apex gt4 brake duct install

[1MOREMOD]

going to try and start my brake duct install today. i have a few days off and thought it was time. not really looking forward to this one and hope it goes okay. put together a kit myself with the intention of having it split at the inner fender liner so i can run the front half from the bumper to fender liner in the winter and the second half will continue on to the backing plates for summer and track use only. parts include a pair of apex gt4 ducts, summit 3 inch high temp hose, summit 3 inch mounting plates, various clamps and fasteners and a 3 inch hole saw. im pretty unsure at this point if i can even make the 3 inch work passed the fender liner due to clearance. may have to reduce and run 2.5 from the fender liner to the backing plates. im sure i will have things apart and back together again dozens of times over the next few days.

[THE TECH]

It will be interesting for sure.

[mkPOTO]

subscribed

[1MOREMOD]

Well I didn't get very far. I got my car up in the air and layed out my plan of attack. Marked out the front lower undertray edge with a yellow grease pencil for reference when its off and seperated the front bumper skin from the undertray then I got the call. Had to go in to work for emergency coverage as another coworker had to take his wife to the ER. Looks like it will have to wait.

[datbimmerdoe]

damn, good shit!


*subscrib'd*

[1MOREMOD]

Little update. Ended up only working 3 hrs so came home and dug back in.
1. Marked undertray with grease pencil
2. Pull both inner and outer sections of undertray.
3. Mark undertray section to cut with hole saw and cut. Recommend a pilot hole even with it the hole saw wanted to walk and tear things up.
4. Slowly cut more material from the face of the undertray until the apex gt4 ducts will sit smoothly.
5. Mount the apex ducts along with section of hose and hose clamp. Used longer section of hose than I would need and cut to length later as I have lots maybe 10 feet from summit.
6. Pull front wheels.
7. Mark inner fender well with grease pencil using mounting bracket as template.
8. Drill pilot hole for hole saw and cut out inner fender holes.
9. Mount backing plate to inside of fender well.
10. Disassemble undertray for reinstallation.
11. Test fit, trim tray, test fit, trim some more, and trim hose length.
12. Attach hose to backing plate at fender well, then hang undertray over the top of it with the end sections removed and hose sticking out at that location.
13. I ran the hose between the cables that hang the undertray so remounting the cables is a challenge.
14. Attach hose to apex duct on one side and remount to inner portion of undertray then attach outer portion and repeat on other side.
15. Make adjustments to fit.
So far I'm at step 14 and have some pictures to post later. This was a big pita. Some troubles I had include the hole saw wanting to chew up the inner fender wall as its not flat and grabs. Routing of the ducts inside the tray. Mounting the backing plates to the inner fender well as its not flat and wants to stick out somewhat. Undertray reassembly and fit. It very close but in some sections sticks out or isn't perfect particularly around the apex ducts on the front and around the backing plates on the well. I'm thinking this might be as far as I go with this and not attempt to go all the way to the rotors. We will see.

[THE TECH]

Does it seem to be working out as you had hoped for so far?

[1MOREMOD]

yes for the most part. i would like the fit to be a little better and will have to mess around with it. planning on pulling the ducts from the front and installing clips like used on the rest of the undertray to retain the screws. i think overall it went well just a huge pain to do.

[THE TECH]

Originally Posted by chriszeh

yes for the most part. i would like the fit to be a little better and will have to mess around with it. planning on pulling the ducts from the front and installing clips like used on the rest of the undertray to retain the screws. i think overall it went well just a huge pain to do.

Well as long as you're happy in the end with the function of it.

[1MOREMOD]

here are the pictures i have so far.

[bigjae1976]

EDIT...found the answer.

Looks good so far!

[1MOREMOD]

well done deal. finished up this morning with a few more hours of fit and finish stuff. couple more notes. the drivers side has some hard lines for the cooling system that interfered with the placement of the duct hose to the inner fender liner so i zip tied it up a litte and out of the way. also the two bottom screws that hold the end section and middle section of the undertray together cant be used as they would go right into the duct hose and tear it. end product looks pretty stealth hardly noticeable especially this morning as its really foggy. my plan is to run it next season on the track like this with ferodo ds2500 pads and stock rotors and see if my temps run better and i dont melt pads and get fade. not gonna go all the way to the backing plates unless its needed. I do have parts for the complete system though if i decide to do the rest. it seems like the direction of the outlet in the fender liner points directly at the rotor when the wheels are straight or turned away and will hit the surface of the tire when turned towards.

[1MOREMOD]

heres the last of photos. will get more front when its clearer out and my car is clean. well guess my computer is acting up will post the rest another time.

[Grail05]

NICE JOB..... Chris, how much did this mod cost you? thinking of doing it myself.

[1MOREMOD]

the only expensive part was the apex ducts at 200 bucks. overall i probably spent 300-350 but i also have left over parts both the ducting hose probably 6 feet and 2 backing plate mounts that were 25 each, and several radiator clamps and mounting hardware. i initially bought enough to do all the way to the rotor backing plates and would have to come up with my own system there as well but dont know if i will do it now or not. dont think it will be needed as this should provide a lot of cooling i wasnt getting as is.

[1MOREMOD]

here are the other photos. one other thing the front end will be a real pita to take back apart if something else needs to be worked on. hoping i dont have to do that very often.

[xchosun1x]

when are you going tracking again? i'd love to hear some real world feedback review!

[1MOREMOD]

well wont be much use info wise until spring time. i do plan to go for a few winter lapping days in the next few months. next one would be novermber 6th. dont know what my temp was before unfortunatly. changing pads also which should be half the battle as i was melting the oems and getting crazy deposits.

[MaxL]

From the pictures it seems that the hose goes only to the wheel well, and not all the way to the backing plate - is that so? If so, why did you decide to do it this way vs. going all the way to the backing plates?

[xchosun1x]

Originally Posted by MaxL

From the pictures it seems that the hose goes only to the wheel well, and not all the way to the backing plate - is that so? If so, why did you decide to do it this way vs. going all the way to the backing plates?

+1

[1MOREMOD]

iTs addressed in this thread. My intention from the start was to create the system in 2 parts, from the undertray to the inner fender, and from the inner fender to the backing plates. If it was all one system my brakes would work like crap in the winter because couldn't generate any heat and I wouldn't stop. This way I can remove the second section for winter and non track use. I have the parts to complete the system but am going to run as is first and may not run the second half if it isn't needed.

[datbimmerdoe]

great work