nu2teg

Like the title states, I'm trying to figure out which would be the better setup for vacuum to run all the components on my turbo build. Ie; wastegate, bov, boost gauge, boost solenoid, brake booster, etc.
manifold currently has no vacuum sources at the moment, alum manifold, previous holes in manifold, threads were all stripped, welded them up. Now trying to decide whether to drill and retap for new connections or just put one going to a vacuum block.

TheShodan

iTrader: (14)

Vacuum blocks are best. Especially coming from the brake booster as the main source. wastegate vacuum source from the intake manifold itself or a "T" from the vacuum block to the Intake manifold.

motoxxxman

what ^he^ said.
If you T into the brake booster hose, just make sure it's before the check valve lol, as visible in his picture.
Also, the key to using a vacuum block is to make sure the hose for the vacuum source is large enough, 1/4" should do the trick. reason being that a lot of air needs to flow in and out of the block at all times, and you want it to be capable of flowing enough to not cause a delay in pressure equalization, otherwise you can get incorrect readings for sensors, and improper operation of certain parts, and boost level issues of compressor surge.

nu2teg

Thanks guys.
How about a particular place in the manifold to place the new port for the most vacuum? Top, bottom, middle, end of the manifold?

TheShodan

iTrader: (14)

Anywhere in the plenum is fine.

90HFCrX

Question I see that's the vibrant vacuum block the hose the connects from the vacuum block to the t fitting. What size fitting is that on the vacuum block? I see the vibrant vacuum block comes with 1 3/8npt port. And 6 1/8npt ports from what I've searched. Also what size is that T fitting? 3/8? I would like to run this exact setup on my eg hatch soon to be boosted. Thank you.

TheShodan

iTrader: (14)

I'll need to confirm as the car is in another building right now, but the barb hose from.the VB to the large brake booster T fitting is 7.93mm or 5/16th (shown on the 2nd photo) the T fitting itself I believe it's 3/8ths , but I do believe if there was an adapter male barb fitting between the 3/8ths and 5/16ths. I.know we just used what we had available. But that's the best I can remember without being there

90HFCrX

Makes sense I see it now. So basically find 3/8 T fitting and get a 3/8 npt to 3/8 barb fitting for he vacuum blcok. and run that hose to the 3/8 T fitting to tap into the vacuumm source. Thanks shodan. One step closer.

TheShodan

iTrader: (14)

My pleasure. I may have to make another write up about brake booster adapters so it can be used as a proper vacuum source for a vacuum.block, wastegate, BOV, 3 port solenoids, etc

Txdragon

Certainly relative to the topic.. I mounted a vacuum block once before. I used the brake booster source that I tee'd my boost gauge from, so a good source.. After all was said and done, I had a pretty rowdy surging idle. All barbs used were connected well, the couple that were not were tightly capped. No problem before it.. I removed the block and put it all back as it was and no more hunt.. What went wrong?