I was thinking of buying a set of these rear mounts - http://www.rennline.com/Rennline-Rea...nfo/SB69%2E74/ and had a couple of questions I wondered if any of you guys could help with?

First up is that on the Rennline web site it states "RS style spring hats required" and I was wondering if this is a part I can source from Porsche or elsewhere? Has anybody bought these and fitted them? Why is a RS style spring hat required?

I've got Bilstien B6 shocks and H&R sport springs.
Many thanks in anticipation,

Ossie

 

The Rennline rear top mounts are nice pieces, I have them on mine


for Bilstein HD/B6 you'll want 12mm bushes, the spring mounts you have should be fine

 

Great Bill! Thanks very much. Do you think the note "RS style spring hats required" only refers to fitting the mounts with standard/original shocks & springs?

 

probably the oe top mount is different for sure

 

Which springs are you planning to use?

 

I've got a set of H&R springs

 

What they mean by "hat" most people call a "spring perch". To use the RS style bearing mounts, you need the spring perch that goes between the spring and the mount as used on the Euro RS

I have a couple if you need them PM me.

 

Thank you, that is very kind of you to offer. However, I'm in Glasgow, Scotland and I was hoping to get my suspension fitted next week...

Do you think these would be available from an official Porsche centre? Any ideas of a part number?

Do you think Bill is mistaken in thinking that with the Bilstein B6's the spring perch will be fine with the Rennline mounts?

Thanks again

 

Yes they are a dealer part # 993.333.523.80 "concave washer" in parts list.

Now. Big NOW, I am going by what Rennline says that they work. I have not done this myself as I use 60 mm race springs. Can you check the ID of the springs you have and I will check that against the RS parts to make sure they work. The part is shaped like an upside down "Top Hat", the cylindrical top plunges into the spring and the brim catches the spring top. The cylinder OD has to be correct diameter for the spring ID.

 

You can see the parts here where Jackal had to have a custom perch made to work with the 60 mm springs on a Bilstein kit

http://www.jackals-forge.com/lotus/9...stopmounts.htm

It is part 8 in this diagram, thanks to Jackal:

 

Also, the RS top bearing won't work with stock C2 upper spring perch mounts.

 

Read posts 77 - 81 in this thread -> https://rennlist.com/forums/993-foru...ml#post9614905

Compare RS vs. base in the photos above.

You'll want to confirm the i.d. of the springs you're planning to use match the spring perch / hat dimensions & that the threaded portion of the shock itself is long enough to reach through the top mount.

 

Thanks.

The rear springs I have are marked in the following order -

H&R F/E, Porsche 993, KBA 90420, 29953 HA (R)

 

I thought the Rennline mounts were different to the RS?

I had a look at Jackals post, thanks. So, you recon I would run in to the same issues as him? Jackal fitted PSS10 with RS mounts and as you know I'm looking as B6, H&R springs with Rennline mounts.

 

Rennline appears to have copied the RS mount, if Rennline say their mount will work with stock shocks presumably then the top stud is long enough.

When you say "H&R springs", I am assuming you are using a stock diameter spring kit, not race springs like the Bilstein PSS kits come with.

H&R also makes a full suite of 60 mm race springs and I want to make sure that is not what you mean.

The PSS9/10 kits come with the smaller 60 mm diameter springs, that is why Jackal had the issue with perch diameter and could not use the stock RS part.

If RS springs are the same internal diameter as C2, then you are good to go with the RS perch.