KW v3 Install plus suspension refresh advice

[wi54545]

I have been dumping a lot of money into my 1982 911SC. I have owned it since 2015 and have been slowly refreshing it. It was bone stock, previously owned by Klaus Selbert from St. Louis and Lindbergh Motorsports. Last year I removed the CIS injection, added PMO 46 carbs (will go to 3.2ss when that time comes, head studs still hanging in there). Removed all the AC and backdated the heat. SSI exchangers into an old M&K 2 in 2 out exhaust. Went to a 123 ignition setup for carbs with Porsche CDI. New Sheridan complete tinwear and shroud. I've taken quite a bit of weight out of the rear of the car. It runs pretty well (way better than it did) and sounds amazing. I love it.

Now to the suspension. It is all pretty stock (added turbo tie rods a couple years ago) and 40+ years old. The rear torsion bar bushings look smooshed. I've been wanting KW Variant 3 for a while and finally ordered them on 1/1/25. I just received them. That took 2 months. So, I'm thinking that I would like to add Eibach Anti roll bars front and rear. What would you guys recommend for torsion bars? Spring plates (will buy new and shiny)? I need a bumpsteer kit as well as I have the 19mm raised spindles on the KW's. Front bushings? Rebel Racing?

The goal is to have a precise handling street car that I can take on an HPDE once per year. I don't drive a lot, roads can be a bit rough in Western Wisconsin. Wife comfort is not a factor, she has our G87 BMW M2 for that.

Any recommendations? Advice?

[Mr. Merk]

We just completed an '88 Carrera project with KW V3. I followed Joey Seely of Emotion Engineering's recipe based on notes I've taken from him over the years:

-Stock torsion bars, in your case I think upgrading to 1986 25mm rear bars.
-Stock sway bars with adjustable rear links, again upgrade to 1986 spec 22/21 sways. Elephant also has a hollow adjustable rear sway bar that looks stock and is equivalent to the 21mm swaybar in its softest position. I'd love to try that. You'll probably need swaybar mount reinforcements if you're running sticky tires.
-Rubber spring plate and control arm bushings. We use Elephant
-Monoball trailing arm bushings
-Joey says monoball camber plates. We tried Tarett offset plates and WEVO monoballs, but they were both so clunky that we couldn't do it and ended up with stock. (One of my buddies has Elephant monoball conversion bushings in his 930 and is happy. We also have Elephant quick adjust camber plates in a 930 and they are quiet as well.)
-We used Tarett's bump steer kit on turbo tie rods. (FYI, the steering rack spacers have the opposite effect with raised spindles!)

[shoooo32]

I live in Milwaukee and oftentimes run those driftless farm roads west of Madison. They're pretty rough so you need some compliance in the setup. Adjustability was the big reason for my KW purchase as well. I haven't run them yet, but we're headed to Hill Country Rallye in a few weeks and I'll report back. I swapped the Eibach sway bars for Tarett's because the Eibach were binding/clunking in any position other than the middle one. I'm guessing this was an issue because I run the car pretty low.

My current setup (1978 Targa): 21/27 torsion bars, Rebel RSR control arm and swing plate bushings, Tarett sway bars, 19mm raised KW V3s, "sport rubber" rear control arm bushings and strut mounts, turbo tie rods and Tarett adjustable bump steer kit, 7&9x16 Fuchs w/300tw tires.

[Bill Verburg]

Originally Posted by wi54545

I have been dumping a lot of money into my 1982 911SC. I have owned it since 2015 and have been slowly refreshing it. It was bone stock, previously owned by Klaus Selbert from St. Louis and Lindbergh Motorsports. Last year I removed the CIS injection, added PMO 46 carbs (will go to 3.2ss when that time comes, head studs still hanging in there). Removed all the AC and backdated the heat. SSI exchangers into an old M&K 2 in 2 out exhaust. Went to a 123 ignition setup for carbs with Porsche CDI. New Sheridan complete tinwear and shroud. I've taken quite a bit of weight out of the rear of the car. It runs pretty well (way better than it did) and sounds amazing. I love it.

Now to the suspension. It is all pretty stock (added turbo tie rods a couple years ago) and 40+ years old. The rear torsion bar bushings look smooshed. I've been wanting KW Variant 3 for a while and finally ordered them on 1/1/25. I just received them. That took 2 months. So, I'm thinking that I would like to add Eibach Anti roll bars front and rear. What would you guys recommend for torsion bars? Spring plates (will buy new and shiny)? I need a bumpsteer kit as well as I have the 19mm raised spindles on the KW's. Front bushings? Rebel Racing?

The goal is to have a precise handling street car that I can take on an HPDE once per year. I don't drive a lot, roads can be a bit rough in Western Wisconsin. Wife comfort is not a factor, she has our G87 BMW M2 for that.

