Fox T-Bird/Cougar Forums

Technical => Suspension/Steering => Topic started by: gumby on May 19, 2007, 10:33:38 PM

Title: brake plumbing, SN95 master, etc.
Post by: gumby on May 19, 2007, 10:33:38 PM
went to one of my favorite stores today, EARLS. happens to be in the same lot as my work even :hick:
got some fittings to match the new master cylinder, some short lines, and a couple "tee"s. also gave them the lengths i need for my new rear lines. they should be ready monday or tuesday along with the adj. prop valve that they were out of stock on. weird cause they usually have like 20 of them on the shelf.

3-2 conversion, gumby style
(http://i25.photobucket.com/albums/c73/gmby23/87%20turbocoupe/714f1d24.jpg)
(http://i25.photobucket.com/albums/c73/gmby23/87%20turbocoupe/97276e26.jpg)

the rear line there is jus hangin out waitin for the prop valve. i will probly bend it 90* to point straight up, but didnt wanna do that till im holdin the prop valve in my hand to be sure of its orientation.

and in the rear
(http://i25.photobucket.com/albums/c73/gmby23/87%20turbocoupe/bb91a445.jpg)
sweet 7/16x24 to -3an fitting with the groove in it to match the retaining clip on the factory bracket!
w/a -3an "tee" to connect the braided lines i will run out to each caliper. also grabbed a couple banjo fittings and bolts to fit the IRS calipers

fully assembled the IRS today as well(hopefully for the last time). its sittin on a roll cart waitin on the rear lines to arrive.

its been a good saturday :evilgrin:
Title: brake plumbing, SN95 master, etc.
Post by: 32VFoxBird on May 19, 2007, 10:41:27 PM
so you bypassed the factory prop valve completely, hmmm.
Title: brake plumbing, SN95 master, etc.
Post by: gumby on May 19, 2007, 10:43:35 PM
bypassed? i think its in the trash can in the garage, lol

ill be runnin a wilwood adjustable on the rear line as soon as it shows up.
Title: brake plumbing, SN95 master, etc.
Post by: Prototype Services on May 20, 2007, 01:56:31 AM
Looks good. I did my brakes the same way before I went with the Tilton 3 pedal set-up. The lines even then are the same, just have two masters for the brakes rather than a double stock-type.
I would suggest you avoid aluminum fittings in the brakelines though. If it were me, I would replace that rear Tee with a steel or better stainless version.
Title: brake plumbing, SN95 master, etc.
Post by: Tbird232ci on May 20, 2007, 07:38:21 AM
I love Earls stuff.
Title: brake plumbing, SN95 master, etc.
Post by: gumby on May 20, 2007, 09:36:53 AM
Quote from: Prototype Services;148449

I would suggest you avoid aluminum fittings in the brakelines though.

whats the reasoning behind this?
Title: brake plumbing, SN95 master, etc.
Post by: dudeman351 on May 20, 2007, 10:05:42 AM
yes what is the reasioning? the only issue i can see is possibly corossion but if you keep your fluid fresh it shouldn't be a problem. as for structually i don't see aluminium being an issue.
Title: brake plumbing, SN95 master, etc.
Post by: 1BadBird on May 20, 2007, 11:58:20 AM
Looking good there Gumby :D 
Did that place make the lines for you??  I had checked into factory lines for my IRS and !!! they are expensive!! one place I went to even said they weren't available (the flex lines) stock calipers were close too $200 with a $60 or 65 core!!(each!!) Although I found some other Cobra calipers. 



John
Title: brake plumbing, SN95 master, etc.
Post by: gumby on May 20, 2007, 01:48:38 PM
yeah, they keep certain lengths in stock, but can make any length you need.
Title: brake plumbing, SN95 master, etc.
Post by: 1BadBird on May 20, 2007, 10:17:45 PM
gumby, are you going to run the flex lines from that blue tee fitting to the calipers or ?? won't they be a little on the long side?? When I get back to working on my beasty, let me know how much the short lines were and, if you would please, get me what I need after I send you the $$$  I already have an adj b/p valve. I will also need to run a new line to the rear of the car.
Title: brake plumbing, SN95 master, etc.
Post by: gumby on May 20, 2007, 10:49:22 PM
yes, im gonna run braided all the way from the tee to the calipers. i dont foresee any issues. guess we will find out.

