torsion bars for my 73 targa?

[sundevil64]

I have a 73 targa with a 3.2l motor, koni adjustable struts in the front and bilstein hd's in the rear. I am most likely going to install some polybronze bushings all the way around and I need a rear sway bar.

I was going to run a set of turbo Tb's(I already have a set laying around) on the rear and 21 or 22mm Tb's in the front. I can run a set of adjustable koni's in the rear of custom valve shocks.

This car will see spirited road driving and possibly a DE.

Thoughts or suggestions

I do have some alum rear control arms that I could put on. What is involved with that?

Currently there are 16" Fuchs but I plan on running 15" 6/8's.

[rkeele]

yes install alum. swing arms they will bolt right on to a 73 much lighter, if you install larger front torsion bars you'll need rear ones they are more important anyway.

[Flieger]

21 or 22 is going to make the car very front stiff. I would not use 22mm fronts without at least 29mm in the rear. Turbo 19/26 should be a good place to start.

[HarryD]

I put 21/26 t-bars in my 1973 to reduce squat and a tire rub. The ride is still very acceptable on the street and is noticeably better at Autocross.

[targa44]

John,

I just bumped up to 22/28 from 21/27 and I'm okay with the 'firm' ride. It's not too harsh.

I also switched to alum trailing arms this year - you'll probably need the hubs that go along with it. I think the bearings, etc are larger that leads to a beefier hub. Also may need the plates for the e-brake. If you have an early '73, you may have to drop the engine to get the front bolts out - I think they changed mid-year with the notch in the tb tube to allow easier change/repairs. (I, of course, have an early). And, you'll need slightly longer eccentrics for the thicker alum arm. If yours is an early, Wevo has a special replacement bolt that allows changes/bushing replacement without dropping the engine in the future.

good luck,

kj

[safe]

I would stay with 19 if you have 26 in the rear. I have 21/27 and would not recommend anything with more front bias.

[sundevil64]

Thanks guys.

From a cost stand point I plan on staying with the turbo tb's in the rear. I may have the turbo tb's for the fronts. I will have to look. IIRC they should be 18.8mm. I would guess that should be close enough.

Next would be is it worth it to switch to alum trailing arms. I have a complete set that I pulled from an 84 targa, parking brakes and all. I don't know if I have an early or late 73. Are there any modifications that need to happen with the axles? The trailing arms I have have the stub axle in them. I guess another incentive is I will not need to buy a sway bar as I have a couple rear sway bars from later cars and currently my 73 doesn't have one.

[tctnd]

I have 21's & 26's in my 2190 lb hotrod and find the ride perfectly acceptable and the handling great. It is not good on very poor road surfaces but I try to avoid those. While you are in there, be sure to reinforce the rear sway bar mounts to save yourself headaches down the road.
regards,
Phil

[sundevil64]

tctnd,

I will do. It is on the list. I think I will do the rear suspension first and the front after, to keep the down time minimal.

[HarryD]

Originally Posted by sundevil64

tctnd,

I will do. It is on the list. I think I will do the rear suspension first and the front after, to keep the down time minimal.

Each time you mess with your suspension, you will need to repeat the alignment and corner balance. This is a significant cost. As recommended to me by Steve Weiner (Rennsport Systems), to save your money, do all the changes and then tune your suspension once. It will take about a day or two to do the total job.

FWIW, I had Jeff at Rothsport Road and Race do the suspension tuning after I installed the parts. I asked him about setting the ride height prior to having him align and corner balance. He told me if I wanted to practice doing this job, it was fine but it was likely he would still need to make adjustments and there would be no cost savings. I let him do all of the adjustments.

[Dantilla]

I used 23mm front and 31mm rears in my 3.2 powered '73 coupe.
To do over, I'd do..... exactly the same!

The car was primarily an Autocrosser. Some may find it a bit stiff for a daily driver, but I love it that way.

[safe]

Originally Posted by harryd

to save your money, do all the changes then and tune your suspension once.

+1