher, at the expense of looks, for better handling and increased grip levels

 

Thank you, that's certainly a huge help.

The front was higher before, but I was advised to lower it slightly, and in doing so it made the turn in much sharper. May lift it with the new settings though.

Definitely going for the roll centre kit, and after a spirited drive this evening putting the rear ARB on the firm setting has made a big difference.

 

Also, what kind of settings should i have the coilovers on?

I currently have the same firmness front and back, but should one end be softer/firmer?

 

I set my BC ER coilovers up based on a "baseline" provided in a review I'd read, and the fronts are setup stiffer than the rears. It feels good, but not really got anything to compare it to!

 

Haven't seen anyone mention the "free castor mod" ? Or how about rotating the coilover top plates for more castor also? Should help front end feel and turn in?

 

what is a roll centre kit who sells them?

 

It basically comprises of Track Rod Ends and Lower Balljoints which are taller, pushing your control arms back down into optimal range for the geometry when on lowered suspension... or something like that.

Popular kits are whiteline and super-pro, I've got the superpro one and can't complain - seems like a quality kit.

 

Good call, however, castor mods give more subtle improvements and always the more dramatic changes can be gained from arb's, whichever works is sometimes down to real life

 

Every little helps I guess

 

Don't forget a wet track will also give rise to understeer through loss of front end traction. Also what offset and size are those wheels, what tyres are they and what was diff set to?

 

The castor mod with rotating the top mount is not that simple. You need to swap the topmounts over from left to right to get them to do the adjustment.

 

I think Demon Tweeks have the prices on their site as a front kit and a rear kit. I am not sure if you can buy straight from powerflex. I sourced mine over a month online using this site and fleebay to get everything I wanted at the best price.

 

Funny you mention that as I thought that. However, I gained 1.2deg caster / castor (not sure which spelling is right...) just from rotating the top mounts. So it looks like the below:



What more would there to be gained from swapping them over from side to side?

Thanks

 

Setting the front too stiff will make you understeer more too.... Play with it bud... althought front has to be a bit harder than rear as its heavier .... suspension has to work , so making a car too stiff is not necessary a good thing. Depending on the tracks surface it can start to skip , loosing traction. Our non dccd boxes with a **** front diff is not a helper either. I had to udjust my approach/driving style to eliminate/get rid of it a bit.... They just doesn't like when you drive them smoothly. .. my personal experience. I was faster in a more aggressive way in and out of the corner... Smooth application made me to slow alot and coming outof corner gradually pressing the axelearor made it understeer to the outer edge of the track. Sorry for the broken english , hope that helps...

 

Jason's comments may help at 1min 40.

 

Just for a bit of info. I did the free castor mod and just had it realigned this morning. Gained 1deg castor for a bit of moving around. Not bad at all.

 

I always wondered the same, I get the rotating bit but I've also seen people swap them over which I can't work out why.

 

Cheers for the comments guys, certainly gives me a few ideas.

I assume the 'free' castor mod will also work alongside an ALK and give more castor than just doing one of them?

 

Yes doing them together gains even more. I plan to do the ALK next...

 

Very interesting to know that - rotating the coilovers allows a little more castor. I know what I'll be getting done at next at my next alignment

 

5min job as well. However you do lose some camber adjustment.

I want to know if it's worth swapping the top mount plates from side to side. Or what it will gain anyway?