Vacuum for a brake booster, manifold issue...

[RoverP6B]

I have a Rover V-8 and a decent downdraft 48IDF Weber setup to replace the twin SUs.... it has occurred to me that, as the Weber manifold is of the individual-runner type, its going to be difficult to tap vacuum off the new inlet manifold to power the brakes which is how its currently done

OK, the picture is for a Ford but you get the idea...

Any ideas for a solution ?  I am guessing I could make spacer plates under the carbs which tap intake pressure, and join these up somehow... but I am guessing there might be a more elegant solution...?

best

Graham Ware

[Moderator]

How would you feel about using an electric vacuum pump? (Example)

[roverman]

So many, much heavier cars were built, without power assisted brakes,(including disc in front). Is it that much effort ? Ever tried to stop a power assisted brake system, with a dead  engine ? Good Luck, roverman.

[DiDueColpi]

Hey Graham,
Your answer is in the ford picture.
The little polished pipe at the base of the #1 intake runner is likely a brake vacuum take off.
Each runner will have one that runs to the back of the manifold and joins up into a small plenum.
The plenum is then tapped for the booster or whatever vacuum driven device that you have.
This is also the way that you would supply a manifold pressure signal to a speed/density type fuel injection system.
Cheers
Fred

[RoverP6B]

Curtis: thanks that looks like just what I was looking for, much appreciated!

Art: I want to avoid re-engineering the P6B setup with a new non-boosted master cylinder if I can avoid it, its a 4 wheel disc brake setup and very good for its time... the electric motor making the suction looks like a simple solution

Fred: my manifold setup is literally individual runners and I dont want to start drilling/tapping that if I can avoid it. I appreciate that the Ford manifold pictured has this option, and apologies for the confusion, but my casting does not

Thanks to all who posted, very helpful!

Graham Ware

[tr8todd]

http://www.britishv8.org/Triumph/LorenzHassenstein-TR8.htm

Lorenze doesn't run a booster on this car and it stopped just fine last time I drove it.  FWIW, his car weighs over 3,000 pounds.