Hydroboost mounting question
Thread Starter
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Joined: Dec 2007
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From: Hartselle AL
St. Jude Donor '09
Hydroboost mounting question
Am in the middle of converting to the hydrodboost & Borgensen box and am wanting to install studs in the firewall for the hydroboost instead of through bolts. Have seen some pictures here where this has been done, just want to check the size of the studs. The vacuum booster studs are 3/8" 16. The firewall holes are 7/16". Does a 3/8" stud "gripper" fill a 7/16" hole?
Thanks in advance.
P.S. Am glad the removing the vacuum booster is behind me, that is the absolute worse job on a C3.
Thanks in advance.
P.S. Am glad the removing the vacuum booster is behind me, that is the absolute worse job on a C3.
Thread Starter
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From: Hartselle AL
St. Jude Donor '09
Bump...
Am really not looking forward to the idea of having to do the upside down contortionist exercise to mount the hydroboost like the vacuum booster was mounted.
Am really not looking forward to the idea of having to do the upside down contortionist exercise to mount the hydroboost like the vacuum booster was mounted.
Thread Starter
Race Director
Joined: Dec 2007
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From: Hartselle AL
St. Jude Donor '09
Thanks for the response and suggestion.
Pro
Joined: Dec 2004
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From: Fairfield CT
Race Director
Joined: Mar 2006
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From: Florida
You can just fab a u shaped plate out of sheet metal with the proper bolt pattern from the booster mount as a template and tack weld the head of regular bolts to it. Or you can make a couple of flat plates if that's easier.
Thread Starter
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From: Hartselle AL
St. Jude Donor '09
The goal is to find the right sized serrated bolt, fish them through the holes then pull them tight/secure them via nuts. Basically, just the reverse set up from the back of the booster but with the studs pointing into the engine bay.
Thanks.
Instructor
Joined: May 2004
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From: houston tx
i used the serrated bolts from an astrovan, i believe they are metric, 13mm. they grabbed nice and tight and i didnt have to hold them back behind the firewall. i just tugged on them sideways with the dental floss till i got the nuts (and lockwashers) on them.
i never ever want to have to go back up and get those F%^#ing bolts out again!!!
i also have hydroboost and the borgeson and i highly recommend them to anyone who wants to enjoy driving the car, made a huge difference.
i never ever want to have to go back up and get those F%^#ing bolts out again!!!
i also have hydroboost and the borgeson and i highly recommend them to anyone who wants to enjoy driving the car, made a huge difference.
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Thread Starter
Race Director
Joined: Dec 2007
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From: Hartselle AL
St. Jude Donor '09
i used the serrated bolts from an astrovan, i believe they are metric, 13mm. they grabbed nice and tight and i didnt have to hold them back behind the firewall. i just tugged on them sideways with the dental floss till i got the nuts (and lockwashers) on them.
i never ever want to have to go back up and get those F%^#ing bolts out again!!!
i also have hydroboost and the borgeson and i highly recommend them to anyone who wants to enjoy driving the car, made a huge difference.
i never ever want to have to go back up and get those F%^#ing bolts out again!!!
i also have hydroboost and the borgeson and i highly recommend them to anyone who wants to enjoy driving the car, made a huge difference.
)That's exactly the info I was looking for and for the same reasons. Am assuming that you just removed the bolts from the Astro hydroboost back plate and reused them?
Thanks a bunch.
Drifting
Joined: Jul 2002
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From: The only Corvettes in Highett Victoria
Another way.
BTAL,
I've just done this, but I've had to pull the Hydroboost out again. I stripped the thread on the HB low pressure return line fitting, and I'm having trouble finding the right fitting here in Melbourne. I know it's a 5/16" x 24 thread, but getting one with an AN -6 on the other end is the problem.
However, pulling the HB out is easy. When I'd pulled the old vacuum booster out, I went to the extra trouble of pulling out the pedal assembly. I then TIG welded captive nuts on the inside of the hanger bracket, 3/8" UNC. Then I just used 3/8" UNC bolts from the engine side of the firewall. Easy peasy. Makes it easy to remove the HB again if you need to, like I just did.
