Advice Needed Re Sussy Arms And Alignment, For Circuit Work

[Touge Kyousou]

Hi SAU,

Once again looking for your expert advice

I'm chasing lap times in an r33 gtst, specifically at wakefield park in nsw (i'm on a personal quest so no instructors and car must remain street rego'd)

At last outting, it got 1:09.6 and was good for 9 flat or really high 8 but i ran outta fuel =/

Vital specs during this outting were:

-gt2871r for 260rwkw

-bc br coilovers (has not been corner weighted yet)

-adjustable front/rear swaybars and f/r strut bars

-minor weight reduction

-Hicas lockbar and fairly tight shimmed diff

-Usual minor brake upgrades like pads,rotors,lines, standard calipers

-gtr spoiler set to max, no front undertray, raised bonnet

-Nitto nt-01 245/45 on 8" front, 255/40 on 9" rear

-Mild alignment (from memory, around 1.8 neg camber front, 1.6 neg camber rear, castor at 7 degree via offset bushes, 0.7mm toe out per side front, 0.5mm toe in per side rear). Car still has all stock arms

Since then, the car blew the turbo so that was replaced and is now running bit over 300rwkw, rear tire replaced with 275/45 on the same 9" wheel...

I'm wanting to get into low 8's or maybe really high 7's and now wanting to dial in a much more aggressive alignment and realise i need to get a bunch of arms for this?

QUESTION:
What arms do i need to get for roughly what alignment and are there any other mods or setup i should change ?

Or do all the factory arms do a reasonable job and i'm wasting my time doing all/some of them ??

Is there anything else i should be looking at ? I'm aware of the need for f/r undertray and will have a go making some out of signboard when i'm bored...

I've been thinking of doing subframe bush collars as well, if that makes any difference.

Car will be getting 'set-up' at east coast suspension properly if arms were to be done etc.

THANKS

TL;DR

Wants much fast, is suspension arms gud and which ones to buy/adjust? Or save moneyz

[zebra]

You are nearly there

A better set of tyres would just about get you there, so think A050's or whatever the good Hankooks are (z221 or something)

Have a look at ssxricho's build, he does 1.05s around wakie.

[Duncan]

It's unlikely you need aftermarket arms, you can get pretty much any sensible alignment with just adjustable bushes in the factory stuff. Also, depending on the arms you get they sometimes have a habit of breaking unexpectedly....

[Touge Kyousou]

Thanks for the replies Zebra and Duncan!

Regarding tires, i forgot to mention i'd like to stay on the nt-01s... so far the car has been roll on and off track with no hardware changes and wanting to keep it that way. I can't afford to run the a050's on the street haha however am happy running the nt-01's on the streets when i do (once a week or so) drive the car.

Yes, very aware of Richo's 33 and have been following that closely - i sent him a PM earlier. Think i'm in love haha

Will look into the adjustable bushes thank you - though i think the end price of doing adjustable bushes vs arms might be the same?

Point taken on arms breaking though - that would suck!! I was looking at the gktech brand which seem to be decent rep and quality/strength.

Now i'm off to drive the thing to go get pies

[Duncan]

oh yeah, that's another thing. less pies = faster laps

arms are not a simple choice because the cheap ones invariably use cheap rod end bearings which flog out and start knocking reasonably quickly in road use....

[GTSBoy]

The main adjustables I would consider would be front caster rods. Having proper control of the fore-aft movement of the front suspension is worth it.

[djr81]

TL;DR.

What spring rates do you have in the things? Sway bars?

Basically more neg camber at the front is a good idea. You cant get on the power if you cant turn the corner.

[Roy]

So you have shimmed the std viscous diff?

I am with Duncan, no point goign arms etc if you can get the alignment you need. Though given the tyre you are running, and not knowing the spring rate you are running, I would tend to try and run 2.25 front camber and 1.25 rear camber

From there...diff....at a minimum something like a KAAZ 1.5 and then I woudl suggest just driving the wheels off the car. The laptime is always in the driving

[Touge Kyousou]

Thanks for the replies everyone!

Have booked the car in at east coast suspension to get it all properly sorted and also corner weighting. I've told them how the car behaves and what i want it to do.

Following the advice, i haven't purchased any arms but am considering the cusco front upper arm purely for camber adjustment. I just had a look at the car and the front camber from my eye appears to be over 2 degree neg already though..

Will grab the subframe bushing collars tomorrow and install them though.

For spring rate, it's the BC BR coilovers so spring rates will be the 8/6kg standard on them.

Swaybars are whiteline adjustable units and currently on the softer settings - have asked eastcoast to look at this during the setup. I didn't have it on the more aggressive settings as wasn't sure if it was a good idea to force the bar around to reach those holes...

Front caster currently is on 7degrees posi, via offset bushes. From what i've read this seems to be pretty ok but i'll keep an eye out for a good deal on tension rods.

Yes, diff is shimmed fairly tight (so violent on the street haha...), it was a stop gap measure as at the time i didn't have money for a proper mech diff.. thanks for reminding me Roy , gotta add this back to the list.

Definitely try and drive the wheels off the car when on track, previous turbo blew on track

Thanks again everyone

Edited March 9, 2015 by Touge Kyousou

[Roy]

I used East Coast suspension many years ago when I was still living in Sydney and they know their way around cars ... but just be sure they know what you use the car for. I told them it needed an alignment after I had installed the HICAS removal bar and the little bus was my fun daily-track car. The next day i went to Wakefield it was the worst the car had ever driven.

When I questioned them about why the car was all of a sudden the biggest understeering POS we came to realise they were expecting me to bolt on a set of DO1Js or something assuming that nobody tracks their car on the lowly Falkens I had on the car. LOL so the 2.75-3 deg front neg camber and something like 2deg rear neg camber had no chance of ever working on the crappy Falkens I used to run. It was waay too much camber for the tyre I run and grip I ever hoped to generate

So ...it is only a one off thing but was more a poor communication thing between both parties. Have an idea of what you want re an alignment before dropping it off. I had assumed they wouldn't wind in almost a degree of more neg at both ends when all I wanted was mostly a toe adjustment of the rear and a once over all the other settings