Full Suspension Design/Build/Install
 

Merry Christmas everyone!! I wanted to document my suspension update for anyone interested with the parts I have built and decided to start this thread to separate it from my LCA discussion as there will be a bunch of parts other than the LCAs that are going to be installed that I will also share. For transparency, the parts I will install have all been modeled with detailed drawings by myself, taking reference dimensions from the car, OEM parts, a few aftermarket parts, and machined working with buddies’ in their shops. A few parts are still to be built.

I will note materials used, if anyone is inclined to know about that stuff. All parts have been subjected to FEA through Solidworks simulations to analyze potential functional loads on various load axes/directions. I won’t go into detail as any given part will have many scenarios simulated.

The inner monoballs and outer arms are machined from 7075-T6 with the outer modeled after the OEM 996 adjustable LCA. Bearings are Teflon lined FK COM12T with F1 fit. Bushings are 4340 with metric grade 10 fasteners with the outer bolt upsized to 14mm. Grade 12.9 threaded rod is permanently Loc-tited into the monoball end with M8 jet nuts connecting the inner and outers with 6061 aluminum spacers to increase arm length and also take up threaded rod extension. All aluminum is hard anodized.

Both bearings are interference press fit and utilize bearing retaining compounds and heavy-duty Spiro-loc type internal snap rings.

Here are some shots of the installed arms from various perspectives.
https://i.ibb.co/JqtN3jL/2-EF57485-8...1-A626-BCE.jpg

https://i.ibb.co/7vvSt0L/Top-14mm-Up...connection.jpg

https://i.ibb.co/FKTxNjr/Side-Front.jpg

https://i.ibb.co/hBLcBV9/Side-rear.jpg

Here is a shot using an adjustable hand reamer to enlarge the upright hole to accommodate the 14mm fastener. I could have bought a 14mm drill with a shank small enough to fit a hand drill but had this and it sufficed fine. The family was not happy having to pick aluminum shavings out of the pizza. :D

https://i.ibb.co/pW3b3bW/Upright-reaming.jpg

Adjustable hand reamer set.

https://i.ibb.co/q73hfmd/Reamer-set.jpg

Wow outstanding work!!!!

dood.... you always impress.
BEAUTIFUL!!!

Full Suspension Design/Build/Install
 

Some other parts ready to install after anodization.

Pinch style toe arms, tie rods, and toe lockouts. Arms are again 7075-T6 with 17-4 stainless spacers and cone inserts. Toe lockouts are 4340. Rod ends are FK JMX/L 10T with F1 fit. Grade 10/10.9 hardware with ARP 12 point screws for the pinch point.


https://i.ibb.co/z5BJsWK/46-FFE258-F...B1-CAA9-FA.jpg

https://i.ibb.co/CH0fH4J/D0-ACAB11-9...3-BF9386-C.jpg

https://i.ibb.co/RBLYF32/1-ADA6646-B...540-CCC5-F.jpg

Full Suspension Design/Build/Install
 

Parts anodized and installed. Thrust arm forks built. Working on the thrust arm center links.

https://i.ibb.co/TMxGsRp/117-E146-F-...C2-C6-ACEB.jpg

https://i.ibb.co/N9xZsmG/AA4-F3-C54-...34-FBFBF34.jpg

https://i.ibb.co/ZdHyrtf/915-B72-DD-...664-FFF4-A.jpg

https://i.ibb.co/V3Swg6Y/1-D53-D980-...-AD096-FE7.jpg

https://i.ibb.co/mygvvq4/5458-E525-4...D48-E5-A36.jpg

https://i.ibb.co/Tv3HdBs/80-F6-EFF7-...1-EBDC7-BC.jpg

https://i.ibb.co/QbHsqg3/16531158-BB...28-FCB5210.jpg

Wow nice stuff!

Yeah! +10000000000

Very Nice!!

Are you going to be selling these?

I'd be interested in lower control arms that had raised ball joints to allow you to lower the car without effecting the roll center (you'd be able to lower the car more without the control arms pointing up). These are common on older 911s but no one is making them for newer 911s...yet.

Porsche offers tapered studs of varying lengths to accomplish this in their racing parts catalog though I can’t seem to find where I had the document saved.

Once I get everything buttoned up I will play around with making some tapered bushings of different neck lengths and longer bolts to lower the upright attachment point to improve roll center geometry.

Keep us posted I would be interested in a set if they can improve the roll center.

Finished some thrust arm center links and am finalizing rear monoball mounts with an adapter plate to facilitate mounting the Ohlins coilovers.

https://i.ibb.co/nbHs8Wn/Thrust-arms.jpg

Very Very Nice!

Wow. Just wow

Fantastic - Haven't had a chance to comment and glad the thread moved up the stack.

Roll center, bump steer adjustments, excellent - Too bad it isn't SPB legal.

Spec 944 allows spherical bearings, why not SPB. Far cheaper and easier than replacing the Porsche stock rubber ones.

Well maybe if Todd is willing to make them really available, we can petition for an allowance in the rules next year? [emoji6]

Sent from my SM-G970U using Tapatalk

Yeah I have never understood the restrictive rules of SPB concerning power/suspension. There are/were faster 986 S cars than some SPB cars. Looking at you Maytag... your Blue Bullet... RIP...

