Power brakes??

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cuda620

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I have a 76 duster thats a smallblock now. I'm planning a Schumaker kit. I have a complete 440,but also have a 400 I could do a 451 stroker with. I'm planning to keep my power steering,power brakes,and AC. Smaller Sanden type compressor. I'm gonna daily drive this thing 6-8 months a year to enjoy it. Last A body 440 I did was a 68 cuda 30 years ago,All manual hotrod and simple. used a D.C.K-member. Times have changed. I'm gonna overdrive it,103 bars, front and maybe rear sway bars. QUESTION: Will my power brake booster clear the 440 or will I need to use the B engine?
it appears that my brake booster is up higher on the firewall with the mounting bracket it has. Appears to be a cantilever pushrod design. Rod from brake pedal comes in low,connects to lever,then a pivot on lever goes to a rod thats higher up and goes into the booster. Kind long post,but seeking as much info as possible before I do this. I'm hoping Mcleod comes out with their 5 speed for mopars so I won't have to cut the floor. Anyone help on the brake thing? Thanks.
 
So I've seen 440 darts with PB. With that said head will have to be something short, not the new TrickFlows which are taller (found that out the hard way). Its up to you but if you're looking for just ease of install the 400 would be easier from an interference prospective.
 
Agreed,the B would be much easier cept for the cost of building it. The 440's low miles and needs little cept aluminum parts. I may have to just stroke the 400 using a 440 crank and rods. Saves me some money over the chinese stuff. Just lookin for anyone who did it with the 440 and PB. Thanks.
 
I've got a small diameter booster and master cylinder here that was purchased for a BB in a-body build ( I don't recall year model A ). The original owner used a torch to blow out the mounting holes in the bracket so he could shift the booster left another 1/2 inch. After he's all done he found he didn't have enough vacuum to operate the brake booster.
Lesson learned... if you plan to cam it up, manual brakes will stop it.
 
Lotsa guys say our As stop just fine without the booster. Some even say better.
I say; I love my booster. A well engineered brake system, With a booster,IMO, is hard to beat. The trick is to not over-boost it. Having driven many, and mostly, A-body Mopes since 1969, I have had the opportunity to drive every combo they had, and my opinion will not change when it comes to brakes. Unfortunately, my opinion also concludes that most of the factory stuff was not engineered for us,today; so you have to re-engineer it. For you personally, your tires, your driving style, and your expectations/preferences.
As for me, the booster stays on, and not cuz my old leg is feeble either.

FWIW; I have been pleasantly surprised to learn that most of our boosters will work with low manifold vacuum, most of the time. Mine has worked down to 8 inches. If the car has been sitting long enough that the booster has lost it's vacuum, it's just a matter of momentarily bringing up the rpm to recharge it.The checkvalve will do the rest. This usually happens all by itself during the warm-up period,cuz if it's not on the fast-idle cam, you are blipping the throttle to keep it running.
Mine is good for at least one long application, even with the engine shut off at 65mph.
 
Just clarity's if the booster would clear. Wanted to see if anyone knew instead of finding out the hard way. manual master cylinder is mounted lower in line with the brake rod from the pedal. My power unit is raised up. Figured someone had dealt with that. Thanks anyway.
 
For a while, I had that small, dual diaphragm, offset-raised booster on my car. With a small block in there, there was a lot of room under it. a lot. I wasn't real happy with that booster, even tho there was nothing wrong with it, so eventually I swapped it out.
But sorry, no BB here.
 
Thanks for the info. I've had some smallblocks and poly mopars with power brakes,and yes,alot of room. I got time so I'll keep researching. I'm sure someone else has dealt wiyj yjis. I guess the bracket and raised power booster was common in many A bpdies from early 73 and up. More so when they went to the spool type engine mounts. I just want to buil it once.
 
Put a good 1" Wilwood manual master cylinder on it. The pedal will be way more consistent and it saves a ton of room. Also don't have to worry about what cam to run to have vacuum.
 
