# Upgrading only front brakes.



## zaid90 (Feb 12, 2012)

would there be any major issues when upgrading an mk4 jetta front brakes from the 11.3" to 12.3 rotors, the ones found on the GTI and keeping the 9.1" solid rear rotors? the GTI has 10.1" vented rear but my jetta has 9.1" solid rear. 

info on rotor size can be found here: http://forums.vwvortex.com/showthread.php?1782231


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## Thy_Harrowing (Dec 7, 2014)

zaid90 said:


> would there be any major issues when upgrading an mk4 jetta front brakes from the 11.3" to 12.3 rotors, the ones found on the GTI and keeping the 9.1" solid rear rotors? the GTI has 10.1" vented rear but my jetta has 9.1" solid rear.
> 
> info on rotor size can be found here: http://forums.vwvortex.com/showthread.php?1782231


Not really as long as the caliper fits the larger rotor (if it doesn't you'd need to get the matching calipers from the GTI) and also that you could throw off the braking bias as it were from the factory. I'm pretty sure I got into the subject of brake bias with a dude in the following thread I'm going to link you to. So I don't have to repeat myself you can just read in there about what brake bias/balance is and what the ramifications. This is something to consider anytime one is making brake upgrade. Some brake kits that are specifically designed around a certain models weight distribution and other factors can keep a good brake bias by careful choice caliper piston size and many other factors but then your average brake upgrade isn't a carefully designed kit so there are no guarantees that proper bias is maintained. Nevertheless, it's pretty hard to throw the brake bias off enough that it's gonna be a problem. At the end of the day it's your decision what you choose to do. I'm just giving you the info.

http://forums.vwvortex.com/showthread.php?8819306-Let-s-talk-brakes


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## belly232 (Mar 27, 2005)

If you are just upgrading the rotors there is no issue other than making sure the caliper will fit over the larger rotor. If you are using larger caliper as well, just make sure you bleed them properly and you will be fine. If you are going with larger caliper the front brakes will be doing a lot more work than the originals and the rears will do less unless you upgrade the rears as well.


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## slow_key (May 26, 2004)

if you have a 1.8T /VR6 the swap is easy tdi/2.0 is almost as easy
VR6/1.8T you have 288mm brakes 312mm is just a caliper bracket away
for the 2.0/TDI brakes you have 280mm brakes you will need the spindle from a vr6/1.8T plus caliper and carrier
I did this on my TDI jetta wagon HUGE differance


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