Cobra booster installed !@#$

Steel1

Mustang Master
Aug 18, 2017
1,419
694
143
Connecticut
Had some time today so fired up the heater in the garage and started my Cobra brake booster install.
Back story, last winter I upgraded to 4 lug rear disc and master cylinder but decided to try it with the stock booster, pedal was too hard for my liking
so unfortunately I knew what I needed to do.

I know changing a heater core on these cars is commonly know as the number one pain in the !@# , imo installing a Cobra booster on a car with engine, harnesses
etc. intact has to be a top 3 pain in the !@#!! Probably didn't help that the engine in my car is a 351w based stroker with taller deck height.

I will admit I am not great a documenting things because I kind of get into a zone when I'm working on cars and forget to take pics along the way.
But if anyone is curious here's a brief description with some pics of my process and a few pics attached.
Things I needed to remove :
Lower steering wheel cover
Knee bolster
Knee bolster reinforcement
Removed master cylinder and mounting bracket rotated forward / down. Surprisingly you can move it quite a bit saved me from bleeding brakes again thanks @Mustang5L5
Dipstick and had to bens tube out of the way ( probably 393w issue )
Unplugged large harness connection by drivers strut tower to give me slack to pull it up out of the way
Various vac hoses
Firewall clutch adjuster, had to screw it all the toward firewall
Drivers valve cover
Clutch cable bracket

Old booster was pretty easy to remove , pushed drivers seat all the way back and it's a pretty straight shot to upper nuts for booster using a combo of extensions and deep 3/4"
socket, lower nuts are easy to get to as well as removing clip etc. on pedal stud. Removing knee bolster is key to getting to the upper mounting nuts.

Fitting the Cobra booster was a lesson in patience to say the least !
I had the booster in and out probably 8-10 times with multiple flogging sessions between my 3lb sledge and strut tower. I know people have said they've gotten this booster in without massaging strut tower but there was no way around it for me.
I would get booster a little closer every time then mark strut tower , pull out booster , flog tower , reinstall and so on.
Took me about 5hrs. by myself for removal and install , still need to reinstall drivers valve cover but I want to touch it up first since it got a few nicks during the process.
Anyways here's some pics , I did measure pushrod length using MM instructions prior to install.
0124211132.jpg

0124211132a.jpg

0124211229.jpg

0124211227.jpg

0124211624.jpg

0124211633.jpg
 
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I was totally ready for the type of drawn out, life decision questioning battle you just described when I did mine. I cut down the studs on the booster just a little bit, went right in. No BFH, no hating my life. At least there. Getting those nuts on the studs under the dash, God have mercy. I felt like a T-Rex with my arms bent like that under there.

Did you cut your studs at all?
 
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Either cut the studs down or elongate the holes closest to the engine and it will slip right in. I have done the booster swap in under an hour start to finish. No banging strut towers, very little swearing.
 
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Had some time today so fired up the heater in the garage and started my Cobra brake booster install.
Back story, last winter I upgraded to 4 lug rear disc and master cylinder but decided to try it with the stock booster, pedal was too hard for my liking
so unfortunately I knew what I needed to do.

I know changing a heater core on these cars is commonly know as the number one pain in the !@# , imo installing a Cobra booster on a car with engine, harnesses
etc. intact has to be a top 3 pain in the !@#!! Probably didn't help that the engine in my car is a 351w based stroker with taller deck height.

I will admit I am not great a documenting things because I kind of get into a zone when I'm working on cars and forget to take pics along the way.
But if anyone is curious here's a brief description with some pics of my process and a few pics attached.
Things I needed to remove :
Lower steering wheel cover
Knee bolster
Knee bolster reinforcement
Removed master cylinder and mounting bracket rotated forward / down. Surprisingly you can move it quite a bit saved me from bleeding brakes again thanks @Mustang5L5
Dipstick and had to bens tube out of the way ( probably 393w issue )
Unplugged large harness connection by drivers strut tower to give me slack to pull it up out of the way
Various vac hoses
Firewall clutch adjuster, had to screw it all the toward firewall
Drivers valve cover
Clutch cable bracket

Old booster was pretty easy to remove , pushed drivers seat all the way back and it's a pretty straight shot to upper nuts for booster using a combo of extensions and deep 3/4"
socket, lower nuts are easy to get to as well as removing clip etc. on pedal stud. Removing knee bolster is key to getting to the upper mounting nuts.

Fitting the Cobra booster was a lesson in patience to say the least !
I had the booster in and out probably 8-10 times with multiple flogging sessions between my 3lb sledge and strut tower. I know people have said they've gotten this booster in without massaging strut tower but there was no way around it for me.
I would get booster a little closer every time then mark strut tower , pull out booster , flog tower , reinstall and so on.
Took me about 5hrs. by myself for removal and install , still need to reinstall drivers valve cover but I want to touch it up first since it got a few nicks during the process.
Anyways here's some pics , I did measure pushrod length using MM instructions prior to install.
0124211132.jpg

0124211132a.jpg

0124211229.jpg

0124211227.jpg

0124211624.jpg

0124211633.jpg
You used the Cardone 5473155?
 
