Is anyone running a 360 in an early A with the 8" power brake booster? If so, can you post a picture of it an the clearance between the booster and the valve cover? I was mocking might up recently and it looks like I need to modify the bracket to move it up 2" to clear the valve cover. Even then, getting the valve cover off will suck. Also considering going to hydro boost to get some service clearance. Let me know what you have/think.
Early A with 360/power brakes
- Thread starter jw133489
- Start date
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396 Signet
Well-Known Member
Power brakes are not needed if you size the master cyl properly. The factory PB setup used a special bracket/ linkage which raised the booster to clear the valve cover.
Port brakes is something I decided I want on my car. I have driven one with manual brakes for a number of years and now prefer power brakes.
I also have the bracket and linkages. They just are not positioning the booster high enough to clear the valve covers. I am assuming it is due to the higher deck height of the 360 vs. the original 273 coupled with the MP aluminum magnum valve covers but would like to see what others have done.
This,
Jesse
I also have the bracket and linkages. They just are not positioning the booster high enough to clear the valve covers. I am assuming it is due to the higher deck height of the 360 vs. the original 273 coupled with the MP aluminum magnum valve covers but would like to see what others have done.
This,
Jesse
Bueller?
grumpuscreature
Resident Curmudgeon
First off, there is zero difference in deck height between a 360 and a 273 and the valve covers are maybe 1/4" taller at most. What year brackets and linkage did you use? If they are not '66 or older they will not fit properly. The problem is that early A's were designed to accept a slant six, period. A V8 is a shoehorn job and there just isn't room in the engine bay for a lot of useless frippery. As mentioned before power brakes are not needed if the master cylinder is sized properly, especially in a 2700 pound car. Before you go to the expense and hassle of trying hydroboost or a smaller vacuum booster, try a master cylinder from a '74 Charger with manual disc brakes. It has a 7/8" bore and if you never saw it on the firewall you would swear the car had power brakes. It's the only one I use for my cars and is available at any parts store for around 30 bucks. I don't like the stock "standing on a rock" manual masters either. That's why I bolt up the Charger cylinder every chance I get. Good luck.
I use this in my 62 Valiant with 273 cui.
http://www.ebay.com/itm/Mopar-7-pow...pt=Motors_Car_Truck_Parts_Accessories&vxp=mtr
http://www.ebay.com/itm/Mopar-7-pow...pt=Motors_Car_Truck_Parts_Accessories&vxp=mtr
BillGrissom
Well-Known Member
I have power brakes in my 65 Dart. I used brackets from a 74 Dart and booster/MC from a ~98 Breeze. The booster clears my Wiend valve cover with ~1/4" to spare. That is with new original (thick) motor mounts. I expect to get a little more clearance as the mounts age. I will have to unbolt the booster to remove the valve cover, but that might be true even with a factory early-A setup (anybody?). I used flexible brake lines from an Intrepid, so won't have to disconnect the plumbing.
Looks like you could just add a few washers to the bottom bracket - firewall mount to tilt it up a bit. If that scares you, GM's A-bodies tilt way up for power brakes. If you really tilt it, install an MC from an Intrepid which has a tilted reservoir.
Looks like you could just add a few washers to the bottom bracket - firewall mount to tilt it up a bit. If that scares you, GM's A-bodies tilt way up for power brakes. If you really tilt it, install an MC from an Intrepid which has a tilted reservoir.
I have a '65 Barracuda with a 360 and I once used your exact setup. I found that the booster fit well enough without touching the valve covers. Eventually I removed that vacuum booster setup in favor of a Hydroboost setup. That 8" vacuum system has a threaded, adjustable piston that slides suggestively into the master cylinder. It took me a great deal of trial-and-error to get that distance exactly correct. If it is too long, as it was in my case, the pressure put into the master cylinder disallows brake fluid to return. If that happens, you get a firm pedal but no brakes.
Here's a pic of my current Hydroboost setup. You can see that there's only a half inch of space from the flange where the booster bolts to the master cylinder. I rarely if ever pull my valve covers, so it's not an issue for me.
