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jdogg
OK, so I've had my car for almost 6 years now, and it has been through a LOT of changes over those years...It started as a stock class 2.0 AXer, then to street prepared, the to SM2 with the addition of the -6. I had done a smattering of track events over those years, primarily focusing on AX, but last fall the track bug bit and bit hard!! I've done about 8 of 'em since October last year, and just can't get enough.
But this brings me to my question(s)/issues. As my driving is improving, I find I am being much harder on the car (a good thing), but some issues are coming to light, most notably the brakes.
I have the much hyped 914club billet hubs on my car, utilizing M calipers, SC vented (not cross drilled) rotors, Carbotech XP10 racing pads, brand new 19mm MC, etc. The brakes work very well...once the pads get some heat in them they will stick your eyeballs to the windshield with no fade issues. The issue I am having with this set up is the pedal softening and the travel growing after a couple sessions. At first I suspected the MC, so I replaced it...then after bleeding the system and leaving it under pressure with my power bleeder, I noticed some fluid seepage around the RF caliper. The calipers were rebuilt last fall and have about 8 track weekends on them, but I went and got a new rebuild kit and rebuilt it. I thought that maybe that was a potential source of air and a possible reason for the pedal travel issues.
I spent the past weekend at Carolina Motorsports Park (CMP) in lovely east bumfuck middle of nowhere no cell service one stoplight Kershaw, SC. A very challenging layout, tight and technical, and very hard on equipment with a lot of hard braking zones, so I figured it was the perfect venue to test out my brand new MC and freshly rebuilt caliper and see if I could keep a pedal all day long. After session 2 on Saturday the pedal travel had indeed moved again. So I bled the brakes (heel and toe with a low brake pedal is nearly impossible) and the pedal came right back where it needed to be. I resigned myself to the fact that I was just going to have to bleed 'em every two sessions. Well, it was successful, uneventful rest of the weekend with plenty of bleeding (although it was hot, really fucking hot...103 on Sunday with lots of humidity). Fast forward to Monday night when I go to unload the car from the trailer....no brakes!!! WTF?!?!
Seem I have blown the left front caliper out now too, and this one leaked fluid all over the damn place....

So does everyone need to bleed their brakes that often to keep a firm - high pedal? Is rebuilding calipers every 2 or 3 events whether they need it or not going to need to become a regular maintenance item? Is there a better way?
914forme
Not an issue I am aware of, you got other issues, find them.

Couple of thoughts or ideas, seems you listed you front brakes while they are the highest used items in braking, the rears do have function otherwise we would not have them and save weight. Are you sure your rears are doing anything or at least the proper amount of braking?

Have you checked the calpier temps? Have you checked for run out on hte rotors? Have you checked you hard and softlines?

I run many a auto-x events and never had to rebuld the calipers. Crewed a PCA J-class racer never rebuilt the calipers there either. But if you are overheating them, even though you don't notice fluid boiling, you could be higher than you think. Temp paint or strips are a wise investment to help track down possible problems.

My beat is you ar over using your fronts, heating them to the point of rubber degragation and feeling the pain. I would add a insulator beween the the pads and the piston, help keep the seals alive a little longer. And then add rear bias to help easy the burdent a little.

Depending on how they are setup the rears might not be producing enough heat to allow the pads to build working temperature, and function properly. One trick I use in clases that did not allow bias adjustments was to run different compounds front and rear. Works better than you think.
drew365
I have a similar brake setup to yours. Yes a soft pedal is a recurring problem. Yes I bleed them after every event and sometimes during the event. No, I haven't had a problem with blowing out calipers.
ptb
What brake fluid are you using and do you have any air ducting to cool the brakes? On my '87 911 (fat pig at 2,800 lbs) I can cook the brakes at a high brake track like Gingerman but be ok at Mid-Ohio. I use Motul 600 with Porterfiled P-4 pads and have 993 ducts mounted to my front A-arms. The biggest improvement was getting rid of the Super Blue brake fluid and using Motul 600. The next step would be Castrol SPX at $80/quart
Dave_Darling
I think you mean SRF?

