Been toying with the thought of widening the rear track of my 88 Formula track/autocross car.
Have custom built coil overs at the front and Koni struts with adjustable spring/perch at the rear.
I do not want to install spacers at the wheels. The rear wheels are 17x 9 and just clear the knuckle.
Thinking about modifying the strut to move it inward from the knuckle and be able to run a wider wheel.
Any thoughts?

I was thinking of lengthening the lower transverse arms to move the wheels out...but it seems a lot of work to gain approx' 3/4"......

You are talking about wider tires/wheels......which is different....

I believe both Arraut and West Coast have different length aluminum arms with adjustable ends that can be used- I wouldn't because they are metal-to-metal and I don't want to lose any more fillings......Yours' is a track car so it would probably be fine...

[This message has been edited by cvxjet (edited 11-02-2016).]

Arraut has a wide-track suspension setup which widens the track (hub-hub mesurement) by about 3" on each side, IIRC.

How wide a tire do you want to run exactly?

I am surprised the 17" x 9" wheels clear the 88 upright... What offset?
You can use something like this to relocate the strut:
http://www.arrautmotorsports.com/parts/kit-car


I am running 18 x 9.5 45et on the rear of my 88 with 285/30/18 tires. On aggressive corners the tire will rub the trailing link slightly as well as make contact with the wheel well liner in a couple of places.

Also as an FYI, I relocated the top of the struts inboard 1" and was able to get -1.0 degree negative camber dialed in pretty easy on the rear wheels with the stock track width, so in theory, you could push the wheels out 1" and not need to do anything with the strut (but would need longer axles).

quote Originally posted by cvxjet: I believe both Arraut and West Coast have different length aluminum arms with adjustable ends that can be used- I wouldn't because they are metal-to-metal and I don't want to lose any more fillings......Yours' is a track car so it would probably be fine...

The lateral links only see lateral loads and toe control loads. The trailing links take the beating from road irregularities. So for my setup, I run rod end lateral links and rubber bushings in the trailing links. This maximizes lateral stability and toe control w/o any significant change in ride harshness.

[This message has been edited by fieroguru (edited 11-02-2016).]

fieroguru, where did you get that extension for the strut?

That pic is from Bloozeberry but he got it from arraut.

I also run lower strut spacers . I made mine around 1990. I have many hard, fast (Street) miles on them.



The single most important thing you must do is keep the strut at the same angel as stock. This angel sets camber curve. Some adjustment may be needed to this angle to tune for things like lowering and every thing you change that's related to rear suspension.
Remember that the rears don't steer so there is no “king pin angle”.
Moving the bottom of the strut in 2” means you should move the top in 2” also. Or use 2” longer “A”arm/ lateral links and axles.
Or rims with less back spacing, cheaper but not as good of fix. I think the best way to go is to move in as well as out to keep bearing lodes similar.
On my 85GT/IMSA I could not go that far in, and clear the strut tower. So made some spacers to move in the max I felt safe at, then moved the top in 1/4” more than the bottom to help comp for the angel of the “A”arms.


I use a 17x12 rim W 315R17-35 tires.


https://www.fiero.nl/forum/Forum1/HTML/096777.html

https://www.youtube.com/cha...oJ3CMtWvgEok8R-n3XRg
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Sincerely
George

[This message has been edited by fierogt4e (edited 11-02-2016).]

quote Originally posted by fieroguru: The lateral links only see lateral loads and toe control loads. The trailing links take the beating from road irregularities. So for my setup, I run rod end lateral links and rubber bushings in the trailing links. This maximizes lateral stability and toe control w/o any significant change in ride harshness.

I agree with this. Also, I have a similar setup on my Fiero. Even with rod-end lateral links and Koni struts, the rear end doesn't feel harsh. Of course it's firm, with the Konis and stiffer springs. But I don't feel every little pebble in the road. The rubber bushings in the trailing arms soak up a lot of the harshness.

Best way is replace or modify the control arms to make them longer. You can also just order deeper dish wheels with a different offset. On my Lambo and Ferrari kits, I had 4" offset wheels. They looked perfect on the body. I had no problems at all with ill handling or worn bearings in 100K miles.

do you need longer axles with these setups?

Yes, you need longer axles to match the wider suspension.