suspension Seeking advice and 924/944 parts for rear sway bar conversion

[XLR8]

Hi all, I seek to perform this rear sway bar conversion to my '81 924. 

I have the 20mm front sway bar in place, and standard springs/height and shocks all round. I'll be upgrading them over time.

The car understeers in tight corners right now.

Is the 14mm the best compliment to the 20mm front bar, or should I pursue the 18mm from a later car?

Will the 18mm make the car too "oversteery"? 

Also, does anyone have the following bits available?

1. Rear sway-bar.
2. Removable portion of the mounting brackets that hold the bushings to the torsion bar housing.
3. Bushings (if you don't have these - I'll manage).
4. "Dog-bone" drop links and bolts.
5. Extended eccentric adjusting bolts that hold the sway-bar to the trailing arms. 

Thanks for the advice! Appreciated.

[Timm]

I personally find that the rear 18mm bar is a good match to the 27mm front bar, for a neutral handling car.

This is on my 944 turbo with aftermarket suspension and a square tire setup. You may find that a different balance in sway bars suit you.

Greg944 is selling various front and rear sway bars, and probably has all the mounting hardware you need as well.

 

[XLR8]

Timm, you are a legend!

Thanks. I have spoken to Greg944 and we're in discussions about what may work.

Being 150-200kgs lighter than a 944 Turbo, I am thinking a 27/18mm setup might be too much. That said, the 20mm on the front at the moment doesn't seem to be doing much at all ...

Greg and I are trying to work out if a 27 (it's hollow I believe) will even fit up to a '81 924. Not sure about that.

 

[Timm]

I'm not 100% sure, but I thought all sway bars were interchangeable between all 924/944/968's, providing you have the correct mounting hardware.

I think you would be happy with the 27/18 combo on your lighter car, provided you have a square tire set up. I am reasonably happy with them on my heavier turbo, the balance is perfect, but it still has a little more body roll than I would like. So when I have the spare money I want to upgrade to the 30/19 combo from the m030 968, or maybe even an aftermarket set.

Bear in mind, your spring rates front and rear will also affect the car's balance. You need to have sway bars that work in conjunction with your weight distribution, tires widths and spring rates as a whole package to figure out what handles best for you.

[XLR8]

Good advice Timm. We have such horrible roads up here that I am not (yet) keen to lower the car, or stiffen up the springs/TBs. I am hoping that stiffer sways will be a good start.

Certainly the current mild understeer leads me in the direction of a new rear sway (as a minimum). 

[Timm]

Oh, if you just have stock springs/TB's then you can definitely go for some big sway bars I reckon. I have stiffer springs, with helper coil-overs at the back and I still want larger sway bars! I'm not very low though...no point as it's also a daily that needs to get into driveways etc. Also, when lowered too much the suspension geometry isn't optimal anymore, and worse still, the front ball joints can bind and crack the aluminum control arms.

Another thing to help combat your under steer problem is to dial in some camber in the front. I run neg 3 degrees, but I needed camber tops to achieve that. Not sure how much adjustability there is on stock 924's, I assume they have the same eccentric bolt to adjust camber as the 944 does.

You can also have a little toe out on the front to help turn in, but that will increase your tire wear quite a bit, more so than a bit of camber.

 

[XLR8]

I am hoping so Timm. There's a fair bit of body roll now, but the local roads dictate some spring compliance. I am also still running the 14" 4x108 standard wheels, and with the grunt I have available (very little) I can't really see the value to going over the top in the suspension department.

Maybe later, if/when the EFI and turbo happen ... 

I owned a Volvo turbo wagon some years ago, and a set of Bilsteins and matched and heavier sways (on the stock springs) really made a massive difference. The handling of that 1700kg monster was really great.

Once the sways are bolted on, I'll level the 924 (she sits about 15mm high at the rear now) and get a full wheel alignment. Your advice on this topic will be of assistance. Thanks.