I was totally ready for the type of drawn out, life decision questioning battle you just described when I did mine. I cut down the studs on the booster just a little bit, went right in. No BFH, no hating my life. At least there. Getting those nuts on the studs under the dash, God have mercy. I felt like a T-Rex with my arms bent like that under there.

Did you cut your studs at all?
Didn't cut studs but I did elongate the upper let hole slightly until my dremel broke.
 
Either cut the studs down or elongate the holes closest to the engine and it will slip right in. I have done the booster swap in under an hour start to finish. No banging strut towers, very little swearing.
Yeah I didn't cut studs but did elongate upper left hole a bit, I'm still thinking having the taller deck height of a 393w may have played
into it.
 
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This was the first big task I did alone, swapping to the cobra booster and 5 lug. Had no idea wtf I was doin, asking help on here every 30 minutes, looking on you tube etc. I’ve seen some guys say they finished their swap in like a day or so. It took me a week or more lol, but I did it and it was a learning experience, I was also swapping out all the suspension at the same time, plus redoing the rear end. I remember my wife came in bc I was yelling, she said are you ok I thought you said it was gonna be fun? I yelled f*#% yeah it’s a blast, then heard the garage door shut and there was nice whiskey drink waiting for me lol!!
 
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Just curious...I did the 4-lug rear disc conversion on my '86, along with '87-'93 front spindles and calipers, all with the stock '86 master cylinder. The pedal was quite hard and I didn't like it. Members of this forum (Mustang5L5?) suggested a larger bore diameter master cylinder, and I put an '85 Lincoln MC on it with the stock booster and I got really good pedal feel.
 
Just curious...I did the 4-lug rear disc conversion on my '86, along with '87-'93 front spindles and calipers, all with the stock '86 master cylinder. The pedal was quite hard and I didn't like it. Members of this forum (Mustang5L5?) suggested a larger bore diameter master cylinder, and I put an '85 Lincoln MC on it with the stock booster and I got really good pedal feel.
I tried leaving the stock booster and just upgrading the m/c but pedal was too hard for me so had to bite the bullet and upgrade the booster.
Seems like it's hit or miss , some people get away with the stock booster maybe just a matter of preference.
 
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Had some time today so fired up the heater in the garage and started my Cobra brake booster install.
Back story, last winter I upgraded to 4 lug rear disc and master cylinder but decided to try it with the stock booster, pedal was too hard for my liking
so unfortunately I knew what I needed to do.

I know changing a heater core on these cars is commonly know as the number one pain in the !@# , imo installing a Cobra booster on a car with engine, harnesses
etc. intact has to be a top 3 pain in the !@#!! Probably didn't help that the engine in my car is a 351w based stroker with taller deck height.

I will admit I am not great a documenting things because I kind of get into a zone when I'm working on cars and forget to take pics along the way.
But if anyone is curious here's a brief description with some pics of my process and a few pics attached.
Things I needed to remove :
Lower steering wheel cover
Knee bolster
Knee bolster reinforcement
Removed master cylinder and mounting bracket rotated forward / down. Surprisingly you can move it quite a bit saved me from bleeding brakes again thanks @Mustang5L5
Dipstick and had to bens tube out of the way ( probably 393w issue )
Unplugged large harness connection by drivers strut tower to give me slack to pull it up out of the way
Various vac hoses
Firewall clutch adjuster, had to screw it all the toward firewall
Drivers valve cover
Clutch cable bracket

Old booster was pretty easy to remove , pushed drivers seat all the way back and it's a pretty straight shot to upper nuts for booster using a combo of extensions and deep 3/4"
socket, lower nuts are easy to get to as well as removing clip etc. on pedal stud. Removing knee bolster is key to getting to the upper mounting nuts.

Fitting the Cobra booster was a lesson in patience to say the least !
I had the booster in and out probably 8-10 times with multiple flogging sessions between my 3lb sledge and strut tower. I know people have said they've gotten this booster in without massaging strut tower but there was no way around it for me.
I would get booster a little closer every time then mark strut tower , pull out booster , flog tower , reinstall and so on.
Took me about 5hrs. by myself for removal and install , still need to reinstall drivers valve cover but I want to touch it up first since it got a few nicks during the process.
Anyways here's some pics , I did measure pushrod length using MM instructions prior to install.
0124211132.jpg

0124211132a.jpg

0124211229.jpg

0124211227.jpg

0124211624.jpg

0124211633.jpg
The pic of the interior pieces that were removed helped me a ton, thanks! Got it out tonight, swapping out steering shaft while I have the room. Trying to not let scope creep get to me on the wiring, I'd like to drive this thing before the summer is over...
 
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Either cut the studs down or elongate the holes closest to the engine and it will slip right in. I have done the booster swap in under an hour start to finish. No banging strut towers, very little swearing.
Either cut the studs down or elongate the holes closest to the engine and it will slip right in. I have done the booster swap in under an hour start to finish. No banging strut towers, very little swearing.
I am getting ready to do this project just curious how much did you cut off or do you know the finished length.