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ramos291
09-15-2017, 03:54 PM
If you were to put on a salvaged car's brake booster what car would work on 61 thunderbird? I am using a 7" booster when I converted to disc front. That 7" booster is not doing the job. Thought would try a 9".

OX1
09-15-2017, 06:12 PM
I fit a 9" from a 79 f350, but it was a nightmare to fit. Search on my name for the thread and pics

stubbie
09-30-2017, 08:53 PM
I think you need at least an 8" booster for disk brakes. 7'' wouldn't have enough pressure. Maybe ring one of the brake company's to see if they can help like MBM brakes. Or look at 66 Tbird booster.

YellowRose
09-30-2017, 09:53 PM
I think you want to go with an 8" booster instead of a 9"... You might have difficulty shutting your hood with a 9" one. All of us who have done dual mc/power booster upgrades have used the 8" booster, as recommended by Dave ~ simplyconnected....

booalou
02-09-2018, 12:47 PM
Has anyone done the disc brake conversion using the stock mechanism with the 7 or 8" hotrod booster? If so did you cut the booster rod and add a heim bolt? How much did you cut off the bolt?

simplyconnected
02-09-2018, 02:22 PM
IMPORTANT: You need at least a DUAL DIAPHRAGM 8" booster for power disk brakes. Here is a picture and a link.

http://piratejack.net/universal-8-dual-diaphragm-booster/http://cdn6.bigcommerce.com/s-iykf1m/products/549/images/675/PB7537__31604.1446059524.190.285.jpg?c=2 (http://piratejack.net/universal-8-dual-diaphragm-booster/)

Notice, the 'step' on the RH side is for one of the diaphragms. A dual-diaphragm booster nearly doubles the boost of a single diaphragm booster.
Do not get a single & dual diaphragm booster confused. They are a lot different. This booster's major diameter (10") is the same as the OEM Squarebird boosters from 1960 but it delivers a whole lot more boost.

I'm using these in two heavy Fordoor cars and I love them both.

booalou, YES! If your Squarebird came with a booster under the hood you can cut the rivets off and mount this new booster to it. Many of our conversions used the existing firewall bracket.
All hardware from the OEM bracket to the pedal remains stock. - Dave

ramos291
07-09-2018, 07:06 AM
I am NOT having any good luck with this conversion. I'm afraid to drive my 61. Brakes seem more manual, not stopping well at all if I needed to panic stop. I'm not sure it's worth the switch. I may have to switch back to drum drum if I can't get it to work. After mounting booster to original bracket it's hit the shock tower brace. Still not locking brakes when using all my force on the peddle. Yes I've bleed the line and master more times then I can remember. Any one in Indiana with the fix here that can help me here?

ramos291
07-09-2018, 07:10 AM
Will this booster fit in the area without hitting shock tower brace?
IMPORTANT: You need at least a DUAL DIAPHRAGM 8" booster for power disk brakes. Here is a picture and a link.

http://piratejack.net/universal-8-dual-diaphragm-booster/http://cdn6.bigcommerce.com/s-iykf1m/products/549/images/675/PB7537__31604.1446059524.190.285.jpg?c=2 (http://piratejack.net/universal-8-dual-diaphragm-booster/)

Notice, the 'step' on the RH side is for one of the diaphragms. A dual-diaphragm booster nearly doubles the boost of a single diaphragm booster.
Do not get a single & dual diaphragm booster confused. They are a lot different. This booster's major diameter (10") is the same as the OEM Squarebird boosters from 1960 but it delivers a whole lot more boost.

I'm using these in two heavy Fordoor cars and I love them both.

booalou, YES! If your Squarebird came with a booster under the hood you can cut the rivets off and mount this new booster to it. Many of our conversions used the existing firewall bracket.
All hardware from the OEM bracket to the pedal remains stock. - Dave

DKheld
07-09-2018, 10:19 AM
I've had good luck using the original booster on my Squarebird.

https://storage03.dropshots.com/photos2/photos/260234/20051126/b_015151.jpg

It's been a little over 13 years since I converted mine. The pedal pressure is not as "light" as my 2012 truck but I don't have to have Schwarzenegger legs either. It feels basically the same as the old drum system but stops 100X better with the discs.

I'm sure I could get a "lighter" pedal using a dual action booster and it would surely be cheaper to rebuild or replace but it works great so I haven't fixed what isn't broke - :rolleyes: . On the plus side there was no mods needed to the pedal assembly or rod. Had to change to the booster face to a Lincoln to give the 2 bolt mount rather than the 4 bolt mount as original. (the Lincoln and Tbird booster were exactly the same except for the number of mounting bolts).

