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Just 1 More
10-21-2022, 02:58 PM
Can you convert a 4 link set up to the IRS? Well, I know you could but what I'm asking is how much modification is required or is it a bolt in swap?

michael everson
10-21-2022, 04:12 PM
Not at all possible. The frame is very different behind the passenger compartment

Mike

Just 1 More
10-21-2022, 05:19 PM
Not at all possible. The frame is very different behind the passenger compartment

Mike

Thank you

GoDadGo
10-21-2022, 05:42 PM
Have you thought about upgrading to the 3-Link with panhard bar?

RoadRacer
10-21-2022, 06:35 PM
Have you thought about upgrading to the 3-Link with panhard bar?

This. The 3-link is generally considered a big upgrade from the 4-link, geometry wise.

Just 1 More
10-22-2022, 11:02 AM
Have you thought about upgrading to the 3-Link with panhard bar?

Can this be done with the chassis already set up with the 4 link?

Papa
10-22-2022, 11:11 AM
Can this be done with the chassis already set up with the 4 link?

The current non-IRS chassis supports either 3-link or 4-link. You'll need the three-link parts from FFR. You'll need to confirm if your specific chassis supports 3-link.

Just 1 More
10-22-2022, 11:28 AM
Just watched the suspension video and it does say the 4 link is upgradeable to the 3 link

Papa
10-22-2022, 12:40 PM
I found this link that indicates compatibility with MK1, MK2, MK3 cars as well as the MK4.

https://www.factoryfiveparts.com/13181-3-link-retrofit-assembly/

GoDadGo
10-22-2022, 01:20 PM
Just watched the suspension video and it does say the 4 link is upgradeable to the 3 link

I know the MK-4 Chassis has the provisions for the upgrade.
I think the MK-3.1 also has those same frame provisions, but I'm NOT an expert.

EZ$
10-22-2022, 06:46 PM
I'm not absolutely certain, but I think CraigS did this some years back. From what I remember of the thread, it was not for the faint hearted. Hopefully he'll see this thread and respond.

EZ$
10-22-2022, 06:58 PM
OK, went back and double checked, Craig did do the swap to the 2015 IRS. https://thefactoryfiveforum.com/showthread.php?24546-IRS-upgrade-report

Apparently, it went well, and he's happy with it.

progmgr1
10-23-2022, 05:12 AM
Back in the olden days (before FFR offered the 2015 IRS option) some builders incorporated an IRS from other cars. The one I remember in particular adapted a complete rear suspension package from a BMW M3. The advantage was that it was self-contained and mounted on a subframe that had 4 floating mounting points. This was an "easy" job, but only because the builder had mad fabrication skills and patience.

Keith HR #894