There is a recent discussion on the Bird's racing board by 911 guys about this. Consensus seems to be: Put heat-resistant shims (someone mentioned Titanium??) between the pad and caliper. Switch to SRF. Duct air to the rotors. And even then, you may have to rebuild the brakes annually...

--DD
jhadler
You mention a lot of the setup you have, but nothing about fluid. Make sure you've got GOOD fluid in there. All of the best brake gear in the world isn't gonna last if you're using poor brake fluid. And no, not all brake fluid is the same.

Shims. Yeah, a set of shims between the pad and the caliper piston will also help. Some say titanium, but they're probably trying to sell them to you. The difference in thermal conductivity between Titanium and Stainless Steel is pretty small, but the cost difference is HUGE. Have some SS shims made if you really want to go that route.

Also, brake ducts. Brake ducts. Brake ducts. Brake ducts. No one thing you can do will help improve brake longevity at the track than installing brake ducts. Do it.

You may also want to look into properly bleeding the proportioning valve too, as that tends to catch air in the system.

Brake Fluid.... Here's writeup we put on our region Time Trials website about brakes and brake fluid. I think you'll find it pretty thorough and helpful.

http://www.sccatimetrials.org/requirements/brakes.html

-Josh2
jdogg
Ok, the question of brake fluid has come up several times...I use ATE Super Blue, and it is always fesh before every event (its GOTTA be fresh as often as I am bleeding 'em, haha!).

Also- no proportioning valve..replaced with a Tee at the -6 conversion. Rear venting clearance set properly also. The car feels very well balanced under threshold braking.

My airdam has ducts molded into it for brake cooling, but I have yet to find suitable hose to run to the calipers. Suggestions?

I'd love to hear from someone else with the mystical 914club billet hub set-up...the clearance from the edge of the rotors to the caliper is very minimal, to the point that there is evidence of occasional rubbing...I suppose that could also be a source of additional heat build-up...Is a regular brake lathe capable of turning down the diameter of the rotor i.e. 13" dia. to 12-7/8" dia.?

These shims that have been alluded to....who makes 'em? Just how thick are they? Is there enough room to stuff them in as well as a brand new fat assed racing brake pad?
jhadler
ATE is good, Motul is better, SRF is great.

Brake ducting... Just go to Home Depot and get some flexible dryer hose and some hose clamps and zip ties. Anything you can do to get more air to the brakes will be better than nothing. Ideally, you'd want some nice high temp hose (like you get from racer shops etc.). And, ideally you want to put the air where it'll be the most effective, into the caliper. But honestly, any air is better than no air at all. You'd be surprised how effective it'll be. Just aim the air at the caliper and/or rotor.

If you want to invest in some good mounts for the ducting, take a look at the brake duct mounts that Chris (Tangerine Racing) sells. Pretty nice, and simple too.

As for shims? I wouldn't go that route until you've exhausted all your other options. They're really going to have a pretty low cost/benefit ratio. Yes, they help, but nowhere near as much as ducting will.

-Josh2
mudfoot76
+2 on switching to Motul and adding brake ducts.

I was having fade issues on my car during DEs and was looking into fabbing up ducts. Then someone suggested that I lessen my CSOB quotient and try the Motul. Night and day difference. No more fading, even on the hottest of days and I am pushing the car to the fullest (I have the M calipers on front too). I've held back on adding ducts as I don't have the problem anymore.
jdogg
Thanks for all the great input and suggestions!!! beerchug.gif

I now have a plan of attack for my next event (not till Sept. 22 VIR-s & VIR-f)

1- rebuild that puking caliper
2- head to the home depot for hose and rig up some sort of cooling deal
3- increase the rotor to caliper clearance ever so slightly
4-Try the bitch out! driving.gif
I just bought 2 new freakin' cans of ATE SUper Blue, so the CSOB in me has me holding off on the Motul 600 for right now, but if that fucker goes soft on me at the track, I may just have to spring for it.