Can the OEM Tbird booster be used on the '61-'63? Just a thought. I bet it would fit without hitting - :D

Eric

YellowRose
07-09-2018, 11:20 AM
Some people have had to modify their shock tower brace to make this work.. Also, most of us use the 8" dual power booster and not the 9". In addition, you might want to use the Dual MC with the flat cover, not the Bubble cover, because that is what often can hit either the shock tower brace, or the inside of the hood when you close it.

simplyconnected
07-09-2018, 12:34 PM
If you were to put on a salvaged car's brake booster what car would work on 61 thunderbird? I am using a 7" booster when I converted to disc front. That 7" booster is not doing the job. Thought would try a 9".You leave a lot of important information out of your description of your system.

Thunderbirds came with disk brakes, starting in 1965. Is your booster a two-stage or single stage? In other words, was it designed for disk or drum brakes? Squarebirds use the two-stage booster because there is no more room to fit a booster diameter larger than 10". The OEM drum booster IS 10" but it is barely adequate for drum brakes. I've already gone over this.

What bore size is your M/C?
Did you use a combination proportioning valve?
What disk system did you buy?
Did you replace your brake lines and hoses?

Let's see pictures of your system. - Dave

ramos291
07-09-2018, 09:53 PM
What bore size is your M/C?
Did you use a combination proportioning valve?
What disk system did you buy?
Did you replace your brake lines and hoses?
The kit was from Auto city classic. MC is from 82 corvette. Yes I am using combo prop valve.
No I didn't replace brake lines but I did replace caliper hoses. What size brake lines should be used? My bird is a 61 tja t had power drum brakes original. The booster I'm trying to use is suppose to be an 8" single stage. Wish I could figure out how to share pictures. You leave a lot of important information out of your description of your system.

Thunderbirds came with disk brakes, starting in 1965. Is your booster a two-stage or single stage? In other words, was it designed for disk or drum brakes? Squarebirds use the two-stage booster because there is no more room to fit a booster diameter larger than 10". The OEM drum booster IS 10" but it is barely adequate for drum brakes. I've already gone over this.

What bore size is your M/C?
Did you use a combination proportioning valve?
What disk system did you buy?
Did you replace your brake lines and hoses?

Let's see pictures of your system. - Dave

YellowRose
07-09-2018, 11:03 PM
Randy, when you became a member on this Forum a good number of years ago, it was explained to you in the New Members Welcome Forum how to post pix on this Forum. To save you from having to find the post to you back then, here is the information that was posted to you that you need to know regarding how to post pix here.

As a Paid Member if you have anything you want to share with us you can post attachments directly on our server. To become one, have a PayPal account and click on the Donate to Site button at the top right of this Forum. To post attachments as an unpaid user you can create an account on one of the free picture hosting websites, upload your pictures of your Tbird there and post the link to them in Our Rides Forum. Or you can send them to me, Ray Clark ~ YellowRose, John Pizzi ~ jopizz, or Dave Dare, our webmaster ~ simplyconnected and we will post them for you. When you post pictures please set them for 800x600 size for better viewing on the Forum.

simplyconnected
07-10-2018, 07:48 AM
...The kit was from Auto city classic. MC is from 82 corvette. Yes I am using combo prop valve.
No I didn't replace brake lines but I did replace caliper hoses...Now we're getting somewhere. It's easy to understand why your performance is really poor.

The prop valve is good and so are your new hoses. What calipers are you using? Are they single or dual piston?

I live in the 'rust belt' so I will not trust 50 year-old steel brake lines. I've had too many spring a leak. The last OEM system leak happened in winter, 2 miles from home when I was sitting at the drive-thru window at a fast food place. My pedal slowly sunk to the carpet as I was waiting for my food in my Escort. And yes, it was rainy and cold. Called the flatbed.

Your M/C should have a one-inch bore. Not sure what size you have? Unbolt it and measure the bore. Many M/C's will allow you to do this without disconnecting hydraulic lines.

Brake lines are commonly 3/16". We use the same brake line for modern metric systems as well.

If a single stage 10" booster is barely adequate for drum brakes, a single stage 8" is miserably small for disk brakes. - Dave

ramos291
07-13-2018, 10:41 PM
thanks for your valid points.