ttAmerica RoadsterAWD

Taking some notes here in case others might want to pursue this project, particularly if an owner has a C4. So, so far here are some hiccups with my project:

My car is a Frankensteined hybrid of 964/965/993C4S/993tt Thank God I purchased it already done, and the original owner took the financial hit for this conversion. In swapping hardware from the old upright (iron 965 upright) to the new aluminum EVO upright I came across three problems thus far:

1. The four bolts that retain the bracket just behind the hub were too short for the EVO upright. I had to go to NAPA and get eight (four on each side) 45mm long bolts (originals are only about 20mm). Seems the aluminum EVO upright has its threads start deeper than the original 965 upright which are threaded right from the surface.

2. The ABS sensor on my 965 upright is 90 degrees different than the mounting place on the EVO. I now need to order two ABS sensors for a "993".

3. If you don't have 4WD, you won't have this problem: I discovered my original 965 upright, on the back side (facing the center of the car) has a circumferential cut-out at the very end of the lip (surrounds the bearing). This is so the rubber boot can be mounted onto a tin ring (its about 1/2inch wide). When mounted to the tin ring, it then overlaps this cutout all around the circumference and provides an element of barrier against debris going into this space. The EVO upright has no such cut-out. If you don't have 4WD you will just place a cap on the back side and your done.

Now, about the dampers (shocks). Well, turns out I made a great (good) mistake 6 years ago when I ordered JIC/Cross for a 993tt (I was under the impression I had a 993tt upright), but as described above, I actually have a 965 upright and so the bottom bolt was actually a loose fit. Now, I have a perfect shock that mounts perfectly onto the evo upright. I don't have to drill the hole on the shock to 14mm cause its already like that. This was nice!! However, there may be the distinct possibility that JIC/Cross purposefully makes the bottom hole 14mm to fit both the 964 and 993??? Maybe not. I think I just ordered the wrong part back then.

Well, I'll need to wait until I get some boots and ABS sensors ordered (tomorrow). Will post more info as I go along. If any of you guys have any questions let me know.

Jaime

Bill Verburg

all 964 struts(including turbo) used 2x 12mm bolts to hold the uprights to the strut. If the lower bolt is sized for M14x1.5x55 then that is a 993 part(unless JIC ships them all that way)

did you have any issues w/ the tie rods?

ttAmerica RoadsterAWD

Hi Bill. I'm going to tackle the tie rods today. Will let you know soon.

Bill, have you ever done evo uprights on a 964 C4? If so, how did you correct for problem # 3 above?

Anybody welcomed to chime in

DAVISRILEY

I think I am the reason bill is asking about tie-rods. I have 993 plain jane uprights, and ran into all of the same issues that you have run into. I ended up with the 993 sensors also. The problem I ran into with the tie-rods was the stock rubber dampened 993 tie rods were about 1/2 inch too long, iirc. I ended up having a machine shop extend the threads, and then trimming them a bit. After that was done, it worked fine. I don't know that you will have that issue with the evo's though. Good luck. As far as #3, what I did was cut the outer cv clamp off, tap that ring off and cut it off the axle, and replace the clamp. I can't see how that would cause a problem, and 4 track days and 5000 miles later, no leaks, no problems.

Bill Verburg

No experiece w/ 964/993 awd here. mine is 992 2wd and all the others I've seen have been 964Cup or other 2wd 964 versions

ttAmerica RoadsterAWD

Well, I got the tie-rods in ok, I just screwed it into the steering rack. I was surprised to see a "fork". I had been memorizing previous installations and none appeared to have this fork, must be a 964/5 thing.

Still waiting for rubber boots/ ABS sensors/grease to pack (using Swepco 101).

DAVISRILEY, thank you for your info. I hope i don't have any more snags

Bill Verburg

Yes, the 964 inner is a fork like arrangement, so you just used a 993RS outer and inner between the uprights and rank? No issues like DR had ?

DAVISRILEY

If you need any info, shoot me a pm. Good luck.

ttAmerica RoadsterAWD

Hi Bill, I just screwed in the entire evo tie rod without issue. I compared the original tie rod (entire assembly) to the evo tie rod and they are about the same size. I screwed the evo tie rod into the steering rack about half ways so I know I'll have some room to go in or out. But, I've just learned I need to have 4-5mm space between the square locking nut and the tie rod. Guess this is the limits of travel for the steering?

Well, maybe its not a good thing that they are the same size. Maybe the evo needs to be a little shorter to account for the shorter reach to the short evo connection, relative to the longer stock connection.

Well, the fat lady hasn't begun to sing, so I'll keep you informed. The proof would be after entire assembly is in and alignment is feasible.

Jaime

PS. Of note: There are three types of tie rods that would fit. There is an RS tie rod which has hard rubber damper, a __________ which has a soft rubber damper and the EVO which has no rubber at all. It has a spherical metal bearing and that's it. From what i've been reading, if you want a direct, mechanical feel and response, go with the EVO tie rod end, which is what i'm doing.

Bill Verburg

that's great to hear, I'm still trying to figure out what the issue was w/ DR's car that required mods to the (I assume) inner tierods.

ttAmerica RoadsterAWD

Hi Bill, I think you read my original post. I've amended it. If the evo tie rod and the original tie rod are the same length then maybe I'm going to have an issue too?? Since the evo upright has a shorter arm then it follows that the tie rod should also have a shorter length. Right??

We'll see

DAVISRILEY

Iirc the tie-rod lengths overall were about the same between the 993 and the 964. Near as I can figure, the difference that i ran into was the orientation of the steering arm off of the hub is a bit farther in on the 993 versus the 964. What I could not figure out was what the difference between the 964 and tub is.

ttAmerica RoadsterAWD

Oh, you changed out your iron 964 upright for an aluminum, standard 993 upright. Hmmm, you would think the tie rod lengths would be the same, right? So, the steering arm on the 993 upright was a bit further *in*? This would leave you with a too long of a tie rod....is this what happened??

Bill Verburg

w/ the 993 stuff the outer is really the only special part, discounting spherical bearing inners that are some times used.

DAVISRILEY

You would think. I really haven't figured out the difference, and have confered with people much smarter than I. The control arms are the same, the upper strut mounts in the same location, etc. The only thing that we have been able to come up is that the control arm mounts in a slightly more outboard position on the 993 tub.