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Discussion Starter #1
I'm doing an engine swap on a 66 Lemans for a guy. Out with 326 and powerglide in with 428 and built 2004r.
I fought to get it in and now that it is in, the giant power brake booster hits the valve cover.
I'll need to get a smaller diameter booster but figured before I just buy anything, I'd check here and get the right one.
Are all boosters created equal? Is a 7" dual any good? Or do I need to get something else?
Any and all suggestions will be appreciated.
Thanks
Danford1
 

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Sounds like you can put the correct 9" booster back in-place and get the clearance needed.
The factory booster (9") is readily avail; I just replaced the one in my '66.

As far as the reservoir if using a non-factory duel then there may still be clearance issues.
Some of the offerings are exceptionally wide, you might need to swap that as well with something closer to a '67 factory duel res.
 

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Discussion Starter #3
This is the booster that is in the car. It had clearance to the stock blue valve covers.
The other pic shows it hitting the new finned covers...
Can I just buy the booster and use the MC? If so, what part number do I order? I have O'Reilley, Napa, Advance and Autozone near me.

Danford1

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Obviously the finned valve cover is the problem.:frown3: I’ve seen this several times when non-stock valve covers are used, especially tall ones to clear the valve train. Various options:
1. Go back to the stock valve cover or get chromed stock style.
2. Trim down and blend the valve cover fins just enough to clear the booster then polish them up. I saw an article in Hemmings Muscle Car mag about a guy who did this in order to retain old 427 Ford valve covers on an engine swap. Even though this may provide clearance you still need enough room to get the cover off but your customer may not like this option. Can you even get the finned one off?
3. Change to booster to a smaller one. The parts stores you mention mostly carry stock size replacement boosters, each with their own part number, so you may have to special order or get one on line –getdiscbrakes.com-. Also, generally you will get the most power assist out of a larger diameter booster. Some smaller diameter boosters are "Dual Diaphragm" boosters. Because they have two diaphragms, a smaller diameter booster can provide as much power as a larger diameter single diaphragm booster, so it pays to do some research. The current MC should bolt right up and per your pics is not the clearance problem.
 

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Ah, the joys of aftermarket parts --- valve covers in your case. They very very frequently don't fit correctly.... :banghead: and wind up forcing you to spend hundreds of extra dollars on "everything else" just to make room for a $50 part.

You may get lucky, but more than likely "you're on your own" - which means you're going to have to figure out your own solution i.e. figuring out a booster that will both be compatible with your brake system and provide the clearance you need.

Or you could run different valve covers, or you could convert your brake system to a hydroboost setup, or move the engine over... :D (kidding)

Bear
 

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Discussion Starter #7 (Edited)
Obviously the finned valve cover is the problem.:frown3: I’ve seen this several times when non-stock valve covers are used, especially tall ones to clear the valve train. Various options:
1. Go back to the stock valve cover or get chromed stock style.
2. Trim down and blend the valve cover fins just enough to clear the booster then polish them up. I saw an article in Hemmings Muscle Car mag about a guy who did this in order to retain old 427 Ford valve covers on an engine swap. Even though this may provide clearance you still need enough room to get the cover off but your customer may not like this option. Can you even get the finned one off?
3. Change to booster to a smaller one. The parts stores you mention mostly carry stock size replacement boosters, each with their own part number, so you may have to special order or get one on line –getdiscbrakes.com-. Also, generally you will get the most power assist out of a larger diameter booster. Some smaller diameter boosters are "Dual Diaphragm" boosters. Because they have two diaphragms, a smaller diameter booster can provide as much power as a larger diameter single diaphragm booster, so it pays to do some research. The current MC should bolt right up and per your pics is not the clearance problem.

No the finned valve cover won't come off, it is pinned in there. I asked the guy he said he wants the valve covers to stay so I'll shop for a dual diaphragm booster.

Next problem :)

How the frick do you get the booster off? It has 4 studs through the firewall. I can see the 4 nuts but can only get a wrench on 2 of them. The bottom 2 look almost impossible with the engine in there. So then I thought I'd just take the booster off the bracket. Same thing. I can get the top 2 nuts off but not the bottom 2. How do you remove them? I've been working on cars for over 50 years... I've had hard to get at bolts but this is crazy. I can get a wrench on the bottom booster nuts but the wrench is trapped and can't be swung. I could see if I were to stand in the engine compartment with the engine out I would be able to reach them from underneath.

