Suspension upgrade, vented disc brakes, Porsche wheels +more

[raygreenwood]

Oh...thats not bad at all. It just looks worse in the pictures. What you have is not that excessive compared to many I have seen that drive fine. But the other worry is this. Your parts are new. As that donut compresses...the gap will grow...and the rebound length increases. It may get too close to the hood. You don't want to start out with a gap that is servicable...but marginally large...and end up in 3k miles with too much gap......though fixing it is just minutes unless the donut is toast.

As I'm sure you have found, you can simply loosen the nut with car sitting on its wheels, remove the cone and spacer and adjust what you need to. The spring may unload slightly but usually a foot on the bumper gets everything back to where it needs to be so you can put the nut on. Ray

[vwbill]

Hey Guys, I measured my gap and found 6mm on the driver side and 9mm on the pass side!! I thought maybe I set my Koni's wrong when I set them with one firm and the other soft?? I think you have to set them out of the strut tube? A pull and turn thing fully extended... So to adjust the gap do you just space with washers at under the strut nut and cap? Bill,jr.
p.s.It's been too long since I rebuilt them.

[nick sparrow]

all I can say is wow you guys have done some really serious work here, it has inspired me to take another look at my wagon......

nick

[Bill K.]

As I'm sure you have found, you can simply loosen the nut with car sitting on its wheels, remove the cone and spacer and adjust what you need to. The spring may unload slightly but usually a foot on the bumper gets everything back to where it needs to be so you can put the nut on. Ray

Aahhh. I wasn't thinking or reading straight until I read this. I was talking about shortening my custom spacer BELOW the strut bearing to decrease the strut cap-to-bearing gap (that would just lower the car). Now it is obvious that the strut cap-to-bearing gap is controlled by the stock height 13mm strut bearing spacer as shown below.





The stock height 13mm spacer extends about 2.75-3.00mm above the strut bearing, so the gap can be reduced about 2mm if desired.

Hey Guys, I measured my gap and found 6mm on the driver side and 9mm on the pass side!! I thought maybe I set my Koni's wrong when I set them with one firm and the other soft?? I think you have to set them out of the strut tube? A pull and turn thing fully extended... So to adjust the gap do you just space with washers at under the strut nut and cap? Bill,jr.

The gap is not related to the Koni dampening setting, just the condition of the rubber surrounding the strut bearing and the height of the strut bearing spacer. To adjust the "Special D" adjustable red Koni's the strut rod is fully compressed into the strut cartridge and rotated counterclockwise to engage the adjuster tangs, then turn clockwise for increased rebound stiffness and counterclockwise to decrease rebound stiffness. The difference in stiffness from full soft to full hard is typically 100%. Wally reports a good ride at 1/4-1/2 turn from full soft with the BMW coils. See here for more.

Mine are set full stiff and result in a slow rebound with I believe to be the source of the harmonic bobbing up/down at lower speeds. It should be adjustable with the strut insert installed - I'll find out today...

[Wally]

Full stiff is really not a good idea. 1 full turn inwards is about max what I would run. You can feel it yourself while tryining to pull the shock in and out. Out will be almost impossible at full stiff. 1 turn in is just about doable. Try that first I would suggest, then go stiffer when the desire is there
I would also shorten the spacer about 2mm. Mine were just above the larger disk/plate as well. You just need to clear the plate below to not have resistance, bit are still turning without problem.

[Bill K.]

Adjustments:

* Set strut rebound to 50% (1 turn clockwise from full soft)
* Shaved strut bearing spacer to 11 mm
* Replaced spacer under strut bearing with washer stack to lower car additional 8 mm
* Replaced damaged spring plate bearing

The adjustment to the strut rebound stiffness solved the bobbing harmonics. Now the compression stroke is about the same speed as the recoil stroke when the front bumper is stepped on.



The strut bearing spacer was ground down from 13mm to 11mm resulting in a 1.5mm gap above the strut bearing for clearance to the strut cap. The strut cap-to-bearing top dimension that was 6mm is now 4mm.

On original installation, the spring plate bearing was damaged by not having the strut rod spacer aligned with the ID of the spring plate bearing. The bearing was replaced.



The spacer under the strut bearing was found to be digging into the top of the spring plate bearing on the damaged side, so larger diameter washers were used to distribute the load over a larger area while lowering the car a bit. The top of strut rod to trunk gap after jumping on the bumper is 1/4" minimum using the Play Doh method.







