Which Koni Sports for 77 911S?

frankc · 11:33 AM

I am in the process of replacing most of the suspension components on my '77 911S (OE Koni struts) and have some questions about which Koni shocks I should be using (Time to replace 30 year old suspension - little help please?)

I would like the Koni's that are externally adjustable (knob at top). Even Koni's website is not clear about this. Are both the red and yellow (sport) shocks ext adjustable? Some indicate that only the Sports are, and others say both are. Then another source said only some Sports are.

I would like to go with the Sport inserts/shocks, so here is what I've come up with:

Front shocks:
It's rather clear that the Koni Sport insert (8641-1039S) is only available for Boge struts (which I find odd). However, Koni's site and others (http://www.koni-na.com/display.cfm?...submit=Continue)
say the Sport insert can be used with the Koni strut if a different Gland Nut is used ("8641 1039Sport front can be used with OE Koni struts if gland nut 73.25.01.011.1 is ordered as well.") Our host does not sell the gland nut, but I was able to locate it from Paragon. Is this the route that most people take with Koni struts, or do they stick with the Red inserts (86-1942)? And the 8641-1039S is externally adjustable, right?

Rear Shocks:
Koni's site lists two different rear Sport shocks available for my car: 30-1214S and 8210-1159S. Most sites that sell Koni's seem to offer only the first part number. The second part is more expensive. Paragon indicated the 30-1214S part is *not* externally adjustable. The 8210-1159S is ext adjustable, but it is a softer shock (even though designated "sport"), and it should be re-valved to match the Sport front. What do most people use for the rears when going with Koni's? It seems that the convenience factor would go way down having the fronts externally adjustable, but not the rears.

And what about the oil in the strut housing - some posts say leave it, some say replace it, some say dump it. It seems that if it is present in my strut (not sure about that), and that since I'm replacing it with another Koni, that I should leave it for cooling purposes.

thanks,
Frank

Wil Ferch · 01-17-2007, 10:42 AM

Look what I say here--->

Front Koni reds/Rear Koni Yellows?

- Wil

frankc · 01-17-2007, 11:31 AM

Wil,
That thread was very helpful. I wonder why it didn't come up when I searched for the Koni part numbers earlier?

So based on your post, I now have to decide whether to stick with my original plan of using Sport inserts, or go with the Normal inserts as you recommend. Ahhh, one more decision to agonize over. I received an email from Jason over at Paragon - I think I'll give him a call and see what he thinks.

But at least I know what to do about the rears now - 8210-1159S sounds like the way to go.

thanks,
Frank

Wil Ferch · 01-17-2007, 12:03 PM

Since this model "sport" is *relatively* soft....I think you're well served with normal RED fronts....both are top-knob adjustable anyway. Most 911's don't need excessive front shock valve control anyway.

- Wil

frankc · 01-17-2007, 12:13 PM

I just got off the phone with Jason at Paragon and things are starting to gel a bit. He recommended a setup like Wil's. That is, the non-sport gas strut, with the hydraulic (short body) sport rears. Both front and rear will then be externally adjustable.

He felt the hydraulic rears (8210-1159S) would be fine given the size torsion bars I plan to use (either 27 or 28), plus I wouldn't have to worry about the high-pressure gas strut (30-1214S) altering the ride height (as Wil mentioned). And the 30-1214S is not externally adjustable.

I guess the non-sport version of the Koni struts are preferred up front for the same reason the Bilstein HD's are used rather than the Sports. btw, both the Red and Yellow 8641-1039's are externally adjustable, just a valving difference.

Frank

frankc · 01-17-2007, 07:26 PM

I should have mentioned that the strut insert listed for the Koni strut (86-1942) is a hydraulic unit that is not externally adjustable. I wonder if this is simply the same insert that came with the strut when new?

DG624 · 06-11-2014, 03:11 PM

The biggest advantage to Koni sport shocks is the price. I have had some for over ten years but have been told that the adjustable feature is difficult to predict. Unless the shock builder considers the sprung and unsprung weight, wheel rate, spring rate, tire spring weight and other factors then you might as well use a non-adjustable unit that is made for your car. The shock design should not sacrifice the low speed movement for high speed stiffness.