4-link to 3-link conversion information

[marlin]

This maybe unique to my build and a few others with a similar configuration. And if nothing else it adds to the reservoir of knowledge. My kit a MK 3.1, which I bought 2nd hand, unfinished, and had been ordered as a 4 link. The prior owner gave me some of the parts for a 3-link and I ordered the rest from FFR. Additionally, I purchased the rear QA1 single adjust coil overs from Breeze.

The frame and solid rear axle needed some cutting and grinding work. The upper support on the right side (passenger) near the bulkhead needed removing for the front of upper link mount. And the stock supports on the axle needed removing for the anti-moan brake brackets to be mounted. (not part of 3-link conversion)
Everything mounted and sort of worked except I wanted a ride height of 4.5 front and 4.75 rear, living a mile up a gravel road. The rear spring adjusts for that height was at the very end of the threads and I was not comfortable with that. Speaking this over with Mark at Breeze we discovered 2 things. First QA1 has changed the coil over threads to be longer since I ordered the coil overs 2 years ago. But the other issue is the upper shock mounting holes were not low enough in relationship to the 3x2 support. This is a FFR change and it looks like since then they have lowered the weld bracket placement. This may not be an issue with the Koni shocks and if the ride height was lower again it would not be an issue.
smDSCN1766.jpg

In any event after some worry and with Mark's help an easy fix was obtained. QA1 offers a 1 and 2 inch extension to be placed onto the upper shock shaft that fits nicely into Marks custom locking nut. The 1 inch was long enough for me.
before DS.jpg

And additionally Mark has a 1 inch spring spacer that sits nicely on the lower spring perch. This combination gave the shaft the correct travel length and placed the lower adjusting nut at the center to lower part of the adjusting thread.
after DS with spring spacer.jpg

The only drawback of this fix is the lower spring spacer will have to be removed if I ever want to lower the ride height to less than 4.25 inches. The lower locking ring starts to hit the lower shock mounting.
Again only a few others might find this to be a problem but I’d like to thank Mark for the help in figuring this out.
Thanks, Marlin

[CraigS]

The other option is to buy a 10 inch spring. That's what I have used on mine since 2007 w/ ProShocks, DA Konis and DA QA1s.

[marlin]

That idea was discussed. According to Mark the concern is the shock shaft travel running out of length at an extreme extension. Doubt if I would ever reach the extreme travel but would rather be on the conservative side for safety sake. Thank for the thought though.

[R Thomas]

Thanks for posting this will be a big help in deciding which way I go.

[Ray W.]

I don't think this will be an issue for you with the Mk 4, R. My rear shock mounts look lower than those in these pics, so as stated above, it appears FFR has changed them on the new model.

Thanks for posting this will be a big help in deciding which way I go.

[myjones]

That idea was discussed. According to Mark the concern is the shock shaft travel running out of length at an extreme extension. Doubt if I would ever reach the extreme travel but would rather be on the conservative side for safety sake. Thank for the thought though.

The final product looks very well done but I saw a different/cheaper approach.

Did you consider making a box to slide into the original mount or is there something else that keeps that option from working?
The new drop mount box could bolt to the old mount through the original hole and have a new hole 1" lower.
As long as the box went clear up against the top of the original mount the compression load wouldn't be on the bolt itself and it looks like there is
a plate in the top of the FF mount that already has a hole in it for a second fastener to stop any twisting of the new drop mount box.

The win win would be both in total cost saved from the shock parts and how easy it would be to drop back to original ride height.
DB

[marlin]

Hi,
Thanks for the thought. Yes we did discuss this as an option. There were a couple of reasons I didn't go this route but others might find it doable. There is a weld bead both inside and outside the present "U"(inverted) bracket. Yes there is a flat metal plate on top with a hole that the 4-link shock (or a bolt) could go through. This bead could be ground off but may weaken the part. Also wasn't excited about welding a box on a finished car, having to redo the POR-15, etc. Bolting a box in place may also work but getting all the holes lined up would also be a challenge. Even if the bearing on the top of the coil over shock would be somewhat forgiving of a non perpendicular drilling.
Thanks for the troubleshooting idea. It's what the forums are all about.
Marlin