Rear Monoball mounts are now completed with a plate to adapt Ohlins R/T coilovers for installation with the monoball mounts. As seen in the pictures below, the Ohlins set comes with a mold formed rubber insert that fits into the OEM strut mount and locates on the three OEM strut mount stud heads. A machined aluminum part then fits into the bottom side of the rubber insert in the Ohlins kit. The machined part has a lip with an OD that mates with the spring.
The Ohlins rubber piece is so large and has such a radius that making a monoball mount that would still fit properly in the car body and have sufficient wall thickness was not possible so I designed and built a different aluminum insert that would locate on the stud heads, be flush with the bottom plate of the monoball mount, and have the correct lip/OD to mate with the Ohlins springs.

https://i.ibb.co/pQdzBvq/Ohlins-Rubb...ate-bottom.jpg

https://i.ibb.co/pQdzBvq/Ohlins-Rubb...hine-plate.jpg

A rubber washer supplied by Ohlins sits between the aluminum lip and the spring. Inside the cup is a FK Com14t F1 fit spherical bearing captured by a cap with 5 M5 screws. Bearing retainer compound will be used for the bearing locating surfaces with Loctite blue on all screws/nuts.

Here you can see the monoball, adapter plate, and spring from the side view.

https://i.ibb.co/SsPSvNH/Ohlins-mono...th-spring1.jpg

Here is the assembled monoball and coilover though I need to increase spring pre-load by 5mm. I couldn’t tighten the pre-load spanner nut any more by myself. Aluminum will be anodized blue.

https://i.ibb.co/h2W4Q68/Ohlins-mono...-coilover1.jpg

I am done with machining other than building drop link adjustment centers after getting everything installed and measuring what length centers I need to build for front and rears. If all goes ok I hope to get the car on the ground again this week. The only issue with this is I can’t get tires I want and the ones I had are completely done. Stupid Covid shortages of everything…

Holy Good golly my friend!
BEAUTIFUL work!
Incredible.
Truly.

Sent from my SM-G970U using Tapatalk

Ready for install...

https://i.ibb.co/b5ZLDfX/Ohlins-assembled.jpg

Setting spring pre-load by myself was a royal pain. I couldn't keep the assembly fixed to turn the nut for the last few millimeters

I kind of wish I had not installed anything yet and put everything out together for a full build picture.

You need some helper springs. No need to preload the mains. You still need to set ride height.

Is there anything you can't reverse engineer ... better than the original?

Everything looks great.

No. The answer is no: nothing he can't improve on.
Beautiful work!

Sent from my SM-G970U using Tapatalk

Ohlins kit for the Boxster only has the main spring. Height is adjusted with the nut riding on top of the hub upright.

I should come down to your garage at the track for the MaxD ride height, alignment, and corner balance special.

Full Suspension Design/Build/Install
 

A few installation pictures..

https://i.ibb.co/PZpGZcq/49-BB27-F6-...E3492-B581.jpg

1/4” anti-dive thrust setup

https://i.ibb.co/wNGM8P8/E9-BA9826-4...8-B66-D0-F.jpg

1/4” anti-squat setup

https://i.ibb.co/3Nfpfk1/485-F9-A25-...5-E9-B3-CD.jpg

https://i.ibb.co/jJ16GjP/8726-B3-DA-...-F581-AC37.jpg

https://i.ibb.co/4MvfMyZ/05-CB7-DE5-...-C725-EBFB.jpg

https://i.ibb.co/6vvgWHH/DAD0447-D-5...2-DFC31389.jpg

Intall and alignment are completed with 245/40 and 275/35 Hankook RS-4s mounted on Cayman S II wheels Hyperdipped black. Ready for first track event at the PCA event at Utah Motorsports Campus on 9/11.

Car is set at -3.2F and -2.8r and is a blast driving through the canyons and mountain passes in my area. I can't wait to get it on the track.


https://i.ibb.co/s38Qm3q/Black-Wheels.jpg

Very nice!
Give us a full report after your track days.

Nice stand, your car looks awesome! :cheers:

Wow! Incredible work. Awesome that you are in Utah as well. I'll be out on Sunday for my first track laps in my 4.2 swapped boxster, and hopefully that PCA event as well (knock on wood)

OP - how did the car do on track? Event was full by the time I tried to sign up. Looks as if there may have been some rain on Saturday. How was it?

Post track update:

The car was amazing!! So predictable and controlled without any rubber bushings anywhere outside of stabilizer bars. The Ohlins, upgraded stabilizer bars, new parts, and more camber transformed the car into, what the instructor I had called, a 'grip monster'. The RS-4s were great all day in both wet and dry.

I had five sessions with the first sprinkling rain, the second and third raining with a very wet track, and the fourth and fifth dry. This was my first time on track and by the end of the day I was finally able to push after familiarizing myself with the track, racing line, and car capabilities. I was pushing the high 3' 40s" on the Utah Motorsports Campus full track at the end of the day. I passed all non-911s in the last two sessions. It felt great passing 987/981 Caymans.

The car is way more capable than I am still after my first runs on the track and I really am bummed I won't be able to get back out until next April/May? The data show I should be able to pull quite a bit more time out by staying on the throttle on some high speed turns, braking later/harder and transitioning between brakes/throttle and back and forth quicker, and changing down another gear on a couple of low speed corners.

I have one to a few sets of everything I built for anybody interested. I was really happy with how the whole package performed.

https://i.ibb.co/QMBXHKv/805-C2208-4...EACE5-D557.jpg

Who'd your instructor end up being, Todd?

Mike Clarke. Great Guy. One fun note, he had a hat on that had the Porsche parts stamp logo on it. When meeting him, I said something along the lines, 'that is such a cool Porsche hat', and he said I was the first person to recognize it for what it is. I guess you have to work on them to know.

Here is a link to the hats. There are a couple of different styles.

https://datiheadwear.com/collections/partnerships/products/copy-of-stamp-of-authenticity-by-bretkowski-on-a-classic-trucker-mesh-back-hat