mk4 brake upgrade onto the mk3
 

I have recently rebuilt all of my mk3's calipers and they work great whith the new rotors and pads. When ever i do break test the ABS works great. Now i know when your close to locking up your wheels its the most break pressure your gona get, now my question is my mk3 has ABS and performes great but im going to use much more sticky and wider tires for autocross events. The facotry set up works great on the but in a race setting i belive they will fade and quickly, i have a local tuneing shop that will put on mk4 claipers onto my car for dirt cheap, my question is will there be a problem whith the ABS whith the mk4's callipers on my mk3 and if so what would i have to do to make them work since i dont want to drop 1k into my breaks for a brake kit

LOL, "dirt cheap" and "custom MKIV break swap".... Have some details for us? We might have to make these guys famous.

You may have some issues with the ABS system but I don't know how bad any symptoms would really be. The front wheels are still monitored independently, the rears are monitored as a unit and the computer is still in place to ensure that they keep rolling as needed. All that I can imagine is that the system might function too aggressively.

I would be more concerned about making absolutely sure that all 4 wheels are upgraded properly to maintain the appropriate bias... Trying to leave the rears stock and screwing with proportioning valves isn't going to cut it.

Personally, I'd install some braided brake lines, upgrade the brake fluid and install a larger 4Runner master cylinder and see how that feels for a while. You may need the 4Runner master cylinder with the MKIV calipers anyway.

Th reson I can get them cheap is because he's got a few mk4 calipers lying around. Also since my friend is droping 10k into his solara at his shop he is keeping the labor costs way down( personally I think he's just trying to keep us happy and spending but the upgrade is all ill be buying from him). I have my friend whith his 3000gt that has run into this ABS problem constantly when doing upgrades of this nature and I'm wondering if the mk3 would be prone to the same issue. P.S he is only doing the brakes them self. so only the calipers and the mounts nothing more