Brake booster and ITB's on 16v

[harkes]

Hi

How do you guys get a good vacuum for your brake booster? Compared to a blacktop the vacuum is ok but the amount of air being sucked by the itb's is much lower, hence the brake pedal sinks much slower turning on the engine. Is the best sollution to mount fittings (green) and use a plenum? At present I am only using the two standard ones (circled red).

What have you guys done?

- Niels

[apardal]

I have four fittings with the T3 adapter plugged to vacuum tank that is connected to the brake booster.

Works fine!

[fax0815]

I´d also suggest a vaccum tank, it will also give you a more stable MAP signal.

[harkes]

apardal:

Whats the inside diameter of the nipple fitting on the adapter?

[apardal]

harkes Wrote:apardal:

Whats the inside diameter of the nipple fitting on the adapter?

WOW. Tough to tell. Gotta disassemble and measure. I would say 2/3 mm.

[assassin10000]

Tap the bottom of your adapter plate in all 4 runners and route to a vacuum manifold for your MAP & FPR vacuum source.

The booster you can run off a SINGLE runner. A 1/8" NPT or BSP fitting with 3/8" hose barb in the side of the #4 runner works.

Andrew

[harkes]

Hi guys

I am reopening this thread as my new engine is now finished and running but I have still got problems with vacuum for the brake booster.

I am using silvertop ITB's sourcing the vacuum from these 4 barbs on my adapter (see pictures) - connected to a plenum and then to the booster...

Why does this not work???

- Niels

[Uzelac]

I suppose i will have same problem with my Hayabusa ITB's.

They have 8 barbs, two for each TB.

Can i use one of each for MAP and the other one for brake booster ?



Or i must take vacium for brakes on some other place.

Regards

[jondee86]

Quote:1. Brake vacuum from side of throttle 1 behind butterfly (big hole)

2. Fuel return to tank (entry) [from regulator]

3. Fuel return to tank (exit) [to fuel tank]

4. Brake vacuum from side of throttle 4 behind butterfly (big hole)

5. Idle Speed Control Valve (ISCV entry)

The brake vacuum is taken from throttle 1 & 4 via a side port. They are
summed by a T-joint before connected to the brake servo. Since throttle
4 is far from brake servo hence it is connected to another pipe then to
the T-joint (not shown).

As can be seen, the factory thought that pulling vacuum from throttles
one and four was a good solution. Obviously, pulling vacuum from all four
throttles would be better. Likewise, keeping the brake vacuum separate
from the FPR and MAP signal vacuum is also a good idea

Picture and text courtesy of my-acoustic.com

http://www.my-acoustic.com/Car/car_section.htm

Cheers... jondee96

[4000GT]

Or just dont run a booster?