Single adjustable shocks

[Sailkane]

PCA rules for Autocross allow single adjustable shocks. I have a 911 SC and would like to hear if anyone has single adjustable shocks , what type and a review of there performance.

I also just purchased 15” rims 7 &8” . Has anyone used 225/45 and 245/40?
Any fit issues?

[Driven97]

225/45 245/40 on 15x7/15x9 BFG Rival S. Look a little stubby but the thrust / gearing boost is nice for AX. Wheel wells have plenty of room for the tires, but as always, offset and alignments can put the tires in the wrong spots.

I have non-adjustable front shocks and double adjustable rears. IMO, it's easy to get yourself into trouble with knobs if you don't know what you're doing. It's easy to mis-identify handling issues, tune the wrong way, over tune, etc. A set of fresh-ish non-adjustable shocks decently matched to your torsions and focusing more on the driving will likely be the better route for most people.

Of course, if you're familiar and sensitive to what the car is doing in transition through all of the phases of a corner, have the patience to test objectively (with data) and take notes, you can probably tune a set of singles to suit your driving style very slightly better than non-adjustables.

I do like having doubles in the rear, but a lot of times I'd rather not have those knobs to think about between runs. I had singles (Koni yellows, rebound adjustment only) on my other (non-911) competition car and I pretty much stuck to one setting on all but the roughest of sites.

[Trackrash]

Check my GARAGE for my car's details.

IMO the shock to use for adjustability is the Koni yellow sport shocks. They are EXTERNALLY adjustable. So adjustments can be made between autocross runs. I find this is very helpful to fine tune my car's handling.

You didn't mention any other mods, like bushings, torsion bars or sways on your car.

Many will find that Bilsteins work great, if tuned for the car and its suspension. Just no adjustability. I have no idea why Bilstein doesn't make adjustable shocks for the torsion bar cars.

[jpnovak]

Koni shocks were delivered on many 911s from the factory starting with the SWB cars (and 356 if we are going back that far). Konis are rebound adjustable. They are available in many variants. The sport adjustable are what you would want for your car. As Matt said, Make sure you understand what you are doing. Too much or too little damping is not a good thing.

[Cory M]

Single adjustables basically change the rebound and the compression (to a smaller amount) at the same time. All of the literature you'll find, troubleshooting guides, etc assumes you have at least 2 way adjustable shocks and you can change the rebound and compression independently. Many books assume you have 4-ways and can tune the high and low speed separately too. I've got JRZ singles on the front of my car and feel like the tune-ability is a lot less than the doubles I have on the rear. I'd still rather have single adjustable than nothing though.

Many club racers, who are limited by rules, have Bilsteins revalved to match their set ups. This is a pretty good option, especially for the price, but you won't be able to tune out bumpy surfaces or adjust the handling with the shocks. You'll have to make your changes with tire pressures, sway bars, and maybe alignment settings if you have time on race day.

You can get adjustable Bilsteins from Tarett, Rebel, and Elephant. The next step up to JRZ, MCS, Moton, Ohlins, etc is a big one in both performance and dollars. Make sure whatever you buy has good options for service centers, hopefully locally. It's a pain to have to ship your struts across the country for a rebuild and wait for them to get finished.