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How Well Will a 122s-1800s Dual Master Work Without a Brake Booster

vintagewrench

vintagewrench

Active member
Joined
May 9, 2016
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Paradise


The 1800s AC is not in the car right now (above) and I am restoring it. The original booster (identical to the 220 unit below) mounts on the inside of the black bracket in the center of the fender well.

Have owned and driven 122s and 1800s cars (15) for over 40-years and only the last two, a 1968 220 and a '67 1800s are equipped w/dual master cylinders with brake boosters.

Both cars have dealer-installed when new Frig-A-King AC units and with the compressor and hoses in place and the original Girling booster, access is mostly cutoff on the drivers side of the engine compartment below the AC unit and the booster (more so the 1800s).

All of the other earlier cars have had a single master cylinder and no booster so I know that the pedal has to be pushed harder to stop.

Anyone here that has had experience with the stock dual master and no booster?

 
Any plans to use a modern compressor in place of those huge, power sucking and vibration producing old piston compressors?
 
I had a stock dual mc, no booster, stock brakes. Stopped just fine for daily use, and some fade under heavy braking, but not noticeable if you are downshifting. Upgraded to a set of Wilwood rotors and calipers and the fade was unnoticeable, then upgraded the mc to match the calipers by the recommendation of the guys at Wilwood and now my fear is pulling my eyeballs out under heavy braking.
 
I know a lot of people ended up bypassing those boosters because they were fairly failure prone.
 
JohnMc said:
I know a lot of people ended up bypassing those boosters because they were fairly failure prone.
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Very. Mine had 3 different used boosters (one was ?rebuilt?) installed, all 3 ended up in the core heap. The only thing I?ve heard of that had been a reliable option was an mg remote booster. Saw one at ipd this year on a 122 and the owner was very pleased with the performance and it?s been going for a while.
 
JohnMc said:
Any plans to use a modern compressor in place of those huge, power sucking and vibration producing old piston compressors?
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Yes, I am about to order a new Sanden single-pulpy compressor to match the early-1970s Volvo AC pulley I am going to use.

cwdodson88 said:
I had a stock dual mc, no booster, stock brakes. Stopped just fine for daily use, and some fade under heavy braking, but not noticeable if you are downshifting. Upgraded to a set of Wilwood rotors and calipers and the fade was unnoticeable, then upgraded the mc to match the calipers by the recommendation of the guys at Wilwood and now my fear is pulling my eyeballs out under heavy braking.
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Thanks, this is good information. More Tomorrow
 
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My wife and I had a '66 1800S with un-boosted brakes, but had been upgraded to a dual circuit 68+ master cylinder. It was totally livable for me (6'0" / 200 lb) but required quite a bit of effort from the Mrs. who is about 3/4 my size. I mean it required more effort than my un-boosted '66 Beetle which still has 4-wheel drums, but it was not scary to drive or too fatiguing. It required a firm commitment, I'd say, but not a Herculean effort. So subjective...
 
Duder said:
My wife and I had a '66 1800S with un-boosted brakes, but had been upgraded to a dual circuit 68+ master cylinder. It was totally livable for me (6'0" / 200 lb) but required quite a bit of effort from the Mrs. who is about 3/4 my size. I mean it required more effort than my un-boosted '66 Beetle which still has 4-wheel drums, but it was not scary to drive or too fatiguing. It required a firm commitment, I'd say, but not a Herculean effort. So subjective...
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Thanks for your input, it is about how I remember the un-boosted single master 122s cars I had in the past.

cwdodson88 said:
The only thing I’ve heard of that had been a reliable option was an mg remote booster. Saw one at ipd this year on a 122 and the owner was very pleased with the performance and it’s been going for a while.
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The PO installed a remote booster from Sandex that is visible in the photo. Doesn't work all that well for me. No boost until pressing harder on the pedal and then it comes on all of a sudden with too much braking force.

Had any time to work on you 220?
 
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Been poking away at it to keep my mind right. Going through a rough patch in life so it’s been slow, and sometimes it’s hard to not start taking a baseball bat to it. My buddy just opened up a shop, and since the family time is no longer on the schedule, it should start getting some attention at a decent pace.
 
Skandix sells 2 versions of that booster. One of them is a cheap knockoff and the price reflects that. Maybe you've got a knockoff and that's why your booster is sticking

I prefer to have the original style boosters rebuilt since they fit in the original location and look better as well.
 
cwdodson88 said:
Been poking away at it to keep my mind right. Going through a rough patch in life so it’s been slow, and sometimes it’s hard to not start taking a baseball bat to it. My buddy just opened up a shop, and since the family time is no longer on the schedule, it should start getting some attention at a decent pace.
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Sorry to hear this, hope your friends shop works out for you.
 
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hiperfauto said:
Skandix sells 2 versions of that booster. One of them is a cheap knockoff and the price reflects that. Maybe you've got a knockoff and that's why your booster is sticking

I prefer to have the original style boosters rebuilt since they fit in the original location and look better as well.
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The PO that put the booster in was quite thrifty when it can to buying parts - this one must be the low-rent versions.

Ian, I agree with you about using an original, and one did come with the 1800S. The booster on the 220 was still working when it came off the road.

With an AC compressor, and a Girling booster in the standard place, it will be really hard to work on anything below them, let alone even keep the engine and that area clean, which is why I asked about braking w/out it.

Have also thought about putting a booster up front to the left of the radiator if necessary, but would prefer no booster at all (one more thing that might go wrong.)

Have not tried it yet, but if I disconnect and plug the vacuum line to the booster will the front brakes still work OK to experience how much pressure is required on the pedal?
 
Booster disconnected should be about the same feel as direct manual but may have more or less pedal travel, I would try it, with one hand on the handbrake and see what you think.
 
^ What he said. The pedal effort is about the same as with a single circuit system and no booster with the vacuum disconnected on a dual circuit system. You'll just have more pedal travel since the piston is still moving in the booster. If you want to de-clutter the engine compartment and are OK with the additional pedal effort, go ahead and remove the booster. Remember, it only works on the front brakes in a dual circuit system anyway.
 
The rain stopped and I removed the booster vacuum line today, plugged it, and took the car out for a 40 mile back road run to see how the brakes worked un-boosted; I was pleasanty surprised with the result.

The pedal pressure needed to stop w/out the booster in reality was only moderate and it was good to return to actual "pedal feel" and feed back that only a "old fashioned" un-boosted system provides.

The braking also feels like EBC claims of a 15% improvement in stopping with the green stuff pads is actually at work. The high pedal pressure normally needed to stop an 1800 or a 122S w/out a booster has not been needed w/these pads so far.
 
vintagewrench said:
The rain stopped and I removed the booster vacuum line today, plugged it, and took the car out for a 40 mile back road run to see how the brakes worked un-boosted; I was pleasanty surprised with the result.

The pedal pressure needed to stop w/out the booster in reality was only moderate and it was good to return to actual "pedal feel" and feed back that only a "old fashioned" un-boosted system provides.

The braking also feels like EBC claims of a 15% improvement in stopping with the green stuff pads is actually at work. The high pedal pressure normally needed to stop an 1800 or a 122S w/out a booster has not been needed w/these pads so far.
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That's great to hear. I'm putting my '68 220 back on the raod soon, I'll give them a go.:nod:
 
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