GTI PP 340mm front brake conversion on a 4Motion GSW.

[APEXWheels]

Hey all,

I spend most of my time here answering questions and providing recommendations for wheel and tire fitments, so I was hoping to cash-in on some of that good karma to potentially get some help and insight to a few questions of my own.

The topic in question is brakes. More specifically, installing OEM MK7 GTI PP front brakes on a 2017 4-Motion Golf Sportwagen. I have been researching this topic for the last couple of weeks and I have been struggling to find a straight answer as to what will be required for the conversion, and if 4-motion vs non-4-motion makes any differences to said requirements. I've seen a lot of conflicting answers, so I was hoping someone who has done this mod before can chime in with some clarity.

Long story short, my OEM F&R brakes are practically toast and I recently acquired a relatively fresh set of take-off calipers from a PP GTI. Since the car needs brakes anyways. I figured I would upgrade the fronts while I'm at it. Basically, my goal is to is install the front GTI calipers with 340mm rotors and pads, while keeping the OEM rears and just replacing the rotors/pads with factory sizes.

The main question I need clarity on is: What will be required to fit the GTI calipers up front, aside from the basics (rotors, pads, etc)?

I am almost certain I will need new/larger dust shields, but I am unsure if I will need GTI knuckles as well. This is where the concern of 4-motion vs. non-4-motion also comes into play, as I am unsure if there are any part differences. Aside from that, will I need to make any changes to the brake booster or lines taking into consideration I will be keeping the factory rear brakes?

Any help is greatly appreciated!

-Geirsen

 

[Rollux]

From what I understand you need to know if your strut tube diameter is 50mm or 55mm. If it is 55mm you have the same knuckles as the GTi and the calliper bolts on.
if you have 50mm struts, you will need to change them for 55mm versions, and new knuckles and wheel bearings.

 

[Q-Bert]

Pretty sure all you need are the carriers and dust shields from the PP brakes. I believe the hub and wheel bearing in both the 50mm and 55mm knuckles are the same PT#.
I don't think you need the knuckles at all.

 

[manu97]

Hey Geirsen,

https://www.golfmk7.com/forums/inde...nt-caliper-option.353249/page-14#post-7878031

I know this is for the TTS conversion - but that's marketed as a direct bolt on for the GTI/R. @camerone has a 4mo GSW I'm pretty sure, and those bolted right up for him. Hope this helps!

 

[tigeo]

They bolt on, that's really it. Direct swap. Your cast iron knuckles work fine and you just re-use the mounting bolts as they are the correct length for the knuckles; the ones from a car with aluminum knuckles (R/GTI/AT) are too long. No need for anything beyond the calipers/carriers and if you want, new 340mm dust shields. Many GSW/AT folks run these. No need for any other OBD changes etc. It's really that simple and so many have done it.

 

[tigeo]

Pretty sure all you need are the carriers and dust shields from the PP brakes. I believe the hub and wheel bearing in both the 50mm and 55mm knuckles are the same PT#.
I don't think you need the knuckles at all.

They are not the same - bearings on the 55s are larger.

 

[tigeo]

From what I understand you need to know if your strut tube diameter is 50mm or 55mm. If it is 55mm you have the same knuckles as the GTi and the calliper bolts on.
if you have 50mm struts, you will need to change them for 55mm versions, and new knuckles and wheel bearings.

There is no need to change knuckles here...the brakes are direct bolt-on.

 

[miikez.]

I upgraded the master cylinder to a Golf R master cylinder when I switched over to Golf R brakes. Kept the same brake booster.

 

[tigeo]

I upgraded the master cylinder to a Golf R master cylinder when I switched over to Golf R brakes. Kept the same brake booster.

Lots of debate about If that is necessary...most folks don't and have no issues. I'm running a 6 pot 350BBK (APR) and pedal feel is great.

 

[miikez.]

Lots of debate about If that is necessary...most folks don't and have no issues. I'm running a 6 pot 350BBK (APR) and pedal feel is great.

Yeah I just went with it since it was a cheap part and easy swap.

 

[APEXWheels]

Thank you all for the insight, very helpful in clearing things up!

They bolt on, that's really it. Direct swap. Your cast iron knuckles work fine and you just re-use the mounting bolts as they are the correct length for the knuckles; the ones from a car with aluminum knuckles (R/GTI/AT) are too long. No need for anything beyond the calipers/carriers and if you want, new 340mm dust shields. Many GSW/AT folks run these. No need for any other OBD changes etc. It's really that simple and so many have done it.

There is no need to change knuckles here...the brakes are direct bolt-on.

Would you say there is any particular benefit with running the GTI knuckles? I might be able to get a set of take-offs for free but if they aren't required for the brake swap and there aren't any added benefits, I likely won't bother with them.

-Geirsen

 

[tigeo]

Thank you all for the insight, very helpful in clearing things up!





Would you say there is any particular benefit with running the GTI knuckles? I might be able to get a set of take-offs for free but if they aren't required for the brake swap and there aren't any added benefits, I likely won't bother with them.

-Geirsen

The only one would be having access to 55mm struts/coilovers. If I was going through the trouble, I'd source Club Sport knuckles to gain some delicous negative camber. I don't know many that have bothered - plenty of good 50mm strut and coilover options. Aluminum knuckles are a bit lighter so one other thing.

 

[crxgator]

You could buy 50-55mm strut collars to use the aluminum knuckles as well.

 

[camerone]

I'm late but i did the TTS calipers swap on my 4Mo GSW as Manu said and yeah they'll bolt right up assuming you have the caliper carriers (which you should, it would be a bit strange to just get the caliper haha). All the other info here lines up with my experience so you should be good to go. It's a relatively straightforward job IMO. If you're gonna bleed your brakes anyway (which you are), you could look into doing stainless steel lines at the same time while you're at it...