early85944

I take it very easy in first and second gear

jester911

Yeah the 915 won't stand up to much over 300 hp. You probably should come up with a solution for your tranny first and build the car around it. It sounds like rear ride height should be down on the priority list for that car IMHO.

early85944

I can live with the tranny for a while, I just want the rear end to not look like it is squatting

Steve Weiner-Rennsport Systems

If you install a properly matched set of torsion bars and the appropriate shocks, the squatting problem will be aleviated.

911S3.6

You are having tunnel vision here by only focusing on one piece of the puzzle. The thing that makes Porsches so great is they are an integral unit- engine, brakes, suspension etc all in unison and cohesive.
When you change one element, like putting in a bigger motor, you create an imbalance with the other parts. Suspension especially is determined by hp, tire size, car weight, brakes, street/ or track, etc. only someone with a lot of experience can discern. What some dip**** tells you on a forum board is bitchin might just make your car into a hooptie.
hope this helps,

Nick

Amber Gramps

Here is a total novice question for Steve: Will shocks alone solve the squats? My back end must drop 2-3 inches upon hard exceleration. I have figured out that my shocks are boge now with almost 69,000 miles on them. Will the shocks at least slow the squat, or am I going to have to replace the T-bars too? I know you are the best suspention guy on the board and I'm not going racing, just looking to restore the car to it's original glory. What do you think? It's T-bars too isn't it?

Steve Weiner-Rennsport Systems

True wisdom from Nick,.....suspension systems are integrated, matched components carefully chosen to work correctly and achieve the desired objectives. Its not an "al la carte" process,....


Doug:

Shocks do not control the "squats",....thats the role of the springs (torsion bars). The role of the shocks (properly called dampers) is to control spring oscillations as well as the RATE of lateral, longitudinal, and diagonal weight transfer.

Springs, dampers, and anti-roll bars (swaybars) all have different but complementary roles in the suspension system and in some cases, those can overlap a bit.

Your Boge's are pretty well done by now and are prime candidates for replacement. If you wish to reduce the squat, you should plan on replacing the torsion bars based on how you use the car and a matched set of shocks. The ride quality is not compromised provided that the choice of T-bars is correct.

jester911

+1 Nick and Steve^^^

early85944

Guys I am no novice here. I used to work at a Porsche shop but unfortunatly it was mainly on later model cars pre equiped with coilovers. I am not building a hooptie. I have had the turbo motor in the car for three years now with no problems, and yes I did all of the work myself. If I had the cash yes I would have a G50 box but I don't. Unfortunately I have to go after the problem peicemeal as many of us do, due to cash flow.

jester911

If I were you I would find out what size the tbars are and depending on the size go bigger. They will be cheaper than trying to install coilovers and will be more sound. You will want to look at front and rear at the same time as you don't want to have spring rates out of whack front to back.
Also look at the spring plate bushings at the same time. Make sure they are up to snuff.

911S3.6

No insult or denigration intended
I put a 3.6 in my 911S when the 2.7 blew. It was incredible from the first drive. But, then i saw pics of it on the track, and how overwhelmed the suspension was from the power output. ( obviously i could feel the twist and squat in the body/suspension as well) A suspension upgrade balanced it back out. Now the car was faster and handled with aplomb. But guess what? The 2 piston S-calipers just weren't up for the task.
So, I had a custom fabricated set of 930 calipers/brembo disks/ 23mm brake M.C. made by Rennsport Systems and installed that. Whew! Now it was all back together, integrated. But, the narrow body restricted wheel/tire size, and then there was the need for aerodynamics, and what about keeping that 915 trans together with all that hp/torque?
I have watched many a car be piece mealed together only to end up with something worse. I'm not a rich man so i needed to be sure to do it right the first time. The only way to do it was to have the guidance and expertise of someone who has done it a bunch of times, has raced IMSA/TRANS-AM in these cars...and has the knowledge base to extrapolate all the info and put it to practice.
Steve Weiner did this with and for me and the car is staggering.
P.S. I still run torsion bars, stiff bars, and the difference in ride compliance and adaptability to different road situations/track is in the JRZ shocks.

Hope this helps, no insults intended, just trying to share some experience here.

Nick

early85944

Nick,
I was not insulted sorry if I came off rash. I will investigate the t-bars issue and prehaps go with some stiffer valved bilsteins to correct the problem

Elephant Chuck

I few things to consider in the add-coil-helper vs reindexed torsion bar choice:

1) cost of RSR shocks, helper coil springs, hardware kit, and custom valving handily exceeds the cost of new adjustable spring plates
2) adding coil helpers without re-indexing the existing tbars can only raise the ride height, never lower it
3) you need to realign and corner balance the car after the work, no matter which option you choose due to changed ride height
4) your '76 spring plate bushings need replacing either way, to fix this you are removing your spring plates

As usual, Steve is offering excellent advice. The task of setting up ride height, corner balancing, re-indexing, and even replacing torsion bars has been greatly simplified by the new spring plates Steve is talking about. And you would install new spring plate bushings at the same time.

Going the torsion bar route will be less expensive and will address all the issues (bushings too). To do this right, there really isn't any difference labor wise.