Show me your brake booster vacuum line setups

[jjvwg]

I am getting to the final steps of having my 2.7t motor ready to drop into my b6 swap and I have upgraded my intake to run the 034 85mm MAF housing and their silicon intake for the housing. Being that the intake doesn't have the bung where the stock vacuum line taps into I need to just run between the IM and the booster connection on the firewall and am wondering what parts/pieces/hose sizes/check valves people have run to accomplish this. I'm at work writing this so i don't have the measurements on hand but i believe the nipple on the IM is 21mm O.D. and the connection as the firewall is 14mm O.D. if i utilize the fitting that plugs into the rubber grommet. I also have a spare green check valve that I thought i might be able to use. Just wanted to see how some of you have set this up. pictures appreciated also. Thank you.

[Teck09]

The nipple that plugs to the firewall is a check valve in itself. I used that as well as the T fitting/check valve that split off to the stock accordian hose. I capped the second non checked outlet and will later use it for my boost reference line needed with a water/meth kit. I hope this is easily understandable. If not I can grab a quick picture to better show my setup.

[jjvwg]

yes, i understand what you're saying. I thought about that and its still an idea, just not sure how things will line up since im doing this on a b6 a4. I am also aware that there is a check valve on the on the firewall plug but i havent checked it yet to see if its still good and i thought about throwing another one in line for good measure. I feel like currently with the 1.8t i might have a leaky check valve on that booster line that is causing me to not get as good of vacuum assist as sometimes when in boost and then braking the brakes dont work as well as they normally do

[CJ_]

https://www.audizine.com/forum/showt...r-Hose-Removal

This is the thread I used back in the day. Theres a part number for a Porsche check valve that fits and pictures about halfway down. Its a pretty common check valve, I had a few laying around from just gathering spare parts. Cut off the connector for the IM, and attach a hose between the two.

[julex]

Brake booster is a very simple set up actually.

In its simplest form, there is a rather large line going from intake manifold into a check valve (air flow towards manifold) and then to brake booster. That's it.

More complicated set up is the one with jet suction pump which is a three port T looking piece. This should be connected behind the check valve I mentioned above on the booster side of hose, however I think that OEM check valve is actually before the Jet suction pump causing it to get pressurized all the time and eventually explore... One side has intake manifold line and the other a source of ambient air (accordion hose bung). The vacuum forces air flow from Accordion-->Intake Manifold when manifold is under vacuum in turn generating even lower vacuum on booster side port than manifold could normally generate with direct hookup, ventruli effect in its glory. The T connector has internal check valves as well.

[projectvoltron]

I am getting to the final steps of having my 2.7t motor ready to drop into my b6 swap and I have upgraded my intake to run the 034 85mm MAF housing and their silicon intake for the housing. Being that the intake doesn't have the bung where the stock vacuum line taps into I need to just run between the IM and the booster connection on the firewall and am wondering what parts/pieces/hose sizes/check valves people have run to accomplish this. I'm at work writing this so i don't have the measurements on hand but i believe the nipple on the IM is 21mm O.D. and the connection as the firewall is 14mm O.D. if i utilize the fitting that plugs into the rubber grommet. I also have a spare green check valve that I thought i might be able to use. Just wanted to see how some of you have set this up. pictures appreciated also. Thank you.

you can get a new brake booster check valve at any auto parts store. There are only a few bucks. I got one of those and put a hose clamp on that fat end that goes into the fire wall. Then just get a piece of fuel line or vacuum line and run it to the intake manifold. This worked for me on me b5 s4 and on my b6 a4 2.7t and haven't had a single problem.

We did the same thing on my brothers s4. Its cheaper easier and in my opinion cleaner

I don't have any pics on hand of what I did. But its pretty self explanatory.

Just get one of these valves at pretty much any auto parts store and 2 feet of line. I used the stock "quick clip" onto the intake manifold

brake booster check valve.jpg

[killerkali]

you can get a new brake booster check valve at any auto parts store. There are only a few bucks. I got one of those and put a hose clamp on that fat end that goes into the fire wall. Then just get a piece of fuel line or vacuum line and run it to the intake manifold. This worked for me on me b5 s4 and on my b6 a4 2.7t and haven't had a single problem.

We did the same thing on my brothers s4. Its cheaper easier and in my opinion cleaner

I don't have any pics on hand of what I did. But its pretty self explanatory.

Just get one of these valves at pretty much any auto parts store and 2 feet of line. I used the stock "quick clip" onto the intake manifold

brake booster check valve.jpg

I use that exact check valve in the same setup. Just an FYI for everyone to be careful, I had this one explode during a WOT 3rd gear pull and lost the power brakes. Had to literally stand on the pedal Lol. The back with the "+" is lightly glued or melted together.
Anyone know of a similar size check valve that is more heavy duty?

[projectvoltron]

I use that exact check valve in the same setup. Just an FYI for everyone to be careful, I had this one explode during a WOT 3rd gear pull and lost the power brakes. Had to literally stand on the pedal Lol. The back with the "+" is lightly glued or melted together.
Anyone know of a similar size check valve that is more heavy duty?

It depends on the autoparts store I guess. This isn't the exact on I use. Just a reference

That sounds sketchy as hell. Glad nothing bad came of it!

[jjvwg]

thanks again for all the help guys. i think my big issue was i was thinking of using the firewall fitting and not the manifold fitting so i was wondering where i would get a reducer of the right size for the hoses needed and trying to fit an extra check valve in. ill have to double check and make sure my check valve is good and by some hose.

has anyone tried to tee in the feed from the vacuum reservoir? I like how the b6 a4 setup has the vacuum reservoir tied into the booster circuit to help if coming straight off boost.

[julex]

thanks again for all the help guys. i think my big issue was i was thinking of using the firewall fitting and not the manifold fitting so i was wondering where i would get a reducer of the right size for the hoses needed and trying to fit an extra check valve in. ill have to double check and make sure my check valve is good and by some hose.

has anyone tried to tee in the feed from the vacuum reservoir? I like how the b6 a4 setup has the vacuum reservoir tied into the booster circuit to help if coming straight off boost.

"coming straight off boost" - you should have vacuum in your booster from last time you were in vacuum, it doesn't go away unless your check valve is bad ofc. This is unless you're doing a lot of brake boosting in which case amount of vacuum stored in factory systems will always be inadequate. If this is the case, what you should invest instead into is replicating tiptronic/RS4 vacuum sensor and pump system to have vacuum at all times.

[projectvoltron]

thanks again for all the help guys. i think my big issue was i was thinking of using the firewall fitting and not the manifold fitting so i was wondering where i would get a reducer of the right size for the hoses needed and trying to fit an extra check valve in. ill have to double check and make sure my check valve is good and by some hose.

has anyone tried to tee in the feed from the vacuum reservoir? I like how the b6 a4 setup has the vacuum reservoir tied into the booster circuit to help if coming straight off boost.

I have my vacuum reservoir deleted because I bypassed the n249 valve. I have not noticed any lag or any downsides as far as "lag" in the brake system. I have 18z calipers and They are very responsive even right after boost. Just make sure you have a good check valve and you should be golden.