T-bar question for 3.6 conversion and backdated cars

[Joeaksa]

I have a 1985 911 that has been backdated and a 3.6 stuffed in the back. Love the car but you can tell when you drive it that it needs a bit of help in the way of torsion bars.

Right now the car has Bilsteins that are fairly new. Put HD's in one end and Sports in the other, forget which went where but liked the way they felt.

Also its got stock bushings in the suspension so thats also going to have to happen when we do the T-bars as they are showing their age.

What were the stock T-bars on this car? 19 or 20mm front and 24mm back?

Any suggestions for a mix like this? The 3.6 adds some weight to the mix, but then I took lots of weight off of both ends while removing the impact bumpers.

I do not track the puppy but like to drive as the car was intended and not in a straight line.

Thx,

Joe

[Bill Verburg]

Originally Posted by Joeaksa

I have a 1985 911 that has been backdated and a 3.6 stuffed in the back. Love the car but you can tell when you drive it that it needs a bit of help in the way of torsion bars.

Right now the car has Bilsteins that are fairly new. Put HD's in one end and Sports in the other, forget which went where but liked the way they felt.

Also its got stock bushings in the suspension so thats also going to have to happen when we do the T-bars as they are showing their age.

What were the stock T-bars on this car? 19 or 20mm front and 24mm back?

Any suggestions for a mix like this? The 3.6 adds some weight to the mix, but then I took lots of weight off of both ends while removing the impact bumpers.

I do not track the puppy but like to drive as the car was intended and not in a straight line.

Thx,

Joe

Joe,
stock US '85
f/ t -bar 18.8mm
sway 20mm

r/ t-bar24.1mm
r/ sway 18


for a street car I see no reason to change these, the 3.6 is not much heavier than the 3.2 it replaced, by all means update bushings if necessary, probably the ERP bronze are the way to go.

The best bang for the buck wrt handling is going to be wheels and tires, I'd shoot for 8 & 9 or 9.5 x17 or 18, try to keep the tire height short. 225/255 is about right for hi-perf street use

if you really want to spend some $ '86 Carrera used 22/21mm sways which can really help flatten the car in transients, as always I prefer adjustables but they are a lot more $.

A really good performance alignment and corner balance is worth it too.

[johnsjmc]

For a budget improvement I would refresh the rubber bushings front and back .I used Poly front and neatrix rear.Locate a pair of 26 mm torsion bars from a 930 for the rear and update the sways to the 22/21 set from the 86 Carreras. There is enough meat on the rear swaybar to allow you to drill a hole on the arm stiffening it further. I ran this combination on an SC with a 3.6 along with Bilsteins and it was very good for not much money.

[Joe Bob]

I went 22 and 28mm T bars, with Carrera sway bars front and rear......

[midnight911]

johnsjmc has a point but my supposedly budget bushing only improvement ended up being upgrade to 23mm front, 30mm rear torsion bars...

[Tyson Schmidt]

22mm front, and 28mm rear is a nice street combo that will still work with your shocks and struts.

The 22mm front and 21mm rear sways from a late model Carrera would also complement them nicely.

I think this is the perfect aggressive street set-up. Especially if it is at or below Euro ride height. (keeps you off the bump rubber and can potentially improve the ride if this is the case)

[Joe Bob]

The world is about to end....Tyson has agreed with moi.....

[Joeaksa]

Originally Posted by Joe Bob

The world is about to end....Tyson has agreed with moi.....

Now to get Ingo in the mix!

Thanks for the ideas gents.

Believe that things are about to progress on my project and its very good to see!

Joe

[Joe Bob]

Ingo is in the same boat if I recall.....don't think he upgraded the sway bars though....

[ToddM]

I'm running 21/29mm T-bars on my 3.6

Theres virtually no weight in a 911 front and you aren't braking in the corners if you know what you are doing, so I feel that 21mm in the front is perfect for any street 911.

T-bars first, do sways second. The basis of the suspension is in the T-bars and build up from there.

[arrivederci]

I'm planning 22/29 w/ tarret sways for my '72 w/ 3.6. I already have elephant PB bushings and monoballs...

[Bill Verburg]

And just what advantage do you guys perceive for a street car from spending all that $ for big bars, other than bagging rights that is

bushes I can see, sways I can see(especially adjust-ables) big t-bars on a street car, nope, just $ that will never be used

[Steve@Rennsport]

Originally Posted by Bill Verburg

And just what advantage do you guys perceive for a street car from spending all that $ for big bars, other than bagging rights that is

bushes I can see, sways I can see(especially adjust-ables) big t-bars on a street car, nope, just $ that will never be used

Hey Bill,

Naturally, everyone has their own opinion about what they like and road conditions can play a role here, but many feel that a 3.6-powered 911 has a lot of rear squat when the power is applied and a mild torsion bar upgrade really helps combat that. It goes without saying that shock valving must match the spring rates in use.

JMHO, but I've found that conservative T-bar upgrades have negligible effects on ride quality while taming the dynamics of these cars.

[Bill Verburg]

Originally Posted by Steve@Rennsport

Hey Bill,

Naturally, everyone has their own opinion about what they like and road conditions can play a role here, but many feel that a 3.6-powered 911 has a lot of rear squat when the power is applied and a mild torsion bar upgrade really helps combat that. It goes without saying that shock valving must match the spring rates in use.

JMHO, but I've found that conservative T-bar upgrades have negligible effects on ride quality while taming the dynamics of these cars.

JMO but that hasn't been my experiance, you can spend thousands but to what end? If you track the car, yes, idf you want to spend money , fine, but for street use, no way is any t-bar increase necessary

[gtc]

I have never understood the obsession with running significantly larger torsion bars with stock or only slightly larger sway bars. It was the lack of roll stiffness in my car that really bothered me, not so much the pitch or bounce.
Sometimes I think people go a little overboard when they hear the famous Colin Chapman quotation: "Any suspension- no matter how poorly designed- can be made to work reasonably well if you just stop it from moving."

[ToddM]

T-bars are one of the less expensive components, how are you spending "thousands" on T-bars?

But I agree some cars have FAR too large diameter T-bars per the application.

[gtc]

$6-700 on new t-bars, plus installation, plus corner balancing... i would think you could hit $1500 easily.

[johnsjmc]

That's why I said refresh bushing with cheap poly and neatrix and "used" rear 26 mm bars plus "used" 86 sways.I would then do a "tripod" corner balance. Throw in a wheel alignment. Less than $500 total" Big improvement on a budget. I agree there is no need for more on a street driven car, 3.6 or otherwise.

[Tyson Schmidt]

Originally Posted by johnsjmc

That's why I said refresh bushing with cheap poly and neatrix and "used" rear 26 mm bars plus "used" 86 sways.I would then do a "tripod" corner balance. Throw in a wheel alignment. Less than $500 total" Big improvement on a budget. I agree there is no need for more on a street driven car, 3.6 or otherwise.

Totally agree with this. It's the way I would set up a daily driver. Best bang for the buck.