I am in the process of installing (already purchased) spherical bearings on my 914-6. The "six" will be driven mostly on the street (80%) and at the track (20%). Is the drive on the street going to be unbearable? Am I going to have to worry about wheel bearings every 2,000 miles? The car shaking apart? I live in Southern California where the streets are kept relatively well maintained.
More details on my suspension;
930 Complete Front Suspension incl. Delrin Bushings.
930 Brakes & Rotors All-Around.
Front Koni Racing Shocks & Struts w/17mm Raised Spind.
1-Degree Decambered.
Front 23mm "Charlie Swaybar".
Front 8x15 Forged Fuchs
Rear Koni Racing Shocks, Dual Adjustable (3012)
200 Lbs Springs
Stock 914-6 Rear Swaybar
Rear 9x15 Forged Fuchs

Should I abandon the spherical bearing idea completely or simply enjoy the car and put up with the rough ride? This is NOT my daily driver, just a real FUN car!

Thanks!
<img src="graemlins/jumper.gif" border="0" alt="[jumper]" />

 

There is no application for spherical bearings on the trailing arms, i.e., the trailing arms don't lend themselves to it. Spherical bearings at the top of the front struts are highly over rated. Neither front nor rear bearings in a race/autox car have any bearing on ride comfort.
Phil

 

I had rear monobals installed in the trailing arm pivots on my 914/6 GT which had almost the identical set up to yours down to the Fuchs 8 and 9 inch wheels. I had 250 pound rear springs. The ride is not so bad as you would think and you will like the way the monobals facilitate alignment in the rear.

 

Cupcar,
Why would anyone want to install monobals in the trailing arm pivots? By pivot I assume you mean the inner trailing arm mounting (the ear). Rear camber and tow are adjusted by shims and lateral movement of the arm outboard bearing mounts. I don't understand what the justification could be for installing monobals in the suspension consoles.It's not like you are going to readjust the rear alignment every track day and certainly not during an event. Perhaps I am missing something here. If I am,I apologize.
Phil

 

The problem I had was that the inner trailing arm mounting nuts would come loose during track use on slicks and Delrin bushings, unless locktite was used. I also had trouble with the alignment drifting around because the outer mount (where the shims go) moved, despite careful torquing of the 3 bolts.

The other issue after seeing the above happen and beat the inner mounting holes oval, was that I wanted a stronger set up all around so I didn't kill myself. The design looked "on the edge" to me for what I was doing (or at least trying to do).

The solution was replating and stiffening the inner and outer mounts with plates and gussets ala factory GT but more extensively. Cups with circlips to retain a monobal were welded into the mounts and a new larger diameter CrMo axel that fit in the monobal was fabricated to replace the factory axel in the trailing arm. The trailing arms were plated on the top, bottom and inner surface. The 3 factory mounting bolts for the outer mount were drilled and replaced with 9/16" SPS aircraft bolts and torqued to a higher torque. This was done in the late 1980's for me by Don Araki who also did Wayne Baker's IMSA GTU winning 914.

After this the rear suspension was completely reliable, and I had peace of mind. BTW I did change the rear toe in at the track from time to time and this was much easier since I didn't have to bend the rear inner mounting ear to do it.

 

Cupcar,
Damn! Those mods. undoubtably cost more than most 914 cars. <img src="graemlins/icon107.gif" border="0" alt="[icon107]" />

Phil

 

Alan Johnson in Grand Junction Colorado does a great job on this. You just send him your trailing arms, he will do the mods and send them back, cost is around 625$ for it all.(Not affiliated etc...just respect his work!) Very nice improvement on a track car and seems fine for street use also...of course I am biased since my 993 has monoballs all the way around in addition to heim jointed rear suspensin multilinks! Another great modification to do while you are there is to weld 2 or 3 addition tubes horizontally and vertically into the inside of the trailing arms, like the one that is already there for the parking brake cable. Makes a internal stiffening roll cage for the arm and is much lighter than the boxing of the arms. I have used this on my 914-6 race car and run 13 inch wide slicks, no probs. The other thing you want to do while you are there is to replace the stock rear wheel bearings with the ones from the Audi 5000, bigger bearings, stronger piece, affodable and a direct fit... Hope that helps!

 

Again, thanks guys for taking the time to respond to my questions. Does anyone have close-up digital photos of the "heim" joint modification to the 914 rear-trailing arm that they can email me?

My email: ajserrano@msn.com <img src="graemlins/jumper.gif" border="0" alt="[jumper]" />

I am referring to an adjustable link connecting the outer pivot point (cup) of the rear 914 trailing arm to the "longitudinal" (chassis). This simple modification helps to maintain the "toe-in" adjustment while setting it and after. I was told a worthwhile modification.

I welcome all comments...

Armando

 

Glenn,

Regarding the Audi 5000 wheel-bearing swap. I am not completely clear if it is just the bearings we change or there are additional modifications that have to be made to the arms or the 914-6 drive flanges to accept these "bigger" bearings. You mentioned "stronger piece", you meant the bearings(?). You also said "a direct fit" which implies "no modifications required"...

I am almost ready to have my rear arms send out to the powder-coaters and this would be the time to do this bearing change if modifications to the arms are required (however small they may be).

Thanks again!

Armando <img src="graemlins/jumper.gif" border="0" alt="[jumper]" />

 

Armando, the 5000 bearing is indeed a direct fit. The actual bearings themselves are larger inside the 5000 bearing vs our 914 bearings and are much stronger. i will try to post a PN for you if I can find it later today. BTW I highly recommend doing the internal cross bracing inside the trailing arms while you are at it. Very easy to do for a good welder. You can even do this mod if you have already boxed them. We found this was very effective at reducing the twisting of the arm under heavy loads. Hope that is helpful.