Help me decide the suspension. 1971 with 3.2

Alan.UK · 11-19-2004, 06:58 AM

Hi all,

I hoping to get some advice on which suspension torsion and sway/anti roll bar sizes to go with.

Funds are relatively tight(ish), so if I can use any parts I have or use parts from other later Porsches, that may help.

The car is a 1971 911 and has front and rear sway bars from the factory. What is the best sizes to go for. The car will be mainly be a fast road car, but I would like to take it for some track days.

A little back ground. 1971 911T with Short Stroke 3.2, running early exhaust, 46 PMOs, early 915 box, SC front suspension, 3.2 front and rear brakes, rear banana arms have the ball socket attachment for the anti-roll bar.

So far my first thoughts are

21 front 26 (from a turbo) rear
Not sure what sizes for the anti roll bars, can I buy just an upgraded front and rear bars on their own ?

Thanks in advance for any advice

Alan.UK

addictionMS · addictionMS's Garage

I don't know the sizes off the top of my head, but I have a 1970 with 3.2/915 running a stock Carrera (1985) suspension, with Bilstein HD shocks, and stock Carrera sway bars, and it is stiff, I mean really stiff. fun to drive, but if you want to drink a coffee better be on a smooth road.

I am sure someone will know what came in a Carrera or a search will tell you it is in the achives for sure.

This combo is usually pretty easy to find.

BTW the ball socket attachment is a bear to get attached, so I woudl consider looking at any after market bars that don't use it like SRP bars.

Should/Will be a very fun car!!

Jim

Chuck Moreland · 11-19-2004, 07:46 AM

If funds are tight I'd break the project into two phases and use the "inside out" approach.

Inside out basically means you upgrade the stuff that is deep "inside" the suspension first. eg. torsion bars and bushings. This is a labor intensive upgrade that includes R&R of the parts plus setting ride height, corner balance and alignment. But the labor is common to both parts so do them together and do it once.

The "outside" are items like sway bars and strut braces. These items can be done as stand alone projects when funds allow. They don't require repeating labor steps performed while doing the "inside" work.

That said, I'd go with 21/27 based on your description and intended use.

Todd Simpson · 11-19-2004, 08:39 AM

Agreed with Chuck on the budget approach, I've used stiff torsion bars and stock '71T sway bars for over 2 years on my dedicated track car and it was quick and stable.

My T bars are 22/28, probably a bit much for your use.

Alan.UK · 11-19-2004, 08:58 AM

Thanks for the quick responses.
It sounds like 21mm for the front is best choice, but
1)Will there be much difference between 26 and 27 for the rear, as I can get the 26mm much easier as they were standard in the Turbo (I think)
2) if I can get a complete rear suspension set up (with the anti roll bars) from a 3.2 would that be a better approach than running the ball socket arms with upgraded anti roll bars? I was led to believe the ball socket type anti roll bar was better
3) it sounds like I can leave the front anti roll bar in there for now, but if money was no object is this the best set up for me? if not what size should I be looking for, I think they come in 16 (original) 19 and 21mm.

Thanks for your advice, as I/we decide the best route I will be searching for these parts (just incase you have any for sale).

Thanks

Alan

randywebb · 11-19-2004, 09:40 AM

This is an interesting thread fro me as I have about the same combo and the PO put in hugely stiff T-bars that need to be softened. Mine is a '73 with a carbed 3.2L in it. I am going to lighten the rear some more (prob. take out 100 lbs. total from that end) and it is a street car.

I looked at the wts. rel. to the stock wts. - the 3.2L is about the same wt. as the stock engine once you lose all the FI and exhaust stuff on it. So that suggests the stock setup - or something close to it - as the soft end point for the range you want to try. If your 3.2L is heavier, then alter that.
I also discussed this with Bruce Anderson who also came up with 21/27.

You can try different Tbars if the cost and hassle (labor) permit. That's the real answer.

Be careful with the $$ no object questions! Some have put erp suspensions in the front of these cars, and 993 rear susps. in also. A step down is usually considered to be coilovers, but I don't see the benefit for a street car.

Alan.UK · 11-19-2004, 10:57 PM

Thanks for the advice...

21/27 it is.

I know a chap selling the rear suspension from a 3.2 so I may fit that as that way I get all the brakes as well. as well as the arms and anti roll bar. On my motor, the FI and old exhuast system, even the distributor as been removed so it's interesting to read Randy that the weights are similar.

With regards the front roll bar should I upgrade that whilst I am doing all this, or as Chuck says, is the 16mm one ok for now. I have seen a 22mm one on evil bay.... or is 22mm to much ?

Sorry to keep asking so many questions, but I hope to be doing all this over the Christmas vacation.... the car is going to the body shopnext week... now it's time to figure out how deep the valve pockets need to be cut, in the Max Moritz pistons so I can run my S cams.????

Cheers

Alan

Todd Simpson · 11-20-2004, 08:04 AM

Pass on that 22mm bar. Put fresh bushings on your stock bars and enjoy.

I got rid of my 16mm stock bars and went to used Weltmeisters this year. They knock and squeak, totally out of character with Chuck's slick bushings and the rest of the suspension upgrade. Performance upgrade seems minimal.

If I had to do it all over again, I would have kept the stock bars for another year or two and saved up for high end sway bars like Elephant or Smart Racing.