Vacuum take off's for BOV, Fuel pressure etc.

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vwfreakster
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Vacuum take off's for BOV, Fuel pressure etc.

Post by vwfreakster » Sun May 01, 2016 3:40 am

Hi

I'm just going through my 2276 FI turbo motor trying to iron out and check some rough running issues. Can anyone confirm that all vacuum ports for the MAP, fuel pressure, BOV and boost gauge should be taken from below the TB butterflies?, my wastegate is plumbed before the TB's. (Can the boost guage (Autometer 3304) before fed from the pressure hat?)

This is my motor:

https://www.youtube.com/watch?v=HTrAo11ZE-Y

Thanks :D

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rubenski
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Re: Vacuum take off's for BOV, Fuel pressure etc.

Post by rubenski » Wed May 04, 2016 11:21 am

My first tought would be below the tb's
My cb blackbox timing control with MAP sensor was connected at the bottom vac port on my dell 36.
Better to be blown than to suck!

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kangaboy
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Re: Vacuum take off's for BOV, Fuel pressure etc.

Post by kangaboy » Tue May 17, 2016 9:37 am

Blow Off Valve, Manifold Air Pressure, Fuel Pressure Regulator, and Boost Gauge are after the butterfly in the manifold. The Wastegate will be before the butterfly in the charge pipe.

Edit: When I was referring to the above items, I was referring to their vacuum lines, not the actual items. (i.e. Blowoff valve is mounted in the charge pipe after the turbo but before the TB butterfly, and the wastegate is mounted in the exhaust prior to the turbo.

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woodsbuggy1
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Re: Vacuum take off's for BOV, Fuel pressure etc.

Post by woodsbuggy1 » Tue May 17, 2016 4:28 pm

All of my reference ports are after the TB, including the wastegate, works well for me. I am not sure how much restriction is created in my intercooler but decided to reference after it to get full WG spring pressure.
Kenric
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Re: Vacuum take off's for BOV, Fuel pressure etc.

Post by kangaboy » Wed May 18, 2016 8:08 am

woodsbuggy1 wrote:All of my reference ports are after the TB, including the wastegate, works well for me. I am not sure how much restriction is created in my intercooler but decided to reference after it to get full WG spring pressure.
Kenric
After doing some research, it seems this is a great debate in multiple boost forums. Long story short, do what ever works. Seems referencing before or after will not blow your motor one way or another, but depending on piping and intercoolers, one way may create a little more lag than the other. So I guess just hook it up which ever way looks cleaner or is easier.

Just referencing this site for my source:
http://ls1tech.com/forums/forced-induct ... nswer.html

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woodsbuggy1
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Re: Vacuum take off's for BOV, Fuel pressure etc.

Post by woodsbuggy1 » Wed May 18, 2016 9:10 pm

Thanks for doing the research, I am far from being an expert in forced induction. I just did what made sense to me. I have trouble understanding how the WG reference point would have any effect on how the turbo spools but who knows, maybe the reference point does effect exhaust temp and velocity. Please understand I am not at all trying to start anything, just trying to understand different schools of thought. The one thing that I do know is that a boosted engine is much more fun than NA :D :D .
Kenric
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Re: Vacuum take off's for BOV, Fuel pressure etc.

Post by kangaboy » Thu May 19, 2016 8:21 am

Haha, I wasn't questioning your setup or reasoning at all. Hell, I haven't even finished building my setup yet. I had no idea one way or another, and was just going by some google images that I saw. After reading a few threads, I have a better understanding, but it still seems there is great debate on which one is "correct". I'm just going to take the easy way out and reference from the turbo housing, because that's where the internal wastegate vac port is.

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woodsbuggy1
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Re: Vacuum take off's for BOV, Fuel pressure etc.

Post by woodsbuggy1 » Thu May 19, 2016 8:27 pm

No worries, I am not saying that I am right at all I just have a hard time believing that it matters much, thanks again for sharing I have lots to learn :D .
Kenric
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richardcraineum
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Re: Vacuum take off's for BOV, Fuel pressure etc.

Post by richardcraineum » Mon Jul 25, 2016 8:15 pm

fpr should not be after tb or butterflies as it will pull a vacuum on fpr when throttle plate closes and can drop fuel pressure ( opposite of adding boost pressure ), unless u have a one way valve inline
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Clonebug
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Re: Vacuum take off's for BOV, Fuel pressure etc.

Post by Clonebug » Mon Jul 25, 2016 9:39 pm

My fpr has been on the vacuum side of the TB for 3 years without an issue.
I run the stock German Beetle FPR and that's how they were plumbed too.
Stripped66 wrote:The point wasn't to argue air temps with the current world record holder, but to dispel the claim that the K03 is wrapped up at 150 HP. It's not.

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Re: Vacuum take off's for BOV, Fuel pressure etc.

Post by kangaboy » Tue Jul 26, 2016 7:47 am

Clonebug wrote:My fpr has been on the vacuum side of the TB for 3 years without an issue.
I run the stock German Beetle FPR and that's how they were plumbed too.
I have mine plumbed the same way. The only thing I have before my throttle body right now is the wastegate line.

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Re: Vacuum take off's for BOV, Fuel pressure etc.

Post by richardcraineum » Sat Aug 06, 2016 8:54 pm

stock german fpr? efi? and just cause u shouldnt doesnt mean it wont work, hell ive done alot of poop i shouldnt but it still works great. but , just as boost pressure raises fuel pressure in an adjustable fpr vacuum should lower the fuel pressure. may not matter since the throttle has closed idk but i just dont route em that way to be on the safe side
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Re: Vacuum take off's for BOV, Fuel pressure etc.

Post by vwfreakster » Tue Sep 12, 2017 6:15 am

Thanks for the comments all.

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Re: Vacuum take off's for BOV, Fuel pressure etc.

Post by seabeebuggy » Mon Sep 18, 2017 11:40 pm

I tapped each intake at the base with a 3/8'' barbed fitting both sides. They are connected with a single 3/8" line off that line I feed everything except the WG. I get a very strong signal and it is correct every time.

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