Brake Booster • The Dodge Challenger Message Board

by **MrMopar83** » 15 Jun 2001 4:27

I have a 71 Challenger and I just put a booster on it, but the booster does not line up with the original pedal. So I need to know what to do? A new pedal, is there an adapter. If so let me know how to get one. Thanks

by **dave-r** » 15 Jun 2001 8:29

There is a thing called a bell crank that fits between the two.

by **Matt P (Matt)** » 07 Jan 2003 3:35

I Know this is an old subject but i am planing on upgrading my manual drum brakes to power disk and you said that you need a bell crank to attach the booster to the pedal. Does anyone know where i can get/ find a bell crank? for a 1970 dodge challenger. Does any one sell this in a magazine?

by **Dave-R (Roppa440)** » 07 Jan 2003 12:58

This is the bit you need.

by **Matt P (Matt)** » 08 Jan 2003 3:23

Yeah, but where do u think i can find one of these to buy?

by **Dave-R (Roppa440)** » 08 Jan 2003 9:58

Either a junk yard or anyone building a race car. Drag racers always remove power everything.

I don't really want to sell mine though because i might want to restore my car back to original spec one day.

by **Dave-R (Roppa440)** » 08 Jan 2003 10:57

Here is a drawing of how it goes together.

oldpics/booster.jpg

by **Matt P (Matt)** » 09 Jan 2003 3:00

Thanks for the help! I am probably going to be needing one of these so if there is anyone out there is looking to sell there's i am interested!! Anyways thanks for the help and good luck with your cars!

by **Jay Gilmore (Mickey_mouse** » 15 Jan 2003 2:36

Try Duncan Watts Crewe Transmissions he often has these bits if you are in England

by **Christer** » 09 Nov 2003 21:36

One of the previous owners had modified the linkage between brake pedal and brake booster in an incorrect way. He had simply welded two rods togheter without any toughts of the need for the rods to rotate versus each other . (See pic). This modification caused one rubber sealing to crack inside the brake booster, and caused a whistleing sound inside the coupe when driving.

by **Christer** » 09 Nov 2003 21:44

How did I solve this problem? I bought a brake booster from one junkyard. It was said to be form a ´70 Chally. I think it is a correct booster because I have seen a pic of a Challenger with the same booster. It looks like this:

by **Christer** » 09 Nov 2003 21:50

The sad part with this junkyard booster is that there is a quite ugly home-made weld on the rod that goes through the firewall. (See pic)

by **Christer** » 09 Nov 2003 21:57

The question I ask myself is why on earth they have welded in this area. It seems very unlikely that the rod may have become cracked or rusty for instance. I think that they have welded in this area because they, for some unknown reason, wanted to shorten the rod. That is the best explanation I can come up with.

by **Christer** » 09 Nov 2003 22:01

I need some help from you message board readers: Do you think that my conclusions are correct or not. Can anyone measure in the same way as I have done in the two pic´s above?

by **Christer** » 09 Nov 2003 22:07

There is another thing that makes me believe in my "too-short-rod"-theory. The distance between the brake pedal and floor feels like it is a bit short (only 7cm between rear edge of pedal and floor)
(7cm is roughly a little less than 3 inch)

by **Christer** » 09 Nov 2003 22:15

....and there is a second thing that makes me believe in my "too-short-rod"-theory: Even if I adjust the brake pedal switch (see pic) as far out as possible, it won´t touch the brake pedal. Question: Does my brake pedal switch look correct?

by **Christer** » 09 Nov 2003 22:22

One last thing (I promise !!!!!!): The end of the booster-rod is too narrow to fit the lever arms of the bellcrank. Do I miss nay part or what? Any ideas or thoughts are much appreciated. Thanks //Christer

by **dave-r** » 09 Nov 2003 23:05

That booster of yours does not look quite right to me somehow.

The brake light switch looks how I remember mine but it has been a while since I saw it last!

The thickness of the eye on the rod on my booster is 15.2mm.

by **Christer** » 10 Nov 2003 10:58

Thanks for the quick reply.

The rod of the brake booster seems to be about 8 cm on both yours and mine booster. One difference is that you measure with the plate on and I don´t. The thickness of this plate is not more than about 1mm BUT a bigger difference is that bottom surface of your booster seems to be flat, and my booster is profile shaped (and I measure from the bottom of the shape!!) Conclusion: The "effective length" of your booster-rod is maybe 5-10 mm longer than mine. :idea:

Have I got it right?

by **Christer** » 10 Nov 2003 11:01

Wrong!!!! I realize now that I don´t know anything about your boosters shape/profile. All I saw on your pic´s was the steel plate! :oops:

by **dave-r** » 10 Nov 2003 11:37

Shall I take the plate off and take more pictures or measurements?

by **Christer** » 10 Nov 2003 12:02

It would be great if you could do the same measurement without the plate

(...and measure from the "low" part of the booster-surface)
Thanks in advance!

by **Christer** » 10 Nov 2003 15:30

On the other hand: I can measure the lenght with the plate on, so that you won´t have to do it.

by **dave-r** » 10 Nov 2003 16:58

OK.
You measure yours, I'll measure mine, and we will see who has the longer length? :oops:

by **Christer** » 10 Nov 2003 18:35

ha, ha, you won´t even come close....

by **insuranceguy** » 10 Nov 2003 20:41

Here is my non- technical cure! http://www.mpbrakes.com/CHRYSLERBOOSTERS.HTM

I just replaced the whole thing, makes life simple!

by **dave-r** » 10 Nov 2003 21:20

Well were is my 1969-70 booster with its back plate removed. Still looks nothing like yours mate. As for length (cough!) mine is 100mm from the back of the booster to the back edge of the rod (not the eye center). :roll:

by **Christer** » 11 Nov 2003 6:32

That is indeed a comfortable solution, Insuranceguy, but if you are running on a close budget.... :roll:

by **insuranceguy** » 11 Nov 2003 7:02

Now you know why I haven't painted the car yet! Too many gizmo's, not enough cash flow :roll:

by **Christer** » 16 Nov 2003 10:55

Do you know what? I have bolted everything back together and it seems to be working better than I had expected at first. I removed a gasket between the booster and the firewall to make the booster-rod a bit longer in an artificial way so to say. The brake pedal is now in a position where it can push-in the brake light switch. (I had made this gasket myself but I had not thought about these consequences. The gasket is only about one millimeter thick, but this millimeter probably makes the pedal height vary by 5 times that. Besides that, I still believe that the booster-rod is a bit shorter than it was from the factory. The difference in rod length is probably done by mistake, when they welded the rod).
My only concern is that the pedal height may still be a little low (too close to the floor). Anyway, I will start with this setup and see how it works with the engine on. Thanks for your help.