Strut / Damper Identification Help

[IanHighfield]

I am hoping the accumulated wisdom of this forum can help me identify a set of 964 (RS / Cup ?) struts and dampers.

The fronts are green Bilstein with the number 96434351070 and 964350970. My local OCP could not identify the part description on PET but could price them at over £400 each - they do not have access to the MotorSport system.

The front dampers have the following numbers on them (probably Bilstein numbers) 49778 2205 670 and 50431 2205 670

The rear dampers are dated 05 91 and have part number 96432350370

I have the front black springs and rear 'blue' H&R 100 which I need to investigate further.

I believe they may be 964 Carrera Cup dampers, but hope someone can help.

I had hoped they might be 964RS suspension parts, but the short top thread gives them away as the 964RS has the longer 72mm thread to go through the Monoball. Cup monoballs are different but are the tops of Cup Bilsteins the shorter thread.

I am sure they would be way to stiff for a road car (?) but could be revalved to softer settings, or alternatively I will thoroughly clean and make them available to others if no good to me.

Ian

 

[chfs911]

964 343510 70 Right front

964 343 509 70 Left front

964 323 503 70 rear

Cup parts 1992 catalogue

 

[IanHighfield]

Many thanks for a speedy response.

Is there a way I could get a hold of more references by part - is the Catalogue on line or PDF etc.

This only confirms that the parts are not suitable for road use - or are they ??? I need to unwrap and review the springs.

Do these use a conventional monoball like the one from Tech9 or Rennline, whereas I know the RS used the deeper threads and the different monoball.

I will get it all cleaned and photographed.

The parts were removed from a 964RS Lightweight that had been prepared to Cup Spec and that accounts for the correct Cup Suspension.

Any clues on likely value and could I realistically expect to be able to swap it / exchange it against correct RS setup ?

Ian

 

[964RS_DAB]

Ian

I have sent you a copy of a quotation that lists all of the 64RS OEM part numbers. Ignore the prices, they will be out of date now.
cheers
David

 

[ChrisW]

Ian, I have Cup dampers on the front and standard N-GT dampers on the back.

I am not discerning enough to know why --- but I do know that 9M will have driven their specification.

The Cup front dampers were much more expensive than the standard RS ....

I hope this helps.

Incidentally Charles, where do you find all this information ?

 

[chfs911]

In my head Chris! Hence quick response.

 

[IanHighfield]

Charles - excellent memory recollection powers. Seriously, is there anywhere that the Parts Catalogue can be sourced from out of interest.

David - got the list thanks.

Ian

 

[IanHighfield]

A few more figures to wrestle with.

The Porsche part numbers are correct then for Bilstein Strut bodies, but the inserts (dampers) are separate and need to be assembled in to the bodies. The reference numbers on the inserts are probably Bilstein and are 49778 2205 670 and 50431 2205 670 - any clues, as they are the correct 40mm width for the Cup Dampers, but a clean up may expose more markings.

I also have two sets of springs with them. One set is a brownish red and marked H&R 120. The other is blue and marked H&R 100. Again, and clues as I have no idea if Porsche used H&R springs or whether these were fitted later, but they were the combo run on the 964RS Lightweight that had been 'Cup' converted.

Chris - do you have Cup dampers and springs on the front, or just the dampers ? If you have the dampers then they are the 40mm width items and have the shorter top thread, so assume you have the Cup Monoball ?

Does anyone have a good chart of the various spring and damper rates ?

Ian

 

[chfs911]

http://carreracupusa.org/street/S-Suspension/S-Suspension.htm

 

[chfs911]

http://www.carreracupusa.org/964-parts/964%20cup%20parts%20list.pdf

 

[IanHighfield]

Thank you Charles, that is a great site.

So I have the Cup Suspension albeit with as yet to be identified H&R springs.

Decision is whether to keep it or refurb and then get correct RS suspension (David - I got you r email )

Ian

 

[IanHighfield]

And here are the first photos of the Cup Suspension

I have thus far cleaned these parts and haven't identified if they are front or rear, except the strut body of course

I have the front inserts and the rear dampers and the H&R 100 / 120 springs and a few other fixings to clean and photograph next.

The dampers will be taken to Bilstein as they are close to my workplace for testing.

And this came from a post over on the Rennlist Forum :-

- I think H&R list their springs in N/mm rather than lbs./inch,

- 100 N/mm = 570 lbs.
- 120 N/mm = 684 lbs.

- From the chart included the rears appear to be what is known as H&R 964 Supercup springs:

- Although the chart looks nice it has some flaws, Porsche never gave data on 964 RS springs (they do for a 993RS BTW). If I'm not mistaken the data mentioned for the 964 RS stems from this forum and is nothing more than a guess made by a contributor.

Any views on those rates and how close are those to original - did original have progressive springs - I know I have a lot to learn here ?

Ian

 

[IanHighfield]

Spoke to a very helpful chap at Bilstein today and I will take my dampers to them on Monday where they will put them on a shock dyno and provide me with various graphs and reports - £10 per shock. They have the original specs. etc so should be interesting to see how they perform.

They can revalve to any spec. for £80 + VAT each.

They also mentioned that Porsche originally used H&R springs so my springs may in fact be original ? They offered to take them over the road to Eibach and have the springs tested and reported on as well - great service.

Will report back next week.

Ian

 

[chfs911]

You'd better get a Brian James too while your at it! ;O)

Not fun on the road over 40 mph.

 

[IanHighfield]

Charles

Original purchase was thought to be RS setup but subsequent inspection showed it to be Cup.

Thought I would have them checked over by Bilstein so if I decide not to keep them, then at least I can sell them on knowing them to be good.

I am happy to keep some parts on the shelf for that 'one day in the future' RS/Cup themed car I would like to build. I enjoy research, parts finding and refurbishing and then assembly, so happy with the bits I have so far - now if I could come across some 993RS / Evo uprights and tie rods

Ian

 

[IanHighfield]

And a few pictures of the cleaned up Cup rear dampers and 'Miscellaneous to be identified' H&R springs before they go on the 'shock dyno' tomorrow :-

Ian