What is the secret?

Danford1
 

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Helped with a booster removal only once on a 65 and the bottom nuts are a pain to get off. There’s no secret, at least that I know of. It was trial and error with sockets, universal joints, extensions, and box end wrenches. We tried working from the top and bottom eventually mostly from the top. The wrench for the inside nut was lined up in the area of the voltage regulator and the wiper motor was removed to get at the outside nut. There was not a lot of room to swing the wrench. All I can suggest is try a bunch of different wrench combinations until one of them hopefully fits and allows for some movement. FYI, once the booster is loosened, the master can be removed and gently moved forward without disconnecting the brake lines as there is usually enough slack in the lines. Also, since the replacement booster is not “stock” I would verify that the current master will bolt on. If not, they usually give a good deal on booster/master combos.
 

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Discussion Starter #9
I looked at it again. Yes if I remove the wiper motor etc I'll have a smidge more room.
I thought a Maverick was bad. The bolts go from inside the car into the bracket. As bad as that was, this is much worse. At least you could get a socket and long extension in the Maverick.
I ordered a 8" dual diaphragm booster from Jegs. I hope I can get to the friggin bolts to get it in...

Danford1
 

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Discussion Starter #10
I tried again today and couldn't get at all the attachments. I pulled the engine and trans out and finally got all the nuts out. I'll be installing the new booster with the engine out for sure. This is ridiculous.
i wonder if whoever designed this ever tried to change one. I'm saying No, because if he did, he would change the design so it is possible to do...

Danford1
 

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That’s one way to solve the problem-sometimes you just have to bite the bullet. How these things are sometimes engineered is questionable. Changing the plugs on my 80 Cutlass and 93 Lumina was a nightmare.:cuss: While changing the booster is a pain, the service manual does not indicate the need to pull the engine. These cars are old and things like sagging frames and misalignment's can cause clearance problems. Non stock items can also have an effect. That brake setup looks aftermarket. GM started using dual masters in 1967 and on Delco/Moraine boosters the bracket was attached to the housing with a stamped stud/rivet, not bolted. But, someone was able to get the booster bolted in.:surprise: That said looks like you should be able to move forward smoothly. BTW, your pics linked to some other pics-what’s the story on that crankshaft?
 

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Discussion Starter #12
That’s one way to solve the problem-sometimes you just have to bite the bullet. How these things are sometimes engineered is questionable. Changing the plugs on my 80 Cutlass and 93 Lumina was a nightmare.:cuss: While changing the booster is a pain, the service manual does not indicate the need to pull the engine. These cars are old and things like sagging frames and misalignment's can cause clearance problems. Non stock items can also have an effect. That brake setup looks aftermarket. GM started using dual masters in 1967 and on Delco/Moraine boosters the bracket was attached to the housing with a stamped stud/rivet, not bolted. But, someone was able to get the booster bolted in.:surprise: That said looks like you should be able to move forward smoothly. BTW, your pics linked to some other pics-what’s the story on that crankshaft?
The crank is a Forged Eagle crank. From China .... It is for a Ford. It was in a Dart SHP block. That is an 8.2 deck small block Ford block. The physical size of a 302 but mine was bored and stroked to 376 cu in.
There HAD to be a flaw or defect in it as cranks don't break there like that. I was just cruising down the freeway at 2500 rpm when it broke. The engine had about 4000 miles on it.
I was on the Hot Rod Power Tour and of course it broke when I was over 1000 miles from home. I had to rent a U-Haul truck and a car hauler trailer and tow it home. No Fun !
I contacted Eagle but they said there isn't any warranty on race cranks, sorry...

Danford1
 

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Discussion Starter #13
Ok. Now I have another problem. I received the new booster today. It fits the car but not the MC. The old old had a long rod that pushed the MC. The new one is very short. I either have to send this back or get a MC that will work with it. AArrgg.

Danford1
 

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Sometimes on these custom boosters you have get the matching MC. Might be best to talk to a tech line rep directly to see what’s needed. And you thought this was going to be a simple swap. :banghead::banghead:
 

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Discussion Starter #15
I ended up buying another master cylinder that fit the booster. The booster and MC are installed now.
Now I can fight with the next obstacle, headers...

Danford1
 
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