I'll try to remember to post back the results.

Also-
CMP is VERY tough on brakes, any deficiencies you may have will INDEED show up there...I know some folks who refuse to go to that track for that very reason. It is a GREAT 914 track, not too many loooooooooooong straight-aways, and lots of tight stuff!!
jhadler
QUOTE(jdogg @ Aug 10 2007, 11:13 AM) *

CMP is VERY tough on brakes, any deficiencies you may have will INDEED show up there...I know some folks who refuse to go to that track for that very reason. It is a GREAT 914 track, not too many loooooooooooong straight-aways, and lots of tight stuff!!


Sounds just like our departed Second Creek Raceway. Lot's of transition, more than a couple heavy braking zones, and not a lot of time between them. That, coupled with the altitude makes it a very hard track for brakes. Good fluid and good coolingwill go a long way...

-Josh2
914forme
SS Shims, and add some heat sync coumpund to them on the pad side. Or pad compound copper ceramic SS ceramic then ceramic and piston. You want to have fun add a computer style heat sync out the top. As long as you have wheel clearance. You coud add water cooling by shooting water mist at then. You could use the computer heat syncs that are water cooled also.

The J-class racer ran Mid-Ohio, Putnam, IRP, and a few other Robeling Road and Elkhart. All stock, except good fluid, and Ducts on the front. Never had issue, though a stock 2.0L can only push you so fast so the braking zone for others was non existant for us. The front brake coolers where a piece of al pipe with a mount that fit over the rotor with a small air foil built in. I shoud have painted a coke logo onto it cause it looked very simular to a Coke/beer can.

The area you are in, look at your Nascar builders for cheap take offs, those guys need to cool brakes way more than you do. And the hand me downs are cheap!!!!!
jhadler
QUOTE(914forme @ Aug 10 2007, 11:50 AM) *

SS Shims, and add some heat sync coumpund to them on the pad side.


blink.gif blink.gif blink.gif

The shims are to reduce the heat transfer, not improve it... The last thing you want to do is add some kind of thermally conductive paste to the system...

QUOTE
You coud add water cooling by shooting water mist at then.


And don't forget to replace your rotors after every race as they will be hideously warped at the end of the day. biggrin.gif

Still, it'd be really cool to make water cooled brakes like the European truck racers do. The front of the car would spout steam every time at the end of the straightaway. Really freak out the competition...

-Josh2


914forme
Yes I did say that wrong. Unless he is the compition then I said it just right happy11.gif
Eric_Shea
Might want to look for the late model pistons (dished) and remove your knock-back pins. Much more surface area for cooling.
jdogg
QUOTE(Eric_Shea @ Aug 12 2007, 11:35 PM) *

Might want to look for the late model pistons (dished) and remove your knock-back pins. Much more surface area for cooling.



Eric-
Tell me more...By late model, do you mean late model "m" caliper pistons? How would I know what the hell I was looking at? Are the SC pistons the same size? What are the "knock back pins" ? Do you mean the pins in the caliper that slide into the piston?
Eric_Shea
Late model M-Caliper pistons (kinda harder to find in M-Calipers but some had them) or A-Caliper pistons. Yup, they're the same size.

Knock-back pins are the ones that slide into the pistons. By 76 or 77 (I think) ATE had done away with them and went with the later dish or cup style pistons in the same calipers. Knock-back pins are meant to literally knock the pad back toward the rotor offering a high pedal feel. They have been known to be problematic in race cars and many simply remove them or their recepticals.

If you stay with your current pistons and you're racing, you may want to simply remove the mechanism inside the piston (C clip and yank). If you go with the later cup pistons simply snap the pins off with a pair of needle nose pliers.

One thing I've noticed that hasn't been touched on is the rubbing issue. This is a "Bozo No-No" That's what is cooking your calipers. No, a standard brake lathe will not do it, they're meant to do the sides not the edges. You should find a machine shop with a large enough lathe and mill about 2mm off for clearance. I would also have the rotor cryo'd before or after that so you're not always milling rotors.