I also have the Borgeson box, but I removed the factory pump and took out the return line nipple. I brazed in a steel AN -6 male fitting in the stock location for the Borgeson return, then brazed in another male -6 AN for the HB return line. So all of my lines have AN fittings at each end. Cost a bit, but I'm not going to have to worry about it again.
I know you said you can't weld at home, but if you take the pedal hanger assembly to a local weldor, he will be able to do it for you.
Regards from Down Under.
aussiejohn
I've just done this, but I've had to pull the Hydroboost out again. I stripped the thread on the HB low pressure return line fitting, and I'm having trouble finding the right fitting here in Melbourne. I know it's a 5/16" x 24 thread, but getting one with an AN -6 on the other end is the problem.
However, pulling the HB out is easy. When I'd pulled the old vacuum booster out, I went to the extra trouble of pulling out the pedal assembly. I then TIG welded captive nuts on the inside of the hanger bracket, 3/8" UNC. Then I just used 3/8" UNC bolts from the engine side of the firewall. Easy peasy. Makes it easy to remove the HB again if you need to, like I just did.
I also have the Borgeson box, but I removed the factory pump and took out the return line nipple. I brazed in a steel AN -6 male fitting in the stock location for the Borgeson return, then brazed in another male -6 AN for the HB return line. So all of my lines have AN fittings at each end. Cost a bit, but I'm not going to have to worry about it again.
I know you said you can't weld at home, but if you take the pedal hanger assembly to a local weldor, he will be able to do it for you.
Regards from Down Under.
aussiejohn
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From: Scottsdale Arizona
Instructor
Joined: Oct 2009
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From: Lakefield Ontario
Aussie John
Do you have a picture showing where you brazed in the return lines on the power steering tank?
Did you use a brass fitting?
Seems that a lot of us are doing the hydro boost upgrade, along with either a R & P, or steering box!
I like the idea of using the 13mm studs from an Astro Van H/B, and driving them in from underneath the pedal assembley, truly an evil job getting too that upper left nut, at times I thought I was going to loose mine!
My thanks to everyone who has written about this conversion,it sure has helped make things clear in my mind!
Do you have a picture showing where you brazed in the return lines on the power steering tank?
Did you use a brass fitting?
Seems that a lot of us are doing the hydro boost upgrade, along with either a R & P, or steering box!
I like the idea of using the 13mm studs from an Astro Van H/B, and driving them in from underneath the pedal assembley, truly an evil job getting too that upper left nut, at times I thought I was going to loose mine!
My thanks to everyone who has written about this conversion,it sure has helped make things clear in my mind!
Drifting
Joined: Jul 2002
Posts: 1,944
Likes: 20
From: The only Corvettes in Highett Victoria
Hydratech part #9101
Pretty sure, just look up Hydratech and go to the Hoses and fittings link, scan almost to the bottom and there it is. 5/16"-24 O-ring Male to AN -6 Male 5/8 Hex Size, $21.95. Make sure you read the caveat re overtightening.
Regards from Down Under.
aussiejohn
Drifting
Joined: Jul 2002
Posts: 1,944
Likes: 20
From: The only Corvettes in Highett Victoria
Yes, somewhere.
Aussie John
Do you have a picture showing where you brazed in the return lines on the power steering tank?
Did you use a brass fitting?
Seems that a lot of us are doing the hydro boost upgrade, along with either a R & P, or steering box!
I like the idea of using the 13mm studs from an Astro Van H/B, and driving them in from underneath the pedal assembley, truly an evil job getting too that upper left nut, at times I thought I was going to loose mine!
My thanks to everyone who has written about this conversion,it sure has helped make things clear in my mind!
Do you have a picture showing where you brazed in the return lines on the power steering tank?
Did you use a brass fitting?
Seems that a lot of us are doing the hydro boost upgrade, along with either a R & P, or steering box!
I like the idea of using the 13mm studs from an Astro Van H/B, and driving them in from underneath the pedal assembley, truly an evil job getting too that upper left nut, at times I thought I was going to loose mine!
