AST spring rates for road use
 

Got the AST coil overs fitted, they came with 60 / 50 springs.

These are a hard ride - car is a daily driver - and harsh over potholes or speedbumps!
I am worried about excess load on mounting points / chassis, and my seat!

Any thoughts?

Would I be better off with 50/40 springs?
The top mounts need replacing with adjustable ones soon to get right camber after lowering the body so would do both jobs then ...

Do the spring rates work best when one end harder than other? ( 60/50 or 50/40 ).

Cheers


Any one wanna PX springs??? Or buy a set of 1500 mile old 60/50 coil over springs for ASTs?

The 60/50 are a full race setting IMHO.
50/40 is much nicer and I'm glad I changed back from 60/50 at the start of the season.
The chassis is much more compliant when the road is not a billiard table.

Some run softer, and it would be a nice experiment to try 40/30, almost stock rate for a classic, but with the AST damping to dial things in a bit more focused?

I am considering going back to single adjustables from the 3 ways just for simplicity.

The springs from Curtis at Powerstation are not too expensive, and iirc the springs from Rob's units are near new so you might get a p/x for them?
Give him a call.

Cheers Graham

Rob's old (!!) AST's & springs were fitted with the STi top mounts and lowered to the level you gave me, 4 wheel aligned and it corners super now! Lowering it meant it was hard to reduce the -ve camber, hence the need for adjustable top mounts!

I think i'll try the 50/40 springs and let Powerstation do the work and set it up.

Thanks

Neil


{to paraphrase a TV show .... Save the STi ... Save the World! }

If you ask me, Subaru got it right with the STi 4 then after that it went too hard. The STi 4 spring rates are about 200/175 lbs per inch. Not sure what that is in new money.

Adjustable top mounts are essential, and you are missing out on a lot.
With lots of additional caster available, the understeer will dissapear, then the real hard cornering will be available with ease.

Graham, which top mounts would you recommend for road use?

I have used two makes.
Noltec which gives a very wide range of caster and camber and the excellent precision AST's which are still on the car.
Only for new age at the mo are the new Whiteline tops, very similar to Noltecs.

Both will allow the adjustment but there are tricks to play to gain a bit more from the tops/camber bolts, but all alignment techies know this.

Thanks. Are the Noltecs significantly worse than standard STi units in terms of NVH in your experience?

Also, would you care to share your tricks for the home camber / caster gauge user? :) Thanks

You should have tried the 90/75 springs!

I have 53/49 on my exe-tc's and if I dial the rebound back they are fine on the road, if that is any use to you.

Rob.

The bearings in the Noltecs are noise free.
I put a small drop of engine oil into the bearing every month to keep them smooth and fresh.
Remember i don't drive the Sti in the winter.

You simply put the left one into the right of the car and the right into the left. This will throw the bearing back and towards the centre line of the car so maxing caster and neg camber.
Some then trim the excess canber back to 2 to 3 drgrees using the camber bolts. Depends if you want a lot of caster for under steer. You will get comments about that!

I have been through quite a spectrum of angles in the 4 years of looking for the perfect chassis which I now think I have. (to my taste and use)

I am sure others will say theirs is better. OK, but I'm happy with mine!

I would love to try a few other things, but the car's for sale now.

Hehehe, no ta Rob, these are hard enough!
Now I don't personally mind the hard ride, although it could throw the car off line under very hard use, but thinking of the top mounts and metal panels, I'd like them to stay as they are and not bend! The seat gets enough of a hammer when we go over a speed ramp!!!

N

I think I'll go for the AST's.

Graham - would Curtis etc. at PS know to swap over the top mount positioning or would i need to advise him of it?
The alignment place who did the 4 wheel alignment after I put on the ASTs said I had about 1.8 degrees -ve camber ( couldn't go lower as no adjustable top mounts and as it is lower height ... ), and that would wear inner edge of tyre quickly.
3 weeks later MOT place said tyres were wearing on the inner edge!

I need a good fast road set up with no play and good feedback, but not too twitchy or too tyre edge wearing.
What's a good compromise? on SNET it used to be the Prodrive settings ...
whats the view now??

Ta


N

Curtis knows ALL the tricks.
I ran (Rob still does too I think) 3 deg negative for the hills with radials all round!
The 60/50's threw my car round and that was why I went back to 50/40.
The big springs Rob had were really nasty imho. His car look awful on the hills. Rather better now!

When i did have neg 3 deg, the tyre wear was even. I suspect the tracking is out. Get Curtis to do the lot and find out what real alignment does!

I run a lot less camber due to crossply Avon tyres 'cause I'm not a rich kid like Rob!

Mailed PS for prices and advice!

50/40 springs, adjustable top mounts, adjustable PU bushed rears lateral arms.

All this for a road car!!

Tell me about it....:norty:

Are PS open?
 

Mailed Powerstation twice last week ( 5th and erm .. 8th Sept ) to spend some money with them on parts, fitting and setting up/alignment but not had a reply?
Is it always this bad e-mail wise, or should I try again to phone them?

Best call on phone. Emails veryveryvery slow.
Go to Curtis direct.

Just spoken to Curtis. He has been away testing for customers, there now!

E-mail worse than slow!

Do I just ask for Curtis when I ring them, usually get Dirk or Rich ( I think! ).

Ta

If you call on the IVR, it gives you an option to speak to Curtis.

Banny