Do that... get some ducting in there and you'll be a happy camper racer.
davep
Cryo'd rotors would be a good idea. The rotor should not be larger in diameter than where the pads touch them (it adds excess weight, and worse increases the inertia).

Possibly part of your problem is not cooling the brakes properly before parking. Cool down laps on the track or off of the track are necessary to get the heat out of the brakes. If you do not do so, a hot rotor will warp, and also cook the piston seals. I have seen dust seals that are totally disintegrated. They probably should not be used. If you use a brake duct to get air into the center of the rotor, then at least use metal ducting; I understand that the vinyl ducting is not even legal for most clothes driers. Second, consider a fan setup to force air through after you park it to ensure an even cool down; I'm not suggesting to build it in, just a little rig to blow air into the scoops. I strongly believe that more damage is done while parked than when on the track.

I have it on good authority (from an endurance racer) that oversize master cylinders are very useful in preventing low pedals. Part of that comes from the pistons being knocked back excessively by the rotor ( thermal expansion, wobble, warp, flex, whatever). He used a 23 mm (back in 1971 to 1973), standard on the GT was the 20mm MC. Also, brace the MC to reduce the floor flex. He never had problems with the "S" or 908 caliper variant.
alpha434
You can buy titanium sheet in 99% pure form and make those shims just as easy as the SS. And about as cheap. I've been going to the Denver Art Museum and stealing their construction slag (those fools are using titanium sheet to cover the whole building.)

I see it go up on ebay every so often too.

The problem with shims- and more so with the Ti over stainless, is the way it rattles. It pushes the pads apart a little extra and you lose brake pressure. Bad for coming down the straight and late braking that first turn...

But if you affix the Ti to the brake pad, it doesn't cause a problem. I bend a piece around the pads and through the split in the pads and back up. Works so good, that I run them on my stock 914 on the street.
alpha434
I've been doing the water cooled brakes for a while. And I've got a great mechanism, but I need some better electronics. . .

In each wheel, I have a unit, made from a small piece of PVC tube, with a C02 quick change adapter (paintball gear) on one side, and a tube running to a windshield squirter off of some odd year acura integra. That model had a valve that was part of the squirter. I run the wires to the brake pedal. If you hit the brakes, it squirts.

The problem is that I don't want it to squirt EVERY time. Pretty much just when you late brake hard. So I need to add a g-force sensor into the loop or something. If it squirts every time, then you run out of water way too fast.

In the picture in my avatar, the unit is just behind the headlight cover, and you can refill it/change co2 cartridges by removing the black piece.
jdogg
QUOTE(Eric_Shea @ Aug 13 2007, 11:24 AM) *

One thing I've noticed that hasn't been touched on is the rubbing issue. This is a "Bozo No-No" That's what is cooking your calipers. No, a standard brake lathe will not do it, they're meant to do the sides not the edges. You should find a machine shop with a large enough lathe and mill about 2mm off for clearance. I would also have the rotor cryo'd before or after that so you're not always milling rotors.



Bozo NoNo? Ha, tell me I'm stupid why don't you, haha! I like that.... av-943.gif Anyway, on that topic, what do you think about machining the caliper for clearance instead of the rotors...with the track pads I'm running, I expect to be replacing rotors annually, if not more. Would 2 MM be too much to take out of the spacer/caliper?
Is 2mm enough?

Or maybe I should just say F-it and go with a late model carrera setup....hmmmm, $$$$$$
davep
I think 2mm would get you into the bores for the bolts.
Besides, when are the pads with respect to the edge of the rotor?
If the rotor is way outside the pads enough to hit the caliper, then that is too much. You turn the rotor and save: unsprung weight, significant inertia and clearance. That inertia reduces acceleration (robs horsepower) and requires extra braking to scrub off (extra heat in the rotor).
Eric_Shea
QUOTE
Bozo NoNo? Ha, tell me I'm stupid why don't you, haha! I like that....


