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ShadowBolt
11-18-2007, 02:51 PM
As most of you know CMC 17 has been having brake booster problems. I am ready to change it. Eric said it's a bitch kitty (not like one of Mitch's pics) to change. I was thinking of cutting a hatch in the top of the dash. Is that legal and would it make it a lot easier than laying on the floor?


JJ

michaelmosty
11-18-2007, 04:09 PM
Jerry,
I wouldn't do any cutting to the dash. I think the main difficulty is the tight space under the hood.
I haven't touched mine since building it and it didn't have a motor in it at the time.

You will need to remove the strut tower brace (if installed) and possibly remove the upper intake. I think there were different sized boosters depending on the year and model.

Corey might have some good info. on this since he replaced his on night during an event. He used some cutting methods that you might not want to follow. :wink:

y5e06
11-18-2007, 06:45 PM
Corey might have some good info. on this since he replaced his on night during an event.

Believe he used a Cobra unit. Mustang guys can fill you in on the benefits. It might be a tighter fit. There was a lot of hammering and cussing at that time

Rob Liebbe
11-18-2007, 09:26 PM
Jerry,

I seem to remember that your car already has the larger Cobra style (or 94/95 GT or V6 booster) booster in it. You can compare the sizes at the local auto parts store, the difference is obvious side by side. Eric could possibly help confirm my memory. If that is the case then the hard work has already been done. Just remove the driver's seat and lay on the floor to get to the underdash stuff. Under the hood, you will need to remove a strut tower brace if there is one. If you still have the smaller original booster and want to install the larger booster, you will have to clearance the shock tower (I used a propane torch to soften the tower and a small sledge hammer to shape it) and relocate one of the four bolt holes that hold the booster to the firewall (this is achieved by slotting the one hole in the right direction).



Call me if you have any questions.

ShadowBolt
11-18-2007, 09:39 PM
Thanks for the help. The car does have the Cobra booster.


JJ

NASA13
11-18-2007, 10:52 PM
I love my cobra booster.
I just cut out the parts of the strut brace that were in the way and wallowed out the holes for the booster and used a sledge for the rest. Quick 2 hour cussing, headache, upside down ,good time.

ShadowBolt
11-26-2007, 06:44 PM
Any idea what year Cobra unit? Eric said he thought it was a 93 and it may be but I have a friend that owns an parts store and he looked this afternoon and the 93 Cobra unit is not in stock at any of the five Austin area warehouses! The 94-95 GT and V-6 unit is 7.125" dia. and the one I took off the car is 8.750" dia. Does anyone know for sure what year Cobra unit I need?


JJ

ShadowBolt
11-26-2007, 07:11 PM
The one I took off looks exactly like this one.
http://www.autopartswarehouse.com/details/QQFordQQMustangQQA1_CardoneQQBrake_BoosterQQ199419 95QQA15473150.html

Looks like it is a 94 95 but not cobra exclusive?


JJ

jeffburch
11-26-2007, 08:15 PM
www.rockauto.com

has a badass website for searching parts.

Click the big red start button in the middle of the page.

jb

ShadowBolt
11-26-2007, 09:07 PM
www.rockauto.com

has a badass website for searching parts.

Click the big red start button in the middle of the page.

jb


Thanks Jeff.
Been there, done that. I used to buy their Raybestos brake rotors for the C6......$19.00 each for directional vaned!
I still need to know what year? 93 and 94 are diferent part numbers but the pics look the same on the web sites.


JJ

marshall_mosty
11-27-2007, 08:32 AM
Jerry,
Go with the 94-95 booster. The booster will fit the pedals and the M/C's are interchangeable up to 98'ish.

Don't know why the PN's are different, but you shouldn't see that big of a differance (if any). Might just be Ford (or Rock Auto's) PN scheme to get more money for a "special" part (93 Cobra).

Rob Liebbe
11-27-2007, 09:17 AM
Jerry,

The 93 Cobra Booster is different than the 94-95 GT. The "boost" may be the same but the mounting hole pattern IS different. If you can find a 93 Cobra booster, that will simplify your installation. However, the 93 booster is hard to find and expensive where the 94-95 booster is less expensive and readily available. You will only have to slot one of the four mounting holes and maybe celarance the strut tower to make the 94-95 unit work and then you will have an easier time if you ever need a replacement.

RichardP
11-27-2007, 10:06 AM
I've never quite understood why people want to fight with the physically larger boosters? I'm still using the original booster that came on my car from the factory 16 years ago. Works just fine.

I'm guessing it bolted right up but since I've never unbolted it, I don't really know... :)


Richard P.

ShadowBolt
11-27-2007, 10:13 AM
Thanks guys!

Richard,

I'm just replacing a defective unit with what I have been told is the hot set-up. The old one was a larger unit so the mods have already been done.

JJ

jeffburch
11-27-2007, 10:32 AM
Why do these boosters fail so often?
:idea: FoMoCo? :P
:idea: Poor vacuum? :twisted:

jb

ShadowBolt
11-27-2007, 10:37 AM
I read that if your fuel system is too rich the gas fumes will eat the booster up. They sell (and I have seen them on a few stock vehicles) a in-line filter that removes the fuel before it gets to the booster.


Jerry

RichardP
11-27-2007, 11:01 AM
I'm just replacing a defective unit with what I have been told is the hot set-up.


Yea, I'm just curious why people think the larger stuff is the "hot set-up" especially for a "race car." I think the stock stuff is a bit over boosted (although not nearly as over boosted as the stock steering).

I guess it's good if your wife needs to go to the grocery store but on the track a harder pedal is a more stable platform for heel and toe.

Is it just because it says "Cobra" on it that people think that it must be a special "performance improved" part???

I drove the car with the stock booster disconnected and while that was a bit more effort than I wanted it didn't take much to get used to. I think Chris liked it better that way?

Daron and Mason's new AI car did away with the booster all together...


Richard P.

michaelmosty
11-27-2007, 12:15 PM
FWIW, I have the stock booster off of a 91 GT and it still works great.

marshall_mosty
11-27-2007, 12:28 PM
I too have a stock booster that I bought used off E-bay. I'm eventually going to go with the delete kit from MM, just need to figure out when I'm going to do so.

AI#97
11-27-2007, 12:57 PM
Stock Million pound hydro boost here! Love the firm but easy feel. Doubt I will ever go to anything different mostly because I can get these parts for cheap at any parts store in the event of failure. Tilton pedals are sort of hard to come by in a pinch unless you buy two full sets! :lol:

Todd Covini
11-27-2007, 10:23 PM
I put hard metal plates on my clutch, brake and gas pedals. They all feel hard now. 8)

Todd Covini
11-27-2007, 10:25 PM
....except there was this one time.... :shock:

Adam Ginsberg
11-27-2007, 10:50 PM
At band camp.....