If you ever get up north you can stop by and look at my low deck with power steering and booster - Syracuse Indiana
 
I saw a 73 Valiant with a 400/B that had both So I figured I could run that. I'd have to build something,,, 451. But I also have a 440 with low mles and was curious about it clearing my setup. Dartsport, How much of the torsion bar crossmember did you cut out for the TH400?
 
cuda620 said:
I saw a 73 Valiant with a 400/B that had both So I figured I could run that. I'd have to build something,,, 451. But I also have a 440 with low mles and was curious about it clearing my setup. Dartsport, How much of the torsion bar crossmember did you cut out for the TH400?
Click to expand...

I will find out soon. I will be putting the trans in the car with in the next couple days. I'm waiting for the trans to finish getting built.
 
The car is long gone, but I had a 70 Dart that had the small Kelsey Hayes power brake booster in it. Someone before I got it installed a 69 440 in it and left the booster in place. There was some clearance with the valve cover but it was tight. The biggest issue I had was the booster was bad; I ended up pulling master cylinder and booster and going with a disc brake master cylinder and swapping the 10 inch drums with 73-76 discs - stopped MUCH better!
 
I have a 68 GTS with a 440. I tried to get a booster to fit, would not. I am using shumacher mounts and I think they sit the engine a little higher then stock. That MIGHT make the difference.
 
Tim
You say a booster. A single diaphragm non-offset, regular sized one(Ima guessing 10 or 11 incher?
Or the dual-diaphragm,offset,mini booster?Which is at least 2 or 3 inches smaller and offset-raised in the neighborhood of 2.5 inches?
If I had to guess, I'd say the mini is about 3 plus inches higher.
 
I had the original booster from the 68 when the 340 was in it. A raised, 10.5 inch I think. Original style mounting.
And for info, the engine hits the blower motor on the right side, so I was thinking the mounts were making the engine higher, that would give me less clearance on the driver side as well.
 
I'm not a fan of power brakes in an A-body so I've never tried to fit the booster with a B or RB, BUT I have run the AC system and power steering in my old '67 Barracuda fastback with the transplanted 383.
 

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Mopar Tim said:
I had the original booster from the 68 when the 340 was in it. A raised, 10.5 inch I think. Original style mounting.
And for info, the engine hits the blower motor on the right side, so I was thinking the mounts were making the engine higher, that would give me less clearance on the driver side as well.
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Yeah that's the one, the 340 one with the bellcrank linkage!That's the smallest, most offset, OEM booster arrangement, I have seen.It's not real happy with low vacuum engines.
 
AJ/FormS said:
Yeah that's the one, the 340 one with the bellcrank linkage!That's the smallest, most offset, OEM booster arrangement, I have seen.It's not real happy with low vacuum engines.
Click to expand...
No it is not. I was going to fab something up to get the needed clearance, might be part of my 68 Dart refresh in the works. Was looking at the Van setup how it puts the MC sideways. Was not going to use as is but I think I might be able to get an inch more clearance by moving to the left some.
 
Mopar Tim said:
No it is not. I was going to fab something up to get the needed clearance, might be part of my 68 Dart refresh in the works. Was looking at the Van setup how it puts the MC sideways. Was not going to use as is but I think I might be able to get an inch more clearance by moving to the left some.
Click to expand...

Gotcha!
I checked my FSM; In 1969, the bellcrank could be had on three different units;
The one I'm thinking of is called a Midland-Ross Tandem Diaphragm.No other info in the brake section.
 
My 75 dart with a 440 and schumacher kit clears the booster. Pcv valve is pretty close though. That's with stock valve covers.
 
May I see a picture of your brake booster setup? Is it a small diameter or the standard 12"?
 
I will try to post a pic. It's the original booster to the car. Sorry about the upside down pic! Haven't got that figured out yet!
 

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