1965 911 Rear Height adjust, Need advice!

Gringo · Gringo's Garage

I have a 1965 Porsche 911 and need to raise the rear suspension. In all the tech books I have it says to take to a specialist, but where I live there is no one near that can do it. Does anyone have easy to understand instructions on how to do this or a link to a good web page? I am thinking the rear shocks are toast anyway, will putting in new shocks raise it significantly? Also do I need to be brand specific, it has the orange Koni shocks in it now.
Thanks for any and all help!!!

ZOA NOM · ZOA NOM's Garage

This is definitely not a job that requires a specialist. Spend some time searching this forum for plenty of information. New shocks will definitely raise your ride height a little, but the suspension bushings and torsion bar settings will have to be addressed to really refresh the rear end.

Zeke · 07-12-2008, 10:10 AM

Depends on the shocks you purchase. Some are gas charged and will raise the back a small amount. Normal shocks (not saying gas charged isn't normal) will not. You will need to pull out and reindex the rear torsion bars. On a car that old, this can be a tough job, so understanding not only what it entails, but what can become a hurdle is necessary. In the past, we have had folks hare on this BBS had their car between phone poles pulling on the ends of the bars with come alongs. This is not a good method regardless.

Patience and a lot of penetrating oil is a good place to start.

Also, and I wish I had this committed to memory, the rear t-bars have like 26 splines on one end and 25 on the other. This allows for micro adjustments. It's not like pulling out the bar and rotating one spline and reinstalling. Most often you will be several splines over from the original setting and a few back from the original on the other end.

If someone would like to link Fitzpatrick's and Ferch's calculation pages, that would be helpful, but please find that info about the splines so I can bookmark it. This comes up all the time.

Zeke · 07-13-2008, 02:13 PM

ttt, please for that useful info

fbarrett · fbarrett's Garage

Gringo:

PCA's Upfixin der Porsche, Vol. 1, contains simple step-by-step instructions. I used them in about 1970 to lower my 912 and later to lower my wife's 911E. I don't know if the book is still available, but check www.pca.org.

Frank

ossiblue · 07:25 AM

If my memory is correct, there are 40 splines on the inner end and 44 on the outer end.

edit: Thanks Jon, for the correction.

shbop · 07:26 PM

My factory manual shows Inner end 40 spl, and the outer end 44 spl. From the book: " If the torsion bar is reset by one spline at its inner end, a 9 degree change is effected. If the radius arm is "reset" by one spline at the outer end of the torsion bar, a change of 8 degrees 10' is effected. This results in the smallest change of 50' in the radius arm adjustment." Hope this helps.