Any recommendations? Advice?

What wheels and tires are you running?

Is the existing body roll objectionable to you?

What ride height are you planning on?

Do you want to increase, decrease or leave the over/under steer character of the car as is?

In general increasing suspension stiffness decreases mechanical grip but at the same time reduces the loss of mechanical grip due to roll geometry changes.

increasing front spring more than rear reduces over steer and vice versa.

When the car is lowered in front 3 things happen
1) shock travel in bump is reduced, at the extreme the shock is riding on the bump stops
2) roll geometry is adversely affected, this adversely affects roll rate and suspension settings
3) bump steer is increased, bump steer aka roll steer can never be eliminated just reduced to a level that the driver can live w/

raising the spindles 19mm as in your KWs addresses the first 2 issues, the low end of stock front is 108+5mm = 113mm, so w/ your KWs a ride height of 132mm returns items 1 & 2 in effect back to stock

when the spindle is raised the outer end of the tie rod is also raised, this counters some of the effect on item 3, at 130mm +/- no rack spacer is needed w/ 19mm raised spindles as the raised outer end matches the amount that the steering rack drops from lowering

if the car is further lowered, again, bump travel is reduced and the difference in steering arm end heights are increased, go down another 11.5mm and now the steering rack needs to be raised by 11.5mm to match, 11.5 is about the max for steering rack rise w/ spacers.

continue to further drop the chassis and eventually the adjustable height steering knuckles become necessary

[wi54545]

What wheels and tires are you running?

Stock 16" Fuchs 205/55/16 225/50/16

Is the existing body roll objectionable to you?

The car feels very loose. I would like it feel more firm in this area.

What ride height are you planning on?

I just measured the fender heights as it sits. I haven't touched the height personally. This height or slightly lower.

25.25" Right Front 24.75" Left Front
24.5" Right Rear 24.625" Left Rear

Do you want to increase, decrease or leave the over/under steer character of the car as is?

I just want it to be more confidence inspiring if I take it on track someday. My home tracks are Brainerd and Road America so longer straights and fast sweepers. Perhaps neutral to slight oversteer. Don't want bugs to be hitting the back window per say. I'm a novice that has completed DT in the M2 which is very easy to drive fast.

Thank you so much for the write up!

[wi54545]

Originally Posted by Mr. Merk

We just completed an '88 Carrera project with KW V3. I followed Joey Seely of Emotion Engineering's recipe based on notes I've taken from him over the years:

-Stock torsion bars, in your case I think upgrading to 1986 25mm rear bars.
-Stock sway bars with adjustable rear links, again upgrade to 1986 spec 22/21 sways. Elephant also has a hollow adjustable rear sway bar that looks stock and is equivalent to the 21mm swaybar in its softest position. I'd love to try that. You'll probably need swaybar mount reinforcements if you're running sticky tires.
-Rubber spring plate and control arm bushings. We use Elephant
-Monoball trailing arm bushings
-Joey says monoball camber plates. We tried Tarett offset plates and WEVO monoballs, but they were both so clunky that we couldn't do it and ended up with stock. (One of my buddies has Elephant monoball conversion bushings in his 930 and is happy. We also have Elephant quick adjust camber plates in a 930 and they are quiet as well.)
-We used Tarett's bump steer kit on turbo tie rods. (FYI, the steering rack spacers have the opposite effect with raised spindles!)

Thank you!

[Mr. Merk]

Originally Posted by wi54545

What wheels and tires are you running?

Stock 16" Fuchs 205/55/16 225/50/16

The car feels very loose. I would like it feel more firm in this area.

The biggest improvement you'll make is widening your wheels to 7s & 8s with a really sticky tire.

I currently have the same sized tires stretched out over 8s & 9s. They are NOT very sticky DWS06 which feel TERRIBLE on 6s & 7s, but they feel nice and tight on the 8s & 9s. They are stretched and I wouldn't recommend this to a customer.

I've put 39 tires on my car in my ownership and these are the only all-season tires and the only tire over 200 treadwear I've ever used. I'm just playing around because I had some laying around that needed used up.

What make & model tires do you have installed?

[Bill Verburg]

Originally Posted by wi54545

What wheels and tires are you running?

Stock 16" Fuchs 205/55/16 225/50/16

Is the existing body roll objectionable to you?

The car feels very loose. I would like it feel more firm in this area.

What ride height are you planning on?

I just measured the fender heights as it sits. I haven't touched the height personally. This height or slightly lower.

25.25" Right Front 24.75" Left Front
24.5" Right Rear 24.625" Left Rear

Do you want to increase, decrease or leave the over/under steer character of the car as is?

