3 link retrofit on a 4 link Mark 2

[MikeD]

My buddy and I installed a 3 link on his Mark 2 that he built 21 years ago as a 4 link.
We couldn’t find any videos on the process, so we made one.

It’s really not a bad project.

Here’s the video:
Factory five four link to 3 link
https://youtu.be/ArphKCxKzls

I think he said he spent 6 - 7 hours alone, then he and I spent another 5 -6 hours.

Quality time in the garage!
Miked

[CraigS]

I did that twice on a MkI and MkII. As you say really not that bad.

[GoDadGo]

I'd really like to hear your before and after comments and if this change made much of a difference.
Also, thanks for posting this and please give us your driving impression of the car now that you've done this upgrade.
As for me, my car is an Early 2015 3-Link MK-4 and handles great, but it is a bit rough riding compared to my friend's late 2015 IRS MK-4.

[weendoggy]

...
As for me, my car is an Early 2015 3-Link MK-4 and handles great, but it is a bit rough riding compared to my friend's late 2015 IRS MK-4.

That solid axle will NEVER feel like an IRS! I have the MKVIII/T-Bird IRS and did it from day one. The only solid axle I have now is my Tacoma and '02 Mustang w/panhard bar and neither ride like the feel of an IRS. I have buddies with solid axle 3-link etc. and they ride like a truck to me, but I'm spoiled. Another buddy built a MKIII and put the IRS in after owning his original MKI solid axle and he said he'd never go back! Hope your kidneys are in good shape.

[GoDadGo]

Hope your kidneys are in good shape.

I really would like to know if his car feels & handles better since he did this upgrade.
While the IRS rides really nice, the 3-Link is the best option if you prefer drag racing over auto-crossing.
Also, my kidneys are great and Redbone's 60' times have improved since the change from Nitto 555's to NT-05's.

[Flip Smiley]

Phil here. Weather permitted only a short test drive. Definite improvement. More responsive better handling. Weight seemed to be transferred to where the traction was needed. Less squat on hard acceleration and additional body roll on cornering. Stiffer ride with less chop may be attributed to new springs that replaced the worn Mustang units. I know the IRS is superior but I opted for the bolt on 3 link for installation on a finished car. These are my non-professional observations but I am confident that there a quite a few donor built MK1 and 2's with stock Mustang 4 link rear suspensions that could benefit from this upgrade.
Best regards and good luck

[weendoggy]

These are my non-professional observations but I am confident that there a quite a few donor built MK1 and 2's with stock Mustang 4 link rear suspensions that could benefit from this upgrade.
Best regards and good luck

I installed one on my buddy's car when they first became available. He has a MKI and it did make a huge impact on keeping the car planted. Anything is better than the stock Mustang suspension.

[CraigS]

No question irs is better but, when I did my 4 to 3 link, I kept the same coilover shocks/springs. To me the ride was not that much different in normal driving going straight on reasonably smooth roads. After all w/ the same solid axle, and the same springs and shocks, the car isn't going to react much differently to hitting the same bump. Where I felt a difference was when the road got curvy AND had bumps in the curves. There the lower roll center of the 3 link really helped keep the rear planted. Later on the MkII, I retrofitted the 2015 irs. Now that really made a big improvement in curves w/ bumps. But it is a whole other world doing the needed fab and welding and also the cost.

[KCaniglia]

You can also retrofit the IRS on the earlier cars. If you like, I have some parts, my friend did it to his MKII.

[svassh]

I did this several years ago on my MK2 certainly better for cornering but no difference in a straight line unless you count hard launches

[CraigS]

I forgot about hard launches. After years of living w/ axle hop, learning to drive around it, nailing the gas off the line was just wonderful. Both tires spun up and nothing else happened. After a while a quick little spin up was part of the fun on nearly every drive.

[mrmustang]

I really would like to know if his car feels & handles better since he did this upgrade.
While the IRS rides really nice, the 3-Link is the best option if you prefer drag racing over auto-crossing.
Also, my kidneys are great and Redbone's 60' times have improved since the change from Nitto 555's to NT-05's.

Coming in a few weeks late, but having not only done the upgrade to 3 link, but owned and tracked more than my fair share of various cobras (mostly FFR on the track, along with 1 contemporary and 2 ERA 289 FIAs), the upgrade from 4 link to 3 link gives you a better feel for the car past 4/10ths, also predictable handling while road racing and autocrossing. IRS, sure, a much different, more pliable feel on the street vs the solid axle rear, no matter if they are stock shocks, coil overs, 3 link with the better Koni shocks, or anything in between. Strictly street wise, the IRS is the rear suspension to have, on the track (only drag raced 1 cobra, that was an early FFR solid axle car with coil overs (2134K), well, it really depends on how hard you drive the car. The FFR with irs handled fantastic on the track, not as predictable above 7/10ths as the 3 link in my humble opinion, but more of a smooth ride coming out of the turns, on the throttle, if that makes sense.

Bill S.