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(Post Link) post #1 of 11 Old 13-09-16 Thread Starter
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Hi All

Can anyone recommend a Vacuum Accumulator for running aiding the brakes instead of using the plenum for vacuum .

or how much vacuum roughly would i need. as im thinking of keeping the hose connected to the plenum for the vacuum when throttle closed and on the same line and have a small air pump connected via pump input with 1 way valves where needed.

would this work ? it does in my head

Thanks

Last edited by mirlock; 13-09-16 at 18:44.
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Yes that does work and it is highly suggested in an after market turbo application as the standard one way valve could open under boost and kick back against the pedal, instead of assisting. The easiest is is to get a decent brake booster (check) valve (that operates on a turbo car) and a canister like a metal fuel filter as accumulator. Put it line with the current brake booster vacuum line.

http://www.ebay.co.uk/itm/Vacuum-Che...4AAOSwLs5XLbqA
http://www.ebay.co.uk/itm/GM-9015689...UAAOSwOVpXc~7R
http://www.ebay.co.uk/itm/VW-Beetle-...oAAOSwgApW~iIY

If you want to go completely off the manifold, most diesels and electric cars make use of a small vacuum pump, check valve and vacuum reservoir
http://www.ebay.co.uk/itm/VOLVO-C30-...0AAOSwGtRX1Vhh

EDIT: I am going to do it on my two boosted cars and on my high duration cam car.

I have had a situation coming off the throttle straight onto the brakes where there was very little vacuum assist (in my high duration cam car).

A mate of mine had his after market turbo car push back on his brake pedal on a track day

Last edited by Gertie; 16-09-16 at 12:10.
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(Post Link) post #3 of 11 Old 16-09-16 Thread Starter
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Quote:
Originally Posted by Gertie View Post
Yes that does work and it is highly suggested in a turbo application as the standard one way valve could open under boost and kick back against the pedal, instead of assisting. The easiest is is to get a decent brake booster (check) valve (that operates on a turbo car) and a canister like a metal fuel filter as accumulator. Put it line with the current brake booster vacuum line.

http://www.ebay.co.uk/itm/Vacuum-Che...4AAOSwLs5XLbqA
http://www.ebay.co.uk/itm/GM-9015689...UAAOSwOVpXc~7R
http://www.ebay.co.uk/itm/VW-Beetle-...oAAOSwgApW~iIY

If you want to go completely off the manifold, most diesels and electric cars make use or a small vacuum pump, check valve and vacuum reservoir
http://www.ebay.co.uk/itm/VOLVO-C30-...0AAOSwGtRX1Vhh
Thanks Gertie

As always to my aid and putting your time into helping , I must owe you a lot of beers now


Now i know what im going to order although i do already have the check valves that i ordered a while ago .

Nice 1 fella


Edit .. Oh dear nope its not good to have no brakes and push back must send you into a panic if trying to brake hard
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Quote:
Originally Posted by mirlock View Post
Edit .. Oh dear nope its not good to have no brakes and push back must send you into a panic if trying to brake hard
It really only happens if you go from full throttle to full brake in absolutely no time. If you give the throttle a small moment to close and create the vacuum, it generally is not a problem. For the little effort it is to install something like this, it is well worth the peace of mind
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(Post Link) post #5 of 11 Old 16-09-16 Thread Starter
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Originally Posted by Gertie View Post
For the little effort it is to install something like this, it is well worth the peace of mind

Agreed & i am ordering it the stuff now
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All bought Mr Gertie i think i got some good prices.

Im keeping the connection to the plenum with 2x 1 way valves 1 on plenum line and the other on pump (just a small pump to keep the tank topped up . im sure the pump should be good enough but if not i will get a more powerful one.

Tank = 6 inc post
Pump = 15 inc post
Valves = cant remember

Last edited by mirlock; 04-04-17 at 22:31.
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Those are good prices.

I'm getting trying to get my things together too...
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(Post Link) post #8 of 11 Old 21-09-16 Thread Starter
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Quote:
Originally Posted by Gertie View Post
Those are good prices.

I'm getting trying to get my things together too...
Ive had a thought Mr Gertie.

Do you think having the accumulator tank connecting to the plenum and instead of having a pump have a tube and valve connected to the inlet of the turbo which would create a vacuum as well would work ?
If it created enough vacuum you could bypass having a connection to plenum.
That way it cuts out the worry of electric pump failure & blow back

Last edited by mirlock; 04-04-17 at 22:31.
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That diagram only rely on on venturi effect of the high speed air passing by, the max vacuum you'll get is a very few millibar. You'll have to have a taper tube to create fair vacuum:
https://upload.wikimedia.org/wikiped..._venturi_1.JPG

The plenum is still your best source of vacuum - one is never on full throttle ALL the time (ok unless you are a biker going for it at Ilse of Man ) And that is the whole reason for the accumulator - to use those few moments of closed throttle to create DECENT vacuum in a short time that can be spent over a longer period. The vacuum pump + accumulator works the other way around.... One is not on the brakes ALL the time, so the pump trickles the air out the accumulator over a longer time that by the time you need the vacuum - there is sufficient vacuum.

You can use a combination of both too, but that is then just getting dual redundancy for a system that your gym fees can also pay for

Last edited by Gertie; 22-09-16 at 07:08.
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Your application is not a N/A tune with SOOOO much overlap, that there is no vacuum, ever. Your application is there are times of positive pressure to cater for.
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(Post Link) post #11 of 11 Old 22-09-16 Thread Starter
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ahh ok i shall carry on as i was . thank you again for your wise words
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