I just want it to be more confidence inspiring if I take it on track someday. My home tracks are Brainerd and Road America so longer straights and fast sweepers. Perhaps neutral to slight oversteer. Don't want bugs to be hitting the back window per say. I'm a novice that has completed DT in the M2 which is very easy to drive fast.

Thank you so much for the write up!

You have several things that need to be addressed
1) nothing wrong w/ 205/55 & 225/50 perse but they really want 7 & 8s to get the most from them

2)when people say loose it usually means oversteer, I'm guessing that you meant it rolls more than you like which is normal for a stock suspension w/ at least ok tire grip

3) again just a wild a** guess but @25+/- " the car appears to have been lowered. By how much is hard to determine based on the data seen here, another WAG ~.5"


here's how to accurately measure front ride height on a 911


205/55 x 16 give an a of 11.9 to 12.2" , 303 to 308mm
a -b is he ride height, factory spec is 108+/-5mm, 120mm is lowered 12mm

stock over/under +/- a bit is where I'd stay, the more rear spring wrt the front the more oversteer, the more over the more the driver has to stay on top of the steering

20/25 t-bars puts you right where you are now, 20/26 a bit less under or more over depending on how you look at it, 20/26 gets rid of the most objectionable roll especially if you go from 20/18 to the late 22/21 roll baars, 20/27 more so and the suspension is getting uncomfortably harsh on anything but smooth roads, buyers choice here.

[ccallana]

Originally Posted by Mr. Merk

I currently have the same sized tires stretched out over 8s & 9s. They are NOT very sticky DWS06 which feel TERRIBLE on 6s & 7s, but they feel nice and tight on the 8s & 9s. They are stretched and I wouldn't recommend this to a customer.

not the OP, but just a comment... I'm running 7x16 205/55 and 9x16 225/50 with Michelin Pilot Sport A/S 4 ... I don't have much to compare to but they seem pretty sticky to me the 225 is pretty stretched on the 9" wheel... wanted to go with 245, but haven't been able to find an All Season in 245 on a 16" wheel. I could go with a summer tire I suppose

[Bill Verburg]

Originally Posted by ccallana

not the OP, but just a comment... I'm running 7x16 205/55 and 9x16 225/50 with Michelin Pilot Sport A/S 4 ... I don't have much to compare to but they seem pretty sticky to me the 225 is pretty stretched on the 9" wheel... wanted to go with 245, but haven't been able to find an All Season in 245 on a 16" wheel. I could go with a summer tire I suppose

225/50 x16 have a recommended wheel width of 6.0 to 8.0", putting them on a 9 is well outside their engineered range

putting them on a 6 makes for a softer floppier ride, max performance is from putting them on an 8

[ccallana]

Originally Posted by Bill Verburg

225/50 x16 have a recommended wheel width of 6.0 to 8.0", putting them on a 9 is well outside their engineered range

yeah - previous owner had this size, and so I just bought the same ones - only after that did I discover they weren't quite correct...

I've gotten mixed feedback from folks - some say shouldn't be a big deal (I have 7000 miles on them ... no issues so far) - some say really shouldn't stretch them that far..

I'm a bit nervous about moving to a summer tire just for those few weeks/months a year where the temps are a bit low (I'm in Northern California - don't drive in the snow, but mornings can be in the 30s/40s) - don't want to end up sliding around maybe I'm over thinking it... dunno.

[ccallana]

Forgot to add the photo to see the stretch

[PeteKz]

We just went through a long discussion with someone who is making suspension changes to his SC Targa. See this thread:https://forums.pelicanparts.com/porsche-911-technical-forum/1174139-trying-decide-suspension-setup-my-sc-targa.html

I'm in the minority, but I do not like the RSR/Tarrett solid front bushings or spring plate bushings. I would not install them again. I drive my car regularly and do hundred mile plus highway runs. On typically rough highways and side roads, they definitely transmit more noise and harshness to the cabin.

For a primarily street car, I strongly advise to stay with rubber bushings in the front A-arms and rear spring plates.

[Mr. Merk]

Originally Posted by ccallana

I'm running 9x16 225/50 with Michelin Pilot Sport A/S 4 ... I don't have much to compare to but they seem pretty sticky to me

the 225 is pretty stretched on the 9" wheel... wanted to go with 245, but haven't been able to find an All Season in 245 on a 16" wheel. I could go with a summer tire I suppose

The Michelin AS4 is a pretty good tire for daily driving. I can promise they are not very sticky, but they do feel very stable being stretched out on a 9" wheel. 8" really is the ideal wheel width for that size tire as previously stated.

