Stock front torsion bar size 17.9mm?, do I have the wrong ones,how can I check? Options

[porschetub]

Car has very firm ride in the front,I have Bilstein inserts in Boge struts but the ride is really bone jarring to the point that I have disconnected the swaybar to try and soften it up a little which it did.
Previous to unhooking the swaybar I couldn't even bounce the front of the car with my own weight,needless to say the car isn't that nice to drive (IMG:style_emoticons/default/sad.gif) .
Is there an easy way to check the size,are they marked on the ends? I strongly suspect they are too larger diameter or not setup right (indexing ?) maybe,any helpful suggestions guys,thanks in advance.
PS front is only lowered a small amount.

[raynekat]

Might be wrong...but you likely need to pull one so you can measure it's cross section.
I don't believe torsion bar sizes are marked on the ends.

[ottox914]

Pull one and measure it. You can use a 17mm and 18mm wrench to measure with. 17 should not fit, 18 should fit loosely. You could also have the bushings for the control arms be frozen solid, and not allowing any motion of the suspension to occur. Had this problem at the back of my car. Shocks and springs were not the problem. Consider all possibilities and you'll be fine.

[porschetub]

Might be wrong...but you likely need to pull one so you can measure it's cross section.
I don't believe torsion bar sizes are marked on the ends.

Thanks was just hoping....... (IMG:style_emoticons/default/biggrin.gif)

[rhodyguy]

Stock lower control arm bushings?

[Tom_T]

IIRC they were originally stock only 16 mm front & 15 mm rear on both the /4 & -6, or I may have that Bass-ackwards.

FYI - My `73 were stock, Boge struts with classic Koni Sport inserts, lowered an inch & all front bushings replaced back in 1980-83 resto/rebuild, & it rode fine without any harshness nor bump steer.

So maybe the bushings noted above & proprer smaller sized sway bar with smooth yours out? (IMG:style_emoticons/default/confused24.gif)

Here are the back-in-the-day Road & Track spec for my 73 2.0, but it doesn't list the sway/anti-roll bar sizes....



Good Luck! (IMG:style_emoticons/default/beerchug.gif)
///////

[bdstone914]

Torsion bars are marked on the end. Stock 914 or 911 with an L or R. 914 are rust color and 911 are black. Sway away are marked with a 4 digit group that tell the diameter and type ( 911 or 914) The one pictured are 21mm. I bet that is what you have. The sway bar is not going to make the suspension that stiff.

[bdstone914]

Stock is 15mm stamped on one end and rear is 16mm.

[porschetub]

Torsion bars are marked on the end. Stock 914 or 911 with an L or R. 914 are rust color and 911 are black. Sway away are marked with a 4 digit group that tell the diameter and type ( 911 or 914) The one pictured are 21mm. I bet that is what you have. The sway bar is not going to make the suspension that stiff.

Thanks Bruce ,great info,realized the swaybar wouldn't make it stiff,but disconnecting it give me some compliance (IMG:style_emoticons/default/dry.gif) .
Bushing were replaced when the front end was upgraded to 5 stud and Brembo 4 pot brakes....according to the PO,I don't distrust him much ,and can see he must forget stuff afterall it was around 1997 when he did the work,I got a great deal on this car.....enough said.
Thanks Tom,will pull it to bits and see ,as you do (IMG:style_emoticons/default/av-943.gif) .

[McMark]

How low is your car? You may be riding on the bump stops. That's a shitty ride and the fix is free.

[rhodyguy]

Release A upper cartridge nut and see if the control arm pivots freely. The relacement bushings could be binding. Are there zerk fittings?

[Dave_Darling]

Stock is 15mm stamped on one end and rear is 16mm.

Not the torsion bars! Remember that the 914 doesn't have rear torsion bars, it uses coil springs on the rear! The fronts would be 17.9mm, as mentioned.

The sway bars are the dimensions stated above; 15mm diameter for the front bar and 16mm diameter for the rear bar.

--DD

[porschetub]

Thanks to all, Dave,my research indicated 17.9 also,my swaybar is 15mm also,rear is yellow Bilsteins with 100lb spring...that parts great
Mark my car is lowered around 19mm in the front,can't go lower due to road conditions,car sits slightly lower in the front than rear,rear spring set to 5th notch on shock body.
Kevin strut moves up and down easily ,checked that when last on my friends hoist,did the ride height setting at same time,no grease nipples (zerk fitting) ,do you suggest I should do that,thought not as they appear to be rubber bushes?,would expect these for composite bushes.
I did a basic shadetree wheel alignment yesterday and test drove,ride has improved,certainly steering better also.
Will start pulling apart today and see what I have,will report back (IMG:style_emoticons/default/beer.gif) .

[rhodyguy]

Not the compression of strut itself but the control arm thru its range of motion. Other than stock rubber bushings on the control arm?

[porschetub]

Thanks to all, Dave,my research indicated 17.9 also,my swaybar is 15mm also,rear is yellow Bilsteins with 100lb spring...that parts great
Mark my car is lowered around 19mm in the front,can't go lower due to road conditions,car sits slightly lower in the front than rear,rear spring set to 5th notch on shock body.
Kevin strut moves up and down easily ,checked that when last on my friends hoist,did the ride height setting at same time,no grease nipples (zerk fitting) ,do you suggest I should do that,thought not as they appear to be rubber bushes?,would expect these for composite bushes.
I did a basic shadetree wheel alignment yesterday and test drove,ride has improved,certainly steering better also.
Will start pulling apart today and see what I have,will report back (IMG:style_emoticons/default/beer.gif) .