i have a problem....
my car doesnt make enough vacuum to fill the booster for the brakes. it makes about 10psi of vacuum at most after the turbo conversion.

Ive connected the booster hose to the plenum, is there somewhere else that is better suited??

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Driving takes three abilities: Accelerating, braking, and turning.
More power only helps acceleration.
Lower weight helps all three.

If there isn't a one way valve in the booster hose I would suggest fitting one.
This will prevent the vacuum tank of the booster from losing vacuum during driving and allow it to retain the maximum level of vacuum for the next application of the brakes.
Every time you back off the throttle the throttle valve will close and the engine will develop high vacuum to replenish the tank.

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Regards, Graeme
Just trying to help...
http://nissanman.shutterfly.com/
graemes@internode.on.net

psi is pressure per square inch so you cant make 10 psi of vacum

is it producing 10 pound of boost pressure or -10 vacum

is the booster in good cond ,no holes in diaphram?
some volvo's have a little vacum resivoir under the dash for this problem.,ive got a couple for big cam motors that produce little vacum

I will be putting my L20b turbo into my car soon,so i might run into the same prob
had it in another 1600 but we didnt run a brake booster

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68 510 - soon to be restored into a replica 68sss
69 510 - current build - L20b turbo
91 GT turbo legacy
GET THAT DATSUN DIFFERENCE!

booster is new with no faults, it does hold vacuum... the problem is my motor doesnt make enough vacuum (-10 vac thanks driftdat) the size of the cam is the issue
this only gives me enough for 3/4 solid push on the brakes after that its how hard my foot can push..

i was even thinking of using a deisel alternator!?! would this work??

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Driving takes three abilities: Accelerating, braking, and turning.
More power only helps acceleration.
Lower weight helps all three.

If the cam prevents the engine from generating sufficient vacuum, you really need an independent vacuum pump.
These are electrically driven.
A lot of Cruise Control modules have their own vacuum pump supply.

http://store.summitracing.com/partdetai ... toview=sku

_________________
Regards, Graeme
Just trying to help...
http://nissanman.shutterfly.com/
graemes@internode.on.net

Diesel enginess dont make vacuum, therefor they usually have an alternator equipped with a vacuum pump.

does anyone know if i could fit a diesel alternator of a 720d onto my L20 without any major hassles

_________________
Driving takes three abilities: Accelerating, braking, and turning.
More power only helps acceleration.
Lower weight helps all three.

not to sure but sounds like a good idea ,cant really see why it wouldnt work

_________________
68 510 - soon to be restored into a replica 68sss
69 510 - current build - L20b turbo
91 GT turbo legacy
GET THAT DATSUN DIFFERENCE!

you still should have some vacume on overrun with the throttle body closed

at idle in the driveway there would be bugger all vac with a big cam
this happens to my motor albeit n/a, a few blips of the throttle should get the booster working again although times of sufficient vac will be periodic in your motor if dirt racing.

maybe consider a vac reservoir to store additional vacume as you are getting some...

oh vac is measured in inches of mercury (in/hg) for all those playing at home

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"the 910 is the poor man's 510"

or here in Australia, mm Hg