Is this Koni acceptable for track use?, 72-73 Red self leveling Options

[MikeSpraggi]

I have a pair of 72-73 911 "Koni only" struts with 3.5" SC calipers. The only Koni inserts I can find for them are sefl-leveling "reds". I am thinking of installing these on my track car that will be used for DE events for the foreseeable future. What is this "self-leveling" system these shocks use? I take it they are not adjustable shocks.

Will these shocks give me acceptable performance when pushed hard on my 1970 teener with 2.2 six semi-race engine? Koni "reds" will also be in the rear. Thanks.

[Richard Casto]

Mike, I think you are right regarding the "Red" (86 1638) as being the one that Koni says fits. I also agree with Eric that they are just saying "this does not work with the hydronumatic" strut.

To address your original question, it's my understanding that the "Red" are just not aggressively valved as the "Yellow". Also most of they yellow are adjustable via the "knob" on the top. While I think the adjustability of the Red is done some other way?

I would still call someone such as Jason at Paragon or Koni because I believe there are other combinations that will work than what is listed on the Koni fitment guide. I think some of the fitment guide is also based upon valving. For example if Koni has an insert with what they think is optimal valving for your application, they will list that particular insert. But if there is also another insert that will fit into the strut they will not list it. So I think they may have a "red" that is perfect, but there may be a "yellow" that might work. I think you can even get the "red" body revalved if it's not aggressive enough for you as is.

[MikeSpraggi]

Mike, I think you are right regarding the "Red" (86 1638) as being the one that Koni says fits. I also agree with Eric that they are just saying "this does not work with the hydronumatic" strut.

To address your original question, it's my understanding that the "Red" are just not aggressively valved as the "Yellow". Also most of they yellow are adjustable via the "knob" on the top. While I think the adjustability of the Red is done some other way?

I would still call someone such as Jason at Paragon or Koni because I believe there are other combinations that will work than what is listed on the Koni fitment guide. I think some of the fitment guide is also based upon valving. For example if Koni has an insert with what they think is optimal valving for your application, they will list that particular insert. But if there is also another insert that will fit into the strut they will not list it. So I think they may have a "red" that is perfect, but there may be a "yellow" that might work. I think you can even get the "red" body revalved if it's not aggressive enough for you as is.

Thanks for recommending Paragon. Apparently a "Yellow" 8641-1039 sport with a different gland nut will work. They're not cheap, but that's what I'm going with. Now for the rears ......... yellows also. Thanks all.