Originally Posted by ccallana

I'm a bit nervous about moving to a summer tire just for those few weeks/months a year where the temps are a bit low (I'm in Northern California - don't drive in the snow, but mornings can be in the 30s/40s) - don't want to end up sliding around maybe I'm over thinking it... dunno.

Summer tires are where it's at on a 911. Having two sets of wheels is awesome, or just leave it in the garage when its cold.

Originally Posted by PeteKz

I'm in the minority, but I do not like the RSR/Tarrett solid front bushings or spring plate bushings. I would not install them again.

I strongly advise to stay with rubber bushings in the front A-arms and rear spring plates.

I'm with you. I had the RSR bushings and decided to use rubber.

Joey is a suspension engineer. He has a proven winning record with Porsche. He spent 15 years developing the infamous "Project Nasty" and explains why the cars need rubber in certain locations and why monoballs work in certain locations.

[Bill Verburg]

Originally Posted by ccallana

yeah - previous owner had this size, and so I just bought the same ones - only after that did I discover they weren't quite correct...

I've gotten mixed feedback from folks - some say shouldn't be a big deal (I have 7000 miles on them ... no issues so far) - some say really shouldn't stretch them that far..

I'm a bit nervous about moving to a summer tire just for those few weeks/months a year where the temps are a bit low (I'm in Northern California - don't drive in the snow, but mornings can be in the 30s/40s) - don't want to end up sliding around maybe I'm over thinking it... dunno.

The side walls are in tension which reduces seat pressure, what I've seen happen is that even innocuous things like Maple Whirligigs get between the wheel and and tire bead, they work their way further in and you end up w/ a flat

I've run .5" over for winter tires and was always a little uncomfortable, 1" is nuts in MO

[shoooo32]

I ran 225/50/16s on a 9" wheel when RE11s were discontinued. I got a puncture going 80mph, and even though I pulled over immediately, the tire sidewall was destroyed. I was able to limp 70 miles to Columbus OH where they had some Kuhmo all seasons for me to finish my trip.

Long story short, if you want to run 225s get 8" wheels.

[Mtsurfposse]

Originally Posted by ccallana

I'm a bit nervous about moving to a summer tire just for those few weeks/months a year where the temps are a bit low (I'm in Northern California - don't drive in the snow, but mornings can be in the 30s/40s) - don't want to end up sliding around maybe I'm over thinking it... dunno.

Those temps will dramatically change tire compound interaction with road> Under 50 degrees ambient temperature will dramatically change how the tire compound reacts. My friend ran toyo's and got one season out of them and below 50 that tire was so hard he had to drive like a grandmother to keep it under control. At my mechanics advice I've been on Pilot S4's and have gotten great mileage and while I do feel a change in grip somewhere in the sub 50 it is not dramatic.

[wi54545]

Thank you guys for the advice! Looking at the car it looks like I need all new bushings. The spring plate cover is touching the torsion bar tube. So, I've been agonizing on what to do. Rebel Racing RSR bushings front and rear, elephant rubber, or Uro to do it cheap. I'd like to change to the quickchange spring plate from Elephant at least for the adjustability, aka future proofing.

From you guys that have done the Rebel RSR, is the NVH bad? Most the roads are farm roads as stated before that can be rough in places. I do have a loud exhaust with Carbs and SSI with M&K exhaust. How long has the rubber from elephant racing been holding up? I just don't want to do this again unless its cheap, aka Uro.

So what I've got now is new Ball joints, KW var 3 19 raised spindles shocks and struts, Eibach Sways, stock torsion bars.

For street use rubber or sport rubber is by far the best way to go

[Bill Verburg]

Originally Posted by wi54545

Thank you guys for the advice! Looking at the car it looks like I need all new bushings. The spring plate cover is touching the torsion bar tube. So, I've been agonizing on what to do. Rebel Racing RSR bushings front and rear, elephant rubber, or Uro to do it cheap. I'd like to change to the quickchange spring plate from Elephant at least for the adjustability, aka future proofing.

From you guys that have done the Rebel RSR, is the NVH bad? Most the roads are farm roads as stated before that can be rough in places. I do have a loud exhaust with Carbs and SSI with M&K exhaust. How long has the rubber from elephant racing been holding up? I just don't want to do this again unless its cheap, aka Uro.

So what I've got now is new Ball joints, KW var 3 19 raised spindles shocks and struts, Eibach Sways, stock torsion bars.

For street use rubber or sport rubber is by far the best way to go

For street se rubber o sport rubber is by far the better way to go

[LukasM]

Over here in Europe lots of people are using Powerflex polyurethane bushings with great success, especially the new grey Heritage line. Approx. the same hardness as stock rubber, however doesn't deform over time and is supposed to last a lot longer. With the right grease I don't recall anybody every complaining that they are getting squeaks.