you can find a dealer local to you also
http://www.holley.com/index.asp?division=Earls

i dont know the prices yet, i put them on the shops account, hehe
Title: brake plumbing, SN95 master, etc.
Post by: Prototype Services on May 20, 2007, 11:27:02 PM
Sorry to take so long to reply
The reason for not using aluminum on brake fittings is fatigue, not so much corrosion. Brakes have 1000-1500psi each time you apply the brakes. Every part tries to swell like a balloon, but only a tiny amount. Aluminum will only take a certain number of cycles before it cracks. Maybe it will never happen to you, but why risk a $10 part? Especially with the flex line moving up and down attached to it. Now you have the bending fatigue added in.
I know some sanctioning bodies don't allow aluminum in brake lines.
One more thing, it is best to keep flex lines as short as possible to keep a firmer pedal. You may never notice on the street, especially on the rear brakes. But flex lines will "balloon" more than a tubular steel line.
Racing motorcycles use a -2 line and I think F-1 does too. Nextel Cup and every other modern racecar I have seen uses -3. They got away from using -4 lines to keep the area of the tubing smaller to reduce the ballooning affect. This keeps a firmer pedal/lever.
But as I said, on the street you may never notice.
Dave
Title: brake plumbing, SN95 master, etc.
Post by: gumby on May 21, 2007, 06:21:01 AM
thank you for the information. i wouldnt have thought about fatigue from internal pressure on the fittings.
all the braided lines on my car are -3. i figure even with a relatively long run(36") its gonna be better than the rubber flex line combined with rubber lines at the calipers on a live axle w/discs.
i keep a very close eye on all my brakin components. im gonna run it this way now(braided lines), and see how it works. ive driven full cars plumbed with braided. doesnt make it "right," i know, but it also didnt have any pedal feel or line failure issues.
ill ask ricky today if he has a steel tee to swap with that aluminum one or not.
Title: brake plumbing, SN95 master, etc.
Post by: Prototype Services on May 21, 2007, 07:30:04 AM
It will be safer with the steel Tee. Yes, all braided lines will work, but it isn't "best".
As I said, I eventually changed my Sport over to a triple master cylinder set-up and full manual brakes. I was roadracing the car as well as daily-driving and I was VERY concerned with pedal feel and firmness.
Dave
Title: brake plumbing, SN95 master, etc.
Post by: 1BadBird on May 21, 2007, 09:31:16 AM
Prototype Sevices, If one doesn't use flexable braided stainless line, what else is there to use then?? The OEM rubber lines swells alot more than the stainless. I too will be running my car in NASA'S HPDE class. I also will be changing my brakes to manual for the same reason. I'm used to manual brakes so to drive it as a daily driver doesn't bother me.

gumby, thanks for the site, I'll check it out. :D

John.
Title: brake plumbing, SN95 master, etc.
Post by: Chuck W on May 21, 2007, 09:39:02 AM
I think gumby was talking about plumbing the rear brakes entirely in flex from the T.  PS was suggesting hardline over to near the caliper and then a shorter length of flex.
Title: brake plumbing, SN95 master, etc.
Post by: gumby on May 21, 2007, 12:29:29 PM
correct.
if you want to run hard line and shorter braided lines near the caliper, jus grab an IF tee instead of the AN tee i have. run some 3/16 hard lines over to the frame rails and back behind the axle centerline. then run the braided from there.
Title: brake plumbing, SN95 master, etc.
Post by: Prototype Services on May 21, 2007, 04:36:40 PM
Just use the shortest amount of braided teflon -3 line as possible. Obviously you have to run it from the frame to the front calipers like the stock rubber, and ideal is a piece from the rear frame/body to the axle housing, hard lines out to calipers and then short braided to the floating calipers. My calipers were rigid mounted Wilwoods.
Some Tee the hardline to both sides of the body/frame and then run a single piece of braided to each caliper, much like the front is done.
I was glad to see someone eliminate the stock prop valve.
Title: brake plumbing, SN95 master, etc.
Post by: gumby on May 21, 2007, 05:50:36 PM
Quote from: Prototype Services;148788
Some Tee the hardline to both sides of the body/frame and then run a single piece of braided to each caliper, much like the front is done.
1badbird and i are both runnin cobra IRS units. that is the reason for this style setup on our cars.
Quote from: Prototype Services;148788
I was glad to see someone eliminate the stock prop valve.
by the time i would have made the factory prop usable the way i intended, it was more a manifold than a prop valve. i didnt see much use for an extra manifold
Title: brake plumbing, SN95 master, etc.
Post by: Prototype Services on May 22, 2007, 03:00:04 AM
I'm surprised the guys at cornercarvers didn't explain about the aluminum yet.
Email me sometime, we can chat about roadracing.
Dave Dellinger
Title: brake plumbing, SN95 master, etc.
Post by: gumby on May 22, 2007, 06:28:02 AM
eh, im still new over there. they may not like me yet :flame:

:D
Title: brake plumbing, SN95 master, etc.
Post by: Prototype Services on May 22, 2007, 02:30:51 PM
Me too. I tend to browse and read and rarely post. Just like here.:hick:
Just don't ask anything about Nextel Cup suspensions.
I suddenly got toasty warm.....:flame:
D2
Title: brake plumbing, SN95 master, etc.
Post by: gumby on May 22, 2007, 06:30:22 PM
no steel version of that tee is available. my other option was to add three more adapters and use a brass block. i chose to stick with the aluminum tee.

i did pick up my prop valve while i was there. man this thing is tiny!
(http://i25.photobucket.com/albums/c73/gmby23/87%20turbocoupe/0d7bd033.jpg)
(http://i25.photobucket.com/albums/c73/gmby23/87%20turbocoupe/5fdfc52f.jpg)

ill add a couple more pics after i plumb it in. im still waitin on one 12mm to -3an adapter to get the master/prop plumbin finished up.
Title: brake plumbing, SN95 master, etc.
Post by: 1BadBird on May 22, 2007, 08:03:25 PM
Man that's tiny compared to mine. Can I join the chat about road racing?????
Title: brake plumbing, SN95 master, etc.
Post by: Prototype Services on May 22, 2007, 09:51:19 PM
Sure.
Start a new thread somewhere, and we can all swap stories and tell lies.:D
Just hope we don't get flamed by dragracers, streetracers, and guys afraid to go over 100mph because they're scared or worried about gas mileage. :flame:
Dave
Title: brake plumbing, SN95 master, etc.
Post by: Prototype Services on May 22, 2007, 09:54:32 PM
"Man that's tiny compared to mine."

Genetics? Ha!

Yeah, I wonder about that PV.
But they have been getting smaller.
I liked my Kelsey-Hayes and had it mounted to the tower.
As long as it works and will hold a setting.

Use the aluminum if you have to, but keep an eye on it. Did you check Aeroquip? Goodridge? Look at CVProducts and see if they have it in steel.
D2
Title: brake plumbing, SN95 master, etc.
Post by: gumby on May 22, 2007, 10:11:24 PM
i will check those places as well. goodrich is also local to me, thats where my 12mm to -3an adapter is comin from.
i expected a prop similar to 32Vfoxbird's. i about ped myself when he set this one on the counter today. there is no good shot of the set screw to lock it down, but you can kinda see the side of it in the second pic on the right of the .


got the rear tee and lines placed, and clear of the IRS carrier tonight. IRS is in. i am a happy camper :banana:
Title: brake plumbing, SN95 master, etc.
Post by: gumby on May 22, 2007, 10:25:23 PM
Quote from: Prototype Services;149094

Start a new thread somewhere, and we can all swap stories and tell lies.:D

done.
http://www.foxtbirdcougarforums.com/showthread.php?t=14035

:evilgrin:
Title: brake plumbing, SN95 master, etc.
Post by: gumby on May 30, 2007, 08:25:14 PM
a'ight, got my 12mm fitting today. heres the final plumbin layout.

(http://i25.photobucket.com/albums/c73/gmby23/87%20turbocoupe/83853ca5.jpg)
(http://i25.photobucket.com/albums/c73/gmby23/87%20turbocoupe/a45bad31.jpg)

ill secure the lines as soon as i know where everything is gonna set with the motor in place and everything, but this should be pretty close to it.