If you go with Hydroboost, be absolutely sure to make the modification to the small, removable valve body from your pump to reduce the pressure. I found that having the stock high pressure (I think something like 1350psi) valve setting, I could screech the car to a stop regardless of speed with just a smidge too much foot pressure. After the modification, it feels perfect. It drops the pressure down to something like 850psi. It really makes all the difference and now the brakes feel absolutely perfect. Very powerful and predictable. Here's the article:
[ame="http://www.moparaction.com/tech/beep/PUMP_IT_DOWN-re-v1.4.pdf"]www.moparaction.com/tech/beep/PUMP_IT_DOWN-re-v1.4.pdf[/ame]
Please ignore the inevitable comments of "you don't need power brakes" that always show up in power brake discussions. That's unhelpful, non-technical drivel.
Here's a question: what kind of brakes do you have? Disc? Drum? Size?
-marcus
Here's a pic of my current Hydroboost setup. You can see that there's only a half inch of space from the flange where the booster bolts to the master cylinder. I rarely if ever pull my valve covers, so it's not an issue for me.
If you go with Hydroboost, be absolutely sure to make the modification to the small, removable valve body from your pump to reduce the pressure. I found that having the stock high pressure (I think something like 1350psi) valve setting, I could screech the car to a stop regardless of speed with just a smidge too much foot pressure. After the modification, it feels perfect. It drops the pressure down to something like 850psi. It really makes all the difference and now the brakes feel absolutely perfect. Very powerful and predictable. Here's the article:
[ame="http://www.moparaction.com/tech/beep/PUMP_IT_DOWN-re-v1.4.pdf"]www.moparaction.com/tech/beep/PUMP_IT_DOWN-re-v1.4.pdf[/ame]
Please ignore the inevitable comments of "you don't need power brakes" that always show up in power brake discussions. That's unhelpful, non-technical drivel.
Here's a question: what kind of brakes do you have? Disc? Drum? Size?
-marcus
in the front I have disc-brake from a Dart -71, in the rear I have build my own disc-brake with disc from Toyota and calipers from Peugot.
moparlee
64 Valiant
Bake in the 90's when I snagged all the upper control arms and spindles off a 74 model A-body had also grabbed the brake booster parts. I had also put an 8 1/4 rear with the 10x 2.5 brakes. It worked great.
I've since went manual with four wheel disk brake set up. The same 74 model stuff in front with Grand Cherokee rear disk set. It works amazing too.
Later I used the same special bracket for the booster for my 86 Dodge Ramcharger to be able to clear the valve cover easier. I've since put the four bolt to two bolt adapter on the booster to run the aluminum master.....just because that brand new master was wet/leaking all the time.
I've since went manual with four wheel disk brake set up. The same 74 model stuff in front with Grand Cherokee rear disk set. It works amazing too.
Later I used the same special bracket for the booster for my 86 Dodge Ramcharger to be able to clear the valve cover easier. I've since put the four bolt to two bolt adapter on the booster to run the aluminum master.....just because that brand new master was wet/leaking all the time.
So the difference I am seeing in my setup versus the ones that are being posted is the MP magnum valve covers are wider (and possibly taller?) than the LA valve covers.
The brake booster setup I have is like the one that Moparlee posted. I am thinking my options are to either scrap the power brakes idea (not my favorite), modify the mounting brackets for the booster to sit 2 inches higher (will still clear hood but with change the angle of the rod to the pedal), go hydraulic, or try different valve covers(using Indy magnum X heads), comments on the various options?
What about a hemi offset booster bracket?
The brake booster setup I have is like the one that Moparlee posted. I am thinking my options are to either scrap the power brakes idea (not my favorite), modify the mounting brackets for the booster to sit 2 inches higher (will still clear hood but with change the angle of the rod to the pedal), go hydraulic, or try different valve covers(using Indy magnum X heads), comments on the various options?
What about a hemi offset booster bracket?
moparlee
64 Valiant
Are you using stock valve covers and motor mounts? I don't remember having issues with the valve cover.....but I had stock valve covers on a 360 heads on a 318 back in those days.
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