Help me out here. My car just got unloaded from the ship and will be in my possession in a matter of a couple weeks. Still hung up on suspension components. 90% track car, but I plan on driving it around town from time to time as well. Not commuting, but just joy rides to the gym, grocery store etc. you get the idea.

The car is a boxster 4.0. Mods will include harness bar/harness belts, TPC DSC controller, soul race exhaust, Apex SM10 19” wheels for wider tires front and rear and AP Racing radi cal brake kit front and rear. Yeah baby I’m all in. Most of this I have already except the brakes which I just got figured out. The remaining issue is the suspension.

I’ve been through this process before with my 981, so I’m familiar, but with the previous car I used GT3 front LCA’s with shims and rear toe control arms. I want to do the same thing with this car as I will need between 2.5-3.0 negative camber. The difference is that I am thinking about going with SPL parts which would eliminate the rubber bushings. I just have this in the back of my head that I might not be very happy with this set up when I get ready to take someone in the car for ice cream or the wifey wants to drive it. The issues I am concerned about most are noise and harshness.

Does anyone have any experience with SPL lower control arms and how those behave on the street? I know they are good for the track and that’s what I’m looking for (remember this car will be mostly a track car), however I just don’t want the harshness and noise to be a major buzz kill when I do drive it on the street from time to time.

Even if you don’t have experience with SPL in particular if you have experience with this situation and switched from rubber bushings to solid or no bushings I would like to hear from you.

Thanks!!

Sid

 

Go solid. My car usage is pretty much what you described. Going solid was a big difference for me. It holds the camber so much better. Before that, it felt like no amount of camber was sufficient. Noise was the same for me. In terms of ride it made me feel the dampers a bit more, which are a bit underdamped in the high speed imo.

 

OK thanks for your input. That is exactly what I am leaning to. Hoping to get more input on this, but not getting much traction (pardon the pun). Need to figure out which suspension component company I want to jump in with. I set up my 981 with tarrett and they have a great product and were good to work with. I am looking into RSS which also look good and also SPL parts. SPL has a unique method for the design of their lower control arms which I like, but I have not fully decided yet.

 

After some research I ended up with RSS

 

I would also urge you to consider Demon Speed. Our products are high quality made from the best materials for the job. Most are designed based on the Porsche Motorsports parts for the cup or RSR parts that we work with. We not only sponsor Rennlist, but we are also PCA club racing national sponsors as well.

Take a look at what we offer. Also, take a look at our videos on the subjects. Here is a link for the videos.

Demon Speed Motorsports Product Videos - YouTube

Also, there is a coupon code for Rennlisters called Rennlist for a percentage off the Demon Speed manufactured products.

I was actually going to mention in a different post that we have the Porsche Motorsports 997 Cup control arm outer halves back in stock.

Thanks

Ed

 

Hi,
Are the solid bushing (rod bearing etc.) in your control arms replaceable or do we purchase new sets once the joints gets worn and rattle?

 

I just swaped all mine, nothing but smiles. Totally transformed the car for the better. Nothing negative to say about going full metal.

 

swberry, you mention a harness bar as one of the mods you plan. What bar are you using? Most of the bars I have seen seem to be for Caymans.

 

Correct! But…. I do have a harness bar that is sold by competition Motorsports for the 718 cayman. From what I can see this bar will attach to the boxster onto the same structural attachment points. The only thing is that the plastic trim pieces are different from the boxster to the cayman. I will not be able to use the pre cut trim they sell as part of the kit. I will also have to modify the firewall insulation to wrap around the bar or possibly bolt the bar directly on top of the insulation and onto the attachment point.

I am still trying to decide about the harness bar, but I will likely do my first few track days with just the seat belt and see if it in combination with the LWBS will keep me planted enough in my seat without being tossed around too much.

 

Hard to beat tried and tested OEM Porsche Motorsport suspension components with their Hirschmann heim joints and Valcomax trunnion pins throughout. I've been using these for many years. The pinch mechanism on the toe arm / tie rods makes adjustment very precise and a breeze.