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I am looking to upgrade the rear shocks on my car. Currently the car is setup with the stock stud/pin upper mount and rod end bottom mount. Most double adjustable shocks are rod end on both ends. I have been reading the rules and not sure if I can change the upper mount to a rod end style. The upper stud mount "receiver" on my car is bolted to the body and is refereed to as a "Guide support" in the factory manual. There is a rubber mount that goes inside this support.

Here is a picture of the upper mount.



Rule states:



The "stock system of attachment" is the sticking point for me.

Otherwise does any one know of a good double adjustable stud/pin mount shock? I think KONI has some options but I have not had a chance to give them a call.

Looks like your stock system is a vertical stud...

there are a lot of ways to make a vertical stud work quite well as a shock attachment.
Spherical bearings are the first thing I'd think of, but I'm sure others are more clever.



t

I already have ideas on how to do the spherical bearing upper mount, It is mainly the availability of double adjustable shocks that have a length of 12 inch (9 to 10 inch lower mount to top of body) with 5 to 6 inch stroke that are also stud/pin upper mount.

I know that TC Kline had KONI build some double adjustable shocks for the E30, E36, and E46 chassis but the body is a little too long and I would bottom it out which is my current problem.

I think it is time to start making more phone calls, if I get some free time....LOL

Ground Control makes a vertical stud mount configuration of the Advanced Design double adjustables.

Ron, I used a shock made for an Opel. I don't remember the model but it is a starting point. G

http://www.anzesuspension.com/build_options.cfm


Go to the bottom of the page, "racing chassis mount-adapters"

Adapter like this could take up some of the shock space, but looks like it would be easy to make or just buy from somebody that has made them.

The adapter mounts to the body just like the original shock, does that comply with the rules??

Very interesting thread.

By rule:

Shock absorbers MUST be installed in the STOCK LOCATION using the STOCK SYSTEM of attachment.

By Glossary:

System - An assembly of components with an identifiable primary function.

Does the ol Pickup Point/Pivot Axis rule come into play.

Glossary:

Pickup point (Suspension) - The location of attachment of a suspension component on the frame or structure of the car. Pickup point is also pefered to as "Pivot axis".

That is exactly what I was thinking of doing but the rule says I must use the "stock system of attachment." So is that "system" include the guide support (part #3 in the diagram) or is that "system" just the top vertical pin on the shock that goes inside the guide support or is it every thing in the picture part of the "system" because with out most of the parts it would not work as a "system".

Now add in that "Suspension bushings, bearings and ball joints are unrestricted"

I can no find any where that it says I can modify the bushing mount or holder. This is not a bump stop so I can't use that rule. To me that says I have to use the guide support but can use anything for part #7 since that is the rubber mount for the shock.

OK now can I make the bushing solid inside the guide plate and then have a bracket mounted to the bottom of a pin that goes inside this bushing and holds the upper rod in for the shock?

Something like this...



To me that meet all parts of the rules don't you think?

Edit for more info:

Looking around more on the site Ted posted I found another picture of the mount and it shows rod end mount bolted to the upper plate just like I am now thinking of doing but using the stock guide plate and a solid bushing.

I think the intent of the rule was to ensure we use the original body mounts for the shocks. Now if we can use any shock, it seems like we could use a adapter to connect it to the original body mount.

But if required to also use stock system of attachement?

If the adapter mounts to the original shock mount, is that OK??

Suspension bushings, are the shock mounts considered bushings?

Wouldn't it be better more clear if it said must use stock mounting points for shocks and left the shock and mounts free? Maybe it needs to be rewritten, what was the intent of the rule anyhow??

Yeah, I ended up modifying my upper mounts due to a similar problem-
short shocks don't have much travel! Gordon, those Opel shocks
get the shock body off the unsprung weight, but aren't much shorter... sadly.

It IS a good question- I'd say a strict reading requires a stud mount of
some sort, and converting to a heim joint (rather than a spherical bearing
with the stud through it) might be technically protestable. Maybe.

I think getting the point in the same place would be more important, from
a standpoint of competitive advantage. If you somehow modified the mount to
get extra travel, I could see someone plopping down a protest fee to see if the steward
agreed that it was a 'prohibited modification'... since running out of rear
shock travel's a big competitiive disadvantage, as I proved back in 2006...

t