TC supercharger and brake servo.

[Ray White]

It has been brought to my attention that the TC which I am restoring has a potential problem. I have an Eaton M45 supercharger... but I have also fitted a brake servo (to help with a bad knee.)

The problem which has been pointed out to me is that the servo/booster is vacuum operated and the take off from the manifold will be of no use as the manifold is constantly under pressure from the supercharger. It would of course work with the original carburettors set up.

I wish I had thought this through before spending time and money on the servo. The Moss instructions show the booster take off from the manifold. I have been advised to fit a take off from the carb/supercharger mounting flange where apparently there will be sufficient vacuum for the servo ...but I am not sure....

[EdCallo]

This is a common issue with high output muscle cars, no vacuum for the brakes booster. Some use a vacuum reserve to save the vacuum from when they have it for when needed for the brakes. But that will not help you. Other solution is a vacuum pump. Places like Jegs and Summit sell them. Most of them are electric. Not sure a TC generator will have the extra power for the electric vacuum pump?

Ed

[Ray White]

I have removed the supercharger end plate, tapped a 1/8" BSP hole and attached an adapter.

Hopefully this will work O.K. (If not I have a 45 amp output Dynamator/alternator.)

[TC9800]

I also have an eaton 45 on my TC with a vacuum gauge. The engine will generate vacuum much of the time only producing positive manifold pressure on wider throttle openings. However the vacuum may not be sufficent for assisted brakes to be effective and a vacuum tank will not help in these circumstances. A vacuum tank cannot store any higher amount of vacuum than the engine generates, greatest on a trailing throttle. There will not be enough vacuum at idle which may be under 10". Your assisted brakes will require at least 15" of vacuum and an electric vacuum pump would solve your problem.

[Ray White]

I have taken the vacuum hose from the supercharger end plate. This apparently works but only time will tell

[rstarkweather]

Ray:

What exhaust manifold are you using? I also have an Eaton 45 on my car and am thinking about switching from the current "outside the frame" manifold to one that tucks inside like yours.

Rick

[Ray White]

Ray:

What exhaust manifold are you using? I also have an Eaton 45 on my car and am thinking about switching from the current "outside the frame" manifold to one that tucks inside like yours.

Rick

HI Rick. I have a stainless steel exhaust system with an extractor manifold. Be careful though because I had no end of trouble with mine. It meant fitting a smaller starter motor (I opted for a high torque one) and it also fouled the clutch operating lever and the steering drop arm. I had to get the manifold - which was very expensive to start with - re shaped by a specialist.

I wish If I had gone to them in the first place.

I understand you can get extra HP but there is also extra heat and noise to consider. As we know, sound deadening costs money and adds weight.!