My thanks to everyone who has written about this conversion,it sure has helped make things clear in my mind!
Somewhere, but just check Jim Shea's response to my earlier thread, he has photos and drawings of where to place it.
Not sure I agree with you about the 13mm bolts, why not just weld nuts on the inside of the pedal hanger bracket? Once it's back in, all you have to do is to insert the bolts from the engine side. And if you have to remove it for any reason, it's just so quick. Remove the clevis pin on the brake pedal, undo four bolts from the engine side, five minutes all up. Your call.
Regards from Down Under.
aussiejohn
Thread Starter
Race Director
Joined: Dec 2007
Posts: 14,345
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From: Hartselle AL
St. Jude Donor '09
BTAL,
I've just done this, but I've had to pull the Hydroboost out again. I stripped the thread on the HB low pressure return line fitting, and I'm having trouble finding the right fitting here in Melbourne. I know it's a 5/16" x 24 thread, but getting one with an AN -6 on the other end is the problem.
However, pulling the HB out is easy. When I'd pulled the old vacuum booster out, I went to the extra trouble of pulling out the pedal assembly. I then TIG welded captive nuts on the inside of the hanger bracket, 3/8" UNC. Then I just used 3/8" UNC bolts from the engine side of the firewall. Easy peasy. Makes it easy to remove the HB again if you need to, like I just did.
I also have the Borgeson box, but I removed the factory pump and took out the return line nipple. I brazed in a steel AN -6 male fitting in the stock location for the Borgeson return, then brazed in another male -6 AN for the HB return line. So all of my lines have AN fittings at each end. Cost a bit, but I'm not going to have to worry about it again.
I know you said you can't weld at home, but if you take the pedal hanger assembly to a local weldor, he will be able to do it for you.
Regards from Down Under.
aussiejohn
I've just done this, but I've had to pull the Hydroboost out again. I stripped the thread on the HB low pressure return line fitting, and I'm having trouble finding the right fitting here in Melbourne. I know it's a 5/16" x 24 thread, but getting one with an AN -6 on the other end is the problem.
However, pulling the HB out is easy. When I'd pulled the old vacuum booster out, I went to the extra trouble of pulling out the pedal assembly. I then TIG welded captive nuts on the inside of the hanger bracket, 3/8" UNC. Then I just used 3/8" UNC bolts from the engine side of the firewall. Easy peasy. Makes it easy to remove the HB again if you need to, like I just did.
I also have the Borgeson box, but I removed the factory pump and took out the return line nipple. I brazed in a steel AN -6 male fitting in the stock location for the Borgeson return, then brazed in another male -6 AN for the HB return line. So all of my lines have AN fittings at each end. Cost a bit, but I'm not going to have to worry about it again.
I know you said you can't weld at home, but if you take the pedal hanger assembly to a local weldor, he will be able to do it for you.
Regards from Down Under.
aussiejohn
Thanks for the reply. I see pulling the pedal assembly as just as big a job, especially if keeping the bulk of the dash and steering column installed. The goal is to keep the "dive under the dash" limited to connecting/disconnecting the brake pedal clevis pin. With the pull through serrated bolts, I hope to end up with the same result as you regarding mounting then, if ever needed, un-mounting the hydroboost.
Thread Starter
Race Director
Joined: Dec 2007
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From: Hartselle AL
St. Jude Donor '09
Instructor
Joined: May 2004
Posts: 185
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From: houston tx
how bout $10?
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Terrorizing Orange Cones
Joined: Oct 2007
Posts: 2,572
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From: Northern CO
For most of us, contorting one's body to reach the nuts securing the brake booster is a no-fun job.
Definitely, the way to go, especially with available serrated studs:
That lower stud spun on the serrations and I didn't feel like replacing it so spun a non-nylon locking nut on there. All's well and no more contortions next time I need to access.
Definitely, the way to go, especially with available serrated studs:
That lower stud spun on the serrations and I didn't feel like replacing it so spun a non-nylon locking nut on there. All's well and no more contortions next time I need to access.