Maybe it's a Midwest thing. Maybe I'm too old. Nobody remembers the "Bozo the Clown" show? And if the kids did anything bad then old Bozo would call them on it saying "That's a Bozo No-No"...??? Nevermind. Suffice to say I wasn't calling you stupid. wink.gif Here's a link to more info than you would possibly want:

http://www.snopes.com/radiotv/tv/bozo.asp

I agree with the Canuck. 2mm would put you into the bolt bores. Get those puppies to stop rubbing and you'll stop most if not all your problems.

If you replace annually then you may not want to cryo. Turning the edge off them shouldn't be more than $40 bucks per year...
jdogg
Thanks, guys! I have a plan!
Eddie914
Are you overheating the front brakes or the rear brakes?

My 914-6 3.2 is set up with 911 SC brakes, Porterfield R4 pads, ATE Superblue fluid and a manual proportioning valve in place of the stock proportioning valve.

Many on the board indicated that the stock proportioning valve can be eliminated. With the manual proportioning valve set wide open, rear lock-up was quite easy to invoke. I continued to increase the brake bias to the front until rear lock-up was eliminated then added an additional turn to the adjustment knob for a safety margin.

The last couple of events the pedal has softened during the day. When the front brakes were bled, the soft pedal continued. When the REAR brakes were bled the nice hard pedal returned???? What gives? Don't the front brakes always overheat first?

At the last event I used an infrared heat gun (I know ... it's not the best type of instrument to measure temperatures on shiny metal) to compare the front and rear brake temperatures after a track session (followed by a cool down lap). Guess what? The rear brakes were MUCH hotter than the front brakes! 550 degress versus 275 degrees.

The front brake cooling ducts must be working pretty well.

Now it's time to fabricate rear cooling ducts.

Anyone have any ideas for rear ducting?

Eddie
davep
Using an IR gun is okay as long as you treat the values as low, and use them for comparative purposes. It sounds like you have your brakes pretty well sorted out. Ducting air to the center of the rotor would likely be the best route, but difficult; the vented rotor acts like a radial fan. I have seen clam-shell devices that duct air into the rotor from the outside.
Brando
I second the motion for more cooling - on all 4 wheels. Definitely add some phenolic material between the pads and pistons. What kind of flex lines are you using?

There was a member on one of the pelican or rennlist boards I think who took is brake-dust shields and fabricated ducts into those. It was very cleanly done from aluminum and looked nice. It blew right into the center of the rotor and used 1½" or 2" flex hose from the front valence. Come to think, it was a 944 because it had the brake ducts going through a euro-style bumper with ducts in the fog light holes.
Eddie914
Here is a nice setup for rear brake cooling ducts.

IPB Image

Eddie
914forme
Nice setup for a 944, 911, VW beatle, Thing, or Ghia! You have to make you own for a 914. The other problem is hte wheel size you are using, 15"s do not leave a lot of room back there. But a simple scoop might be all you need. Use an old dust shield, dril a couple holes, and ad a few pieces of sheet metal to see how it all works out. Or why not use a different set of wheels that have a been designed to pull air through the opening.

Other issues with rear ducts, you need a cover over your inlet, or else you pickup rubber, and gravel all day long, and they don't mix well with brakes either. This is one of the reasons the Boxster lost the lower intake ducts that where on the prototype, sucked too many foreign objects into the intake system.

Another thing to note on the above picture, the brake bolts have no provision for locking. Now maybe he used lock-tite GREEN! buts I doubt it. You hang around motorcycle, Kart, and aviation folks a lot, you learn we auto-racers take a lazy approach to bolting and securing stuff.
alpha434
BBS still sells wheel fans, I know of no other company that still does. It was a 80's fad that was somehow forgotten. Those bastards.

