I just replaced my original shocks with Konis, now I want to finish the rear suspension with a better sway bar. Is the 19 mm M030 sway bar a good choice ? Or dosent a rear bar do anything special.

 

The short answer is that the rear bar is very important. If you don't have a rear bar, or have a wimpy 14mm one, then the car will be more understeer-prone and harder to get the back end to rotate. The 19mm 968 m030 bar is a great choice because it is adjustable- depending on which bolt hole you use you can make the bar effectively "softer" and the car more stable, or effectively "harder" and make the car more likely to rotate. The NA 944 m030 rear bar is actually a non-adjustable 20mm bar available from 944online. I have one and it is nice, but I can't tell a major difference from the 18mm "sport" bar I used to have.

Sorry the short answer wasn't very short.

Very short answer: Yes, get the 19mm 968 m030 bar.

 

I have a 22mm rear sway bar on full-soft because it induces a bit too much oversteer for my taste set any harder.

I'd reckon that a 19mm bar on a stock suspension street car should be just about right. It'll probably understeer slightly at the limit (which you want on the street if you ask me) and will probably rotate nicely if you lift, without snapping you around.

 

100% agree. I have stock suspension with a 19mm m030 rear bar and it made a noticable difference. Middle setting on the bar was perfect for me. When driving at threshold it will produce understeer.

 

One note: no one here is mentioning the front sway bar. You need to consider what you've got up front as well. Not sure what the front sway bar size is on your na, but you should consider upgrading to a 944 Turbo/S2 front sway bar (non M030) if you are going to install the M030 19mm rear sway.

Given that our cars were engineered to have an understeering attitude, that is why I like the "+1 sway bar in the back" philosophy. IE: Stock turbo front sway coupled with the M030 968 rear sway. I used this setup with my 944S2 when I had a stock suspension. This worked well for the track as well as autocross, and it was fine for the street. With my modified suspension, I now have an M030 front sway bar and a Weltmeister 22mm rear swaybar set to a tick firmer than middle.

One caveat: your driving style greatly dictates your sway bar choice and settings. Like a little oversteer? Then a thicker rear swaybar or firmer setting on the rear sway is a good choice. Feel safer with a bit of understeer dialed in? Go with a smaller rear sway bar or a softer setting.

-Z-man.

 

so what are all these different sway bar sizes on M030? I always thought that it's M030 because of a 30mm in front, aparently I was wrong

 

Stock 944S2 / 944 Turbo sway bars: Front: 27mm; Rear: 16mm

M030 front sway bar (944S2/Turbo): 30mm

M030 rear sway bar (from 968): 19mm 3-way adjustable.

Weltmeister rear sway bar: 22mm adjustable.

Don't know the specs for 944 stock sways, nor do I know the specs for the 944S2/951 M030 rear sway.

Hope this helps,
-Zoltan.

 

I should stop posting when I've been drinking...Z-man is absolutely right.

I have a 22mm rear bar
and a 26.8mm front bar

Both work together to give me the handling I like. The adjustability in the rear bar is key.

 

i had no sway on the back of my 924S, but im about to add a stock 944 rear... 14mm i believe?
only problem is i dont know when my next track event will be, so i may not even know a difference.

clarks-garage has a chart that shows most, if not all, of the stock suspension setups. its listed in the shop manual under suspension.

 

Turbo S / 951 M030 is 26.8 mm.

Chris your oversteer is probably due to the small 26.8 mm sway bar with that 22 mm weltmeister. I run the front welt to match the rear which is not full soft.
Something to think about.

Also oversteer on turn in could be soft rear shocks.

 

The 944T sway bar was 25.5mm; the Turbo S, S2 (std and M030), and 968 (std) used the 27mm (26.8) front bar.

The 30mm front bar is originally the Turbo Cup sway bar, but also used on the production 968 M030 so they are available.

944T rear bar was 18mm. The Turbo S and early 89 Turbos also used 18mm bars, but mid-production 89Ts changed to 16mm, which was also used on the S2s (std and M030) and 968s (std).

There is a 20mm rear bar (non-adj) that is from late 944 and 944S M030 optioned cars. You dont see these too often, but I think they are still available from porsche NOS.

The Turbo Cup/Club sport rear bar is 21mm 3-way adjustable, but quite rare and no longer available from Porsche Motorsport.

 

Joe,

The car only oversteered with the rear bar sliders set about 1" from the end of the bar. Now that the sliders are set full soft, the car is very neutral with just a hint of oversteer to help the car rotate for the auto-x stuff.

I would get the 28mm front bar, but they want too much money for what it is. My front bar was free and the mounting hardware was under $20 IIRC.

 

Chris,
That is fine and I figured the car was balanced ok. It will require the rear bar to be softer, but if you get the balance you need don't worry about it. Over the years I have learned more and more about suspension set-up on these cars and despite all I have learned I feel I still know so little. It is really crazy how many combinations of springs, sways, shock settings, ride heights and alignments have an influence. Oversteer and understeer only begin to desribe what I car can do.

Just a last race I learn how imporant shock feel is. I had weak right rear shock and that was tough to find. I had issues of oversteer when trail braking into left hand corners. Right handers were fine, but left handers were off. Of course both left and right were fine power on. So I swap shocks left and right and the car handle much better since there are 3 places I take left turns with weight on nose, but only one right hander like this. I had been chasing this I think for a couple years thinking it was all me, but finally I figured it out. I gain 1/2 second just from that and now need to adjust my driving to gain back another 1/2 second that I could get just from learning to use that extra grip in left turns.

Crazy stuff...

 

Indeed. I hope we didn't scare the OP too much

I've always appreciated your input. Using the baseline camber and toe settings you recommended, I was able to achieve a near perfect balance in the car with only one slight adjustment (the slight rear bar adjustment). Along those same lines, I'm not buying R888's until you finish your "analysis"

Sorry to go so far off topic guys...it's been a long day.

 

so the 30mm bars and 19mm bars are what's desired? where do you get all this stuff from? trial and error?