Adding rear sway bar to an early 911
 

So my 69 911 E was upgraded in early life from the hydropneumatic struts to bilsteins. At that time, a 20 mm through body sway bar was added. I am currently having the car rebushed, lowered & cornerbalanced and am thinking about adding a rear sway bar.

The car has a nice & torquey 3.0 transplanted in it so I figure theres more weight hanging over the back axle and am considering adding a rear sway bar. A 20 mm rear sway bar was included with my deal on this car and it came in the front trunk. I think it fits a later car so I suggested to the shop that's doing the suspension update that we could use this bar. He suggested that the car would tend to oversteer with a rear sway bar and recommended that upgrading front and rear torsion bars would give better handling with the 3.0 than a rear sway bar.

When I ordered Street kit 1 from Elephant racing, Chuck asked whether the car tended to understeer with only a front bar on it. Since I havn't driven the car in the twisties that much yet, I havn't really noticed.

The shop doing the upgrade is Musante Motorsport in Windsor, Ct. He deals exclusively in Porsche. I'm dealing with the owner himself Chris who is a race driver himself. (He's up at the track in Canada this weekend). I trust his judgement from his years of track experience but wonder what the technical reasons for his suggestion are?

I realize that the early cars came w/o rwar sway, but the factory added them as years went on. Was that because later cars are heavier than long hoods?

I know that 911s have an oversteer characteristic which is certainly desireable on the track and a little less so on the street. What am I missing?

He is absolutley correct.


On some tracks the rear sway bar is deleted to reduce oversteer which is not always a desirable characteristic.

I have a 3.2 in my 74 and have run it with and without the rear sway bar only to find it handles so much better without.

Joe

So am I correct in assuming that the rear bars were added as the 911 took on more weight and her arse got wider??

The rear sway was standard on the early 911S from 67-0n IIRC. Optional on Ts. You will need the trailing arms that have the ball mount to add the rear sway.

My 911E came delivered with hydropneumatic struts and no bars. I converted them to hold inserts, used T torsion bars and added factory sway bars to both ends. Overall for street use I like the bars on both ends.

When I was autox-ing it depended on the course as to wheather I left the rear sway bar as is or un-hooked one end.

Good luck,
David Duffield