Anyway, you could also probably make some, and your front wheels would benefit as well as the rears. Or have them made. Plus they have an aero-advantage, albeit small. Search for pictures of the Shell 962. It had them. I also saw that a german 914 setup for racing had them. It was the picture with 30 914s or however many on one car trailer. * old picture, if anyone remembers the post...

The wheel fans act centrifugally to suck air out from under the body and past the brakes.
914forme
Yep, I have seen 80s vettes use Corvair fans in the wheels with welded adapters.

Don't the turbo twists have a fan function also???? I could be wrong on that.

Or do it like NASCAR and just toss tones of duct work at it.
jdogg
OK...quick update..I had the rotors cut down at the machine shop, and rebuilt the offending caliper. The next move is ducting some air down there, which brings up this question.....Where to send the air. Is it best to aim it at the center of the rotor(at the hub) and let it radiate out the venting, or should it be directed right at the caliper? It appears from Eddie's picture that sending it to the center of the rotor is the deal, and is the direction I am leaning....Opinions???


I do believe the seal failure was indeed caused by excessive heat...the dust seals were completely toast, and the piston seals felt a little hardened when I removed them..Hopefully these latest changes will cure my braking ails, will know for sure in about 2 weeks.

Also- Thanks out to Eric Shea for sending me some much needed pieces....I am sure he has much better things to do with his time than send me o-rings, bolts and a rear adjuster, but he came through as if it were nothing!
race914
You want to cool the rotors.

Several vendors offer cooling 'kits' similar to this pic

Click to view attachment

or you can go with the 'clam shell' approach

Click to view attachment
Eric_Shea
Glad to help! wink.gif

For your situation... go with the AJ kit pictured above. Or - Try an event with what you've done. A rotor rubbing on a caliper will kill it in short order. I'd be willing to bet you're good to go now.
jdogg
I am going to rig something up similar to that AJ kit RACE914 posted above...my spoiler has ducts in it already, I just need to run some hose and direct the air to the proper place....I may dig out my splash shields that were removed long ago to see if there is a neat way use those to duct some air in there...
DanT
Ran 2 days at Laguna Seca this weekend and had absolutely no brake problems.
M calipers with vented rotors up front with Porterfield Rs4 pads.
Front 914-4 calipers in rear with stock pads. No proportioning valve, just a T.

no fade, good pedal feel for 20-30 min sessions on Friday.

Saturday was Cherry's Jubilee. We give hot laps to hot rodders for charity.

3 hard laps, come into hot grid, unload one rider and get another, for another 3 hot laps. This is very hard on the brakes, since you never get to do a cool down lap, and the brakes begin to heat sink after several rounds.

again no problems with fade or pedal feel.
I have just a stock style LE front air dam. No additional brake cooling.

I would bet your brake heating is/was due to your dragging caliper/rotor. smile.gif
Joe Ricard
I had a lapping day with an LE air dam. no problems with Stock solid front rotors. R4 pads.

Next event with cow catcher air dam I smoked the brakes to a pretty blue.

Air flow is EVERYTING.
DanT
QUOTE(Joe Ricard @ Sep 10 2007, 10:34 AM) *

I had a lapping day with an LE air dam. no problems with Stock solid front rotors. R4 pads.

Next event with cow catcher air dam I smoked the brakes to a pretty blue.

Air flow is EVERYTING.

yes, on my 2.7L RS motored 914-6 I had a GT style air dam and had to make sure the ducting was hooked up to cool the 4 piston JFZ calipers.
jhadler
QUOTE(Dan (Almaden Valley) @ Sep 10 2007, 06:21 PM) *

yes, on my 2.7L RS motored 914-6 I had a GT style air dam and had to make sure the ducting was hooked up to cool the 4 piston JFZ calipers.


Dan, how and where did you setup the oil cooler with that air dam. I have one, still on the shelf , and could not find a cooler that would fit in that opening.

