Some engines don't produce enough vacuum to operate servo assisted brakes and other vacuum dependent system to their optimum. This is particularly true of engines that have high lift, long duration camshafts.

The eVac system generates vacuum independently
from the engine. This means that the vacuum supply
is kept constant regardless of engine RPM and load.
This constant depression results in a consistent weighting to the brake pedal in all conditions. The increased vacuum levels that can be achieved with this system
can allow less pedal force to be exerted by the driver to achieve the same or more retardation on the brakes.

The eVac system utilises the largest Hella vacuum
pump available to achieve maximum vacuum quickly
and efficiently. The pump is of a vane type construction and is therefore much quieter in operation than an equivalent sized piston pump.

The Anodised aluminium  valve block houses a high
flow one way valve and adjustable pressure switch.
Two 3/8" (10mm) hose tails are provided for vacuum take off. Other ancillary vacuum operated devices can
be connected using the 2 addition ports located on
each end of the distribution block.


Taylor Automotive Engineering

Unit 3 Willow Farm

Scrapers Hill


East Sussex


Telephone: 01825 873578

Email: geoff@taylor-automotive.co.uk

Technical Data


Operating temperature range – 40 °C to 120 °C

Voltage range 10 V … 16 V

Maximum vacuum level ≥ 86%
(below ambient pressure level)

Pressure build-up time at 100 hPa
pabs = 500 mbar in t ≤ 3.4 sec
pabs = 300 mbar in t ≤ 6.6 sec

Ambient pressure 12 V Test volume 5L

Pump operating time ≥ 1200 hours

Servo connection

2 push on hose tails for 3/8" I.D. servo pipe

1/4 BSPT threads

Spanner size 15mm

• 2 additional connections 1/8 BSPT thread

• Allan key size


20 Amp circuit breaker

25 Amp micro relay with EMF diode

Main battery connection wires - 2mm² (red/black)

Ignition sense wire 0.5mm² (purple)

Adjustable vacuum switch

Normally Closed

Adjustable between -200 to -900 mbar

Max switched voltage 48V

Max switched current 0.5A

1/4 BSPT thread

15/16 Spanner size


304 stainless steel 1.5mm thick

• 3 X 8mm mounting holes

Complete system weight = 2.32Kg

Made in England

The pump is controlled by the adjustable pressure switch and a micro relay.
The pump system is protected by a 20 Amp circuit breaker.

The system is all contained and mounted on a stainless steel bracket with
3X8mm diameter mounting holes.

The eVac system has been designed to be universal and can provide enough vacuum for up to two servos. It can be used on any vehicle that utilises a pneumatic servo to assist braking including hybrid and fully electric vehicles. It is capable of replacing the original vacuum system on a vehicle or can be used to supplement the original system.