:birdsmily:
Title: brake plumbing, SN95 master, etc.
Post by: Chuck W on May 30, 2007, 08:47:17 PM
Wow..that is a tiny prop valve.  I have one of the Wilwood ones I'll be using in the '80....and it's gigantic compared to that.
Title: brake plumbing, SN95 master, etc.
Post by: JeremyB on May 30, 2007, 09:58:41 PM
So, any real tech behind not using aluminum brake fittings? I understand that Al doesn't have a fatigue limit, but that doesn't mean it can't be used in this application.
Title: brake plumbing, SN95 master, etc.
Post by: Prototype Services on May 30, 2007, 11:58:46 PM
Try asking Wilwood, Brembo, Tilton, or ask CVProducts or even Aeroquip or Goodridge. They can give you the scientific explanation.
D2
Title: brake plumbing, SN95 master, etc.
Post by: JeremyB on May 31, 2007, 12:20:09 AM
To the best of my knowledge, Earl's and Aeroquip both sell Al fitting without any warnings saying not to use them in high pressure hydraulic service.

Do they?

I understand the scientific reasoning behind why one might want to be wary of Al in high-stress applications, but it (along with many other materials without fatigue limits) are used as such in commercial applications.

What material are the steel pieces made out of 1018, 4130? Is the Al 3003, 6061, 7075?
Title: brake plumbing, SN95 master, etc.
Post by: gumby on May 31, 2007, 04:14:26 PM
i dunno. im not a metallurgist. are you?

if you want the physics equations of how much each pedal push will expand the fitting, how many expansions/contractions the fittin can handle before it will explode, and metallurgy of various hydraulic fittings, look em up on CC.

im in the buisness, and talked about this with many who have been in longer than i have. i also dug around for a while on CC, and found what i needed. dave merely pointed out the disadvantage of the aluminum fitting, and recommended a steel alternative.
Title: brake plumbing, SN95 master, etc.
Post by: JeremyB on June 01, 2007, 12:36:57 AM
I understand metallurgy, which is why I question the reason for not using Al fittings unless you are worried about corrosion.

I think there is a big myth about Aluminum's lack of a fatigue strength. Notice the two charts below. The first is for steel, the second for various kinds of Aluminum.

(http://www.griffshp.com/belchja/forums/steelfatigue.jpg)

(http://www.griffshp.com/belchja/forums/aluminumfatigue.jpg)

The fatigue strength for steels is ~50% of the ultimate strength.
Aluminum has no corresponding fatigue strength, although the strength at 10^8 is sometimes used. At 10^8, the "fatigue strength" from the charted metals is ~25-30%.

1018 (mild steel) has an ultimate strength of 64ksi (kilopounds per square inch), and a fatigue strength of 32ksi
4130 (chromoly) has an ultimate strength of 97ksi and a fatigue strength of 49 ksi
6061-T6 has an ultimate strength of 45ksi and and equivalent fatigue strength of ~11ksi
7075-T6 has an ultimate strength of 82ksi and and equivalent fatigue strength of 21ksi


Best case pure fatigue scenario for 7075 Al is that is has ~65% of the strength of mild steel after 100 million cycles. Not very good, but that is where the confusion begins. I don't know the average cyclical stress a fitting receives. I couldn't figure it out even if I knew the pressure from the hydraulic fittings - I would need an FEA program to figure out the stresses. Plus, what vehicle is going to see 100,000,000 panic stops? Zero. Zilch. Nada. As the number of cycles decreases, the performance of aluminum increases. At some point, 1018 and 7075 cross. The real hard part of the question is - are the Al and Steel parts designed the same? Are they the same part, or is the Al thicker.

So, you end up with a problem that is essentially unsolvable using back of the envelope methods. Thus, I would lean towards an empirical answer.

How many aluminum fittings have failed in hydraulic service? None that I know of.
Sounds like a poor way to solve a problem, but sometimes experience is the best proof.
Title: brake plumbing, SN95 master, etc.
Post by: 1BadBird on June 02, 2007, 08:00:22 PM
I'm in no way a metallurgist (sp?) but I was in the Air Force although I only flew on C-130s as a radio operator. Every part that I could see where hydraulics run, was aluminum. Do they use a different type of aluminum? I know that's probably a stupid question but..............Just wondering why all the fuss about that fitting. 

John
Title: brake plumbing, SN95 master, etc.
Post by: Prototype Services on June 03, 2007, 09:18:38 PM
No fuss, use what you want.
Title: brake plumbing, SN95 master, etc.
Post by: blu84302 on June 03, 2007, 10:42:57 PM
Back brakes only run around 100 psi.  I doubt that the fitting would fail. 

Have you guys ever used solder to fix a brake line?  Works great!