-Josh2
DanT
QUOTE(jhadler @ Sep 10 2007, 09:53 PM) *

QUOTE(Dan (Almaden Valley) @ Sep 10 2007, 06:21 PM) *

yes, on my 2.7L RS motored 914-6 I had a GT style air dam and had to make sure the ducting was hooked up to cool the 4 piston JFZ calipers.


Dan, how and where did you setup the oil cooler with that air dam. I have one, still on the shelf , and could not find a cooler that would fit in that opening.

-Josh2

Josh,
it was a 19 row Mocal, I don't remember the details though, since it was about 11 years ago.
worked great, never had a heat problem even with big motor. All stainless lines all the way front to back with aeroquip fittings, used a carrera thermostat mounted in the rear near the motor.
If I remember correctly the cooler was mounted to the air dam...I can do some checking on that and get back to you.
grantsfo
I use SC rotors with BMW 320 i calipers in front and SC rotors in back with SC calipers. No ventilation at all. However I have BBS wheels that do a good job of keeping things cool. No fade in longer track sessions. But I dont have much car to slow down. I was having some issues with front rear balance, but I think it was pad issue. I just put new set of Hawk Blues on the front and balance appears to be much better.
914forme
Th AJ pieces will work wonders up front, the rears you will still have to build your own. At least I don't know anybody who does them. Fiberglass would be easiy for this. Make a plug out of foam, wrap in foil, lay up your part. Remove foam plug via a destruction method of your choice bond it to the old backing plate. Open up plate for airflow.

Crude design follow.
jdogg
QUOTE(914forme @ Sep 11 2007, 12:27 PM) *

Th AJ pieces will work wonders up front, the rears you will still have to build your own. At least I don't know anybody who does them. Fiberglass would be easiy for this. Make a plug out of foam, wrap in foil, lay up your part. Remove foam plug via a destruction method of your choice bond it to the old backing plate. Open up plate for airflow.

Crude design follow.



Where would you grab the fresh air from? A scoop under the car similar to the AJ kit? NACA duct in the quarter panel?
914forme
I would NACA the rocker with a screen.
jdogg
Click to view attachmentClick to view attachmentClick to view attachment[attachmentid=127
840]Update....I finished the brake ducting last night. I dug out the splash shields that I had taken off years ago and started sawzall-smiley.gif and welder.gif and came up with this:
jdogg
Going to VIR this weekend to test it all out.. Saturday and Sunday on South Course, and Monday on full....3 days of abuse!! I think it is going to be good!!!!
Eric_Shea
Get screens on there... you will pickup marbles.

Brant, calling Brant.

Very nice engineering BTW. What size steel for the tubing?
jdogg
QUOTE(Eric_Shea @ Sep 20 2007, 10:51 AM) *

Get screens on there... you will pickup marbles.

Brant, calling Brant.

Very nice engineering BTW. What size steel for the tubing?




Yep, I am going to figure out something for the screening tonight...don't need to plug those vents with melted rubber and negate the system!


The hose size is 2-1/2" which was dictated by the duct openings molded into the airdam. I used 2-1/2" exhaust tubing that I ovalled out at the splash shield...It was actually a pretty simple project once I examined all the clearance issues and found the best place to run the hose into.I have not road tested it yet, but it appears there should be no clearance/binding issues with suspension movement and with steering..the shields required a little "massaging" once the rotor was on for clearance, so they don't look as pretty now, haha!
Joe Ricard
I've been thinking about this a lot. I am fairly sure I will end up ripping something like that off if I hit a cone or have an off road excursion on a track.

I am thinking of running the tube through the inner fender well just above the control arm. Use the fog light grills as the inlet. and then do something like Jdogg did for mounting it to the spindle.
jdogg
Joe-
I looked at running it above the arm as well, but short of looping the hose up to the top of the fender and back down to the hub, I couldn't see a way to keep it out of the tire's way at full steering lock.
I've temporarily retired from dodging cones, so I'm not worried about one of them getting under there....but an off road excursion, especially over the gaiters, could indeed inflict some damage...That's why I bought twice as much hose as I needed.....Spares!!
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