Brake boosters?

[TurboFource]

What is the story with brake boosters? I see people remove them and put in a different master cylinder. Were they needed on a car as light as an Europa?

[BDA]

Using a smaller M/C and booster delete is a common mod. The boosters do make a difference - otherwise, you wouldn't need to concern yourself with the smaller M/C, right?  Of course, the pedal travel will be a little bit longer with the smaller M/C.

I elected to use boosters on my car mostly because I liked the brakes when my car was new and stock and wasn't sure that I would like the longer pedal travel. I don't think I've ever heard a complaint about that from people who have gone that route. It certainly makes the plumbing a lot simpler and the whole thing less expensive. There's a lot to be said for the booster delete idea.

[jbcollier]

If you want to keep the boosters, make sure you buy new ones.  Rebuilt ones are fine for garage queens but a bit chancy for drivers.  Girling boosters are no longer available but Lockheed ones are.  Look a bit different but function essentially the same.

[Grumblebuns]

Anyone know the various failure modes for the Girling boosters?

Like BDA, I really liked and got use to working boosters on my TCS. Never really got use to the stock Girling M/C with EBC green pads on my S2. For the TCS, will be installing the Courier M/C until I can round up a pair of Lockheed boosters to an eventual return to boosted brakes.

Joji Tokumoto
Fallbrook, Ca 

[jbcollier]

Lockheed boosters are available at most British parts suppliers.  They even can supply them with a bracket that adapts them to the Girling mounting holes.

[Pfreen]

I installed a Duralast m51801 master cylinder with remote reservoirs.  It cost about $35 at Autozone.  If you have questions on how to do remote reservoirs, get back to me.  The remote reservoirs make access much simpler than the oem layout.

I removed the residual valves because the the reservoirs were above the calipers and rear cylinders.

Anyway, I have the lockheed boosters mounted in the front.  I just changed from Greenstuff pads to Mintex 1144.  I am very pleased, the problem is they squeal a bit.  The Greenstuff pads were very grabby with the boosters and I didn’t like them.

I posted some photos of the installation somewhere on this blog.  I could never find a Courier master cylinder but found this one.  It is .875” diameter.

I recently posted about front end lockup, but is is improving as the brakes, especially the rear shoes bed in.

[Certified Lotus]

I just deleted them and changed the master cylinder. No issue and you save weight taking everything out.

As I understand it, the only reason these were installed is due to government regulations that you have to have a brake fail indication that was pressure related and not fluid level indication. That the reason for all the extra plumbing, pressure switch and the boosters.

[TurboFource]

Certified,
I think I saw a Wilwood proportioning valve on you car? Was this part of deleting the boosters?

[TurboFource]

I just looked at a drawings of the brake lines with boosters on a Europa.
The craziest looking system I have seen

[jbcollier]

I run a single circuit system with no booster.  Works great and bleeding is a breeze.

[Certified Lotus]

Certified,
I think I saw a Wilwood proportioning valve on you car? Was this part of deleting the boosters?

I installed this for future change to rear disk brakes. The guy who was going to build these in Europe never did, so right now it’s just an in line valve wide open.

[BDA]

I just looked at a drawings of the brake lines with boosters on a Europa.
The craziest looking system I have seen

It would be a lot simpler if the front booster was in the front and rear booster was in the rear but because the vacuum source is in the rear, the boosters are in the rear (till I read Pfreen's post) so the front circuit goes back to the booster and then back to front. The rear circuit is much simpler. When the dual brake systems came, the PDWV and the extra booster made things a little more complicated still.

I'm happy with my boosters and if you use them too, you can mount them behind the rear wheels and you can use their original location for something else. I also like having two circuits rather than just one.

[Pfreen]

Actually, putting the vacuum boosters up front was not too difficult.  I ran a 3/8 ss tube from the engine to up front along the frame for the vacuum source.  The brake lines were there and only needed minor mods to make it work. 
I have also seen them mounted at 90 degrees in the original girling booster location. Literary madness’s car has the boosters in the rear behind the wheels.

I have never driven a Special without the boosters so I cannot comment on whether they are a good or bad thing.  I just know the braking right now is pretty darn good😊 and the pedal feel is excellent.

[BDA]

That's pretty cleaver, Pfreen!

[rjbaren]

I am doing a restoration of chassis 3525R a 73 Twin Cam Special.  I received the car as a basket case, it was disassembled 25 years ago.  The master was removed and it was stuck so I figured the boosters were not going to be any better. I have decided to remove the boosters.  Less complicated and less weight.  I replaced the master with a 3/4 inch Tilton universal.  I also bought a Jeg's proportioning valve but one of the members said it won't be necessary so I left the proportioning valve out.  I don't think I will have the car running again till next spring so in my case, the jury is out.