The handling and ride are great now. It turns in on a dime!

[raygreenwood]

Yup!...you got it going on now! What you found with that spacer is exactly what I have found. The sad part is that there is enough variation in bearing cartridges that the next bearing may need the long spacer Nice work! Ray

[MGVWfan]

Damn what a fine job. I think the guys that designed the T4 would nod their approval at your upgrades to their work. You are Da Man!

[Bill K.]

Front struts shown here now for sale: http://www.shoptalkforums.com/viewtopic ... 5&t=131230

[raygreenwood]

The mazda thrust bearings made a big diffeerence in turning effort and smoothness on mine. How did they do for you? Very nice work! Ray

[Bill K.]

Yes Ray. Another good idea from you. The Mazda spring plate bearings with the 1303 strut bearings make it turn very smooth and quick. I'm making another set, so these are for sale.

[raygreenwood]

I'm so glad there are more people "carefully" modifying and testing parts and mods for the 411/412 now.
As everyone has found who works on these....the balance of parts quality, tolerance, tension and pressures takes a lot of testing and careful decision making. These cars do not respond well and safely to sloppy attempts at modifying the suspension.

Bill, Wally and everyone else...your efforts are really going to help even basic street car versions of these cars to survive. Having only had about 3 years of my driving life....where I didn't own and drive a 411 or 412....I have spent endless hours working on them and modifying them. For a long time I only modified them simply because....normal stock parts were scarce...and still are.

We have no real engine issues. We can work around scarcity of transmission and interior parts. but when you can't get brakes or suspension parts...the car is not drivable.

Good work Bill, Olaf, Walley...and everyone else here! Ray

[nick sparrow]

I can see I must spend some more time on here. I will need to take notes of what has been done, such creative thinking by you all most impressive. I have not done too much to my type 4's for a while now and keep looking on here at what has been going on....very inspiring and makes me want to spend some more time in the lock-up. My problem is too many cars to tinker with right now.

regards

nick sparrow

[Bill K.]

V3 now with 205/50 front tires and strut rod spacer.



I like the 205/50's in the front - fill out the arch better, restores speedo accuracy, allows front/rear tire rotation, and provides a bit softer ride quality.

The strut rod spacer fits over the large diameter section of the strut rod to increase the gap between the spring plate and the strut bearing by compressing the spring more. The strut rod spacer is the aluminum part between the Mazda spring plate bearing and the strut mount bearing. This configuration is compatible with 73 and earlier strut mounts also. V2 design resulting in rubbing between the spring plate and the strut bearing housing when the strut bushing deflects under heavy load. V3 strut rod spacer restores the stock gap whereby the rubber strut mount bushing can deflect to maximum without contacting the spring plate. Also, the strut rod spacer permits use of the Audi 4000 strut insert with E30 M3 springs without strut rod extension.



To fit the 205/50's, 12mm spacers with 52mm studs were needed to prevent tire rubbing the lower spring perch.


Also, the fender lip has been rolled and the steering lock reduced to prevent tire rubbing the fender at full steering lock. The steering lock is now 2.5 turns lock-to-lock which works for city driving just fine.

The result is 1.5" bump travel to bump stop (no compression; 2" travel including bump stop compression), 2" droop travel, front is lowered 5/8" vs rear along the rockers. The front fender apex is 24-7/8" off the ground. Loading the trunk for a camping trip lowers the front another 1/2". I'm happy with these results and will lock-in on V3.

In summary, V3 is:
* BMW E30 M3 springs
* Audi 4000 strut inserts, un-modified
* Stock 412 strut tubes
* BMW M3 bump stops
* Modified 412 upper spring plates with Mazda spring plate bearings
* Custom strut rod spacer
* Custom strut insert spacers -radial and lower
* Compatible with 74 or 73 & earlier strut bearings
* Compatible with up to 205/50/17 but requires rolling fender lip and limiting of steering lock to prevent rubbing

[sharkskinman]

so 12mm spacers
changing the ET53 offset to a ET41 offset

i ask because im thinking about using adapters
wich are 25mm or 1" thickness and porsche wheels that are 50-60mm offset

i have a pair of turbo twists i will probably fit to see
with adapters

i Really like the stance of your car now
and as it seems
i could put 18s on it like a euro tuner

Looking Great man!!!