[hubbell]

i have a SC on my vr6....as i understood it i should be able to tap my vac line for the boost gauge at the FPR with a "T" fitting...i did this and the gauge would not read boost only vac....i then moved the tap in place for the vac line to right after the SC outlet and now the gauge reads boost only....so what am i doing wrong here? thanks, rick
btw its a stewart warner boost gauge from 42 draft designs and it does read both vac and boost in case someone thinks im that dumb....thanks for the help....

 

[Hugh Gordon]

Re: ive searched but im having trouble with my boost gauge (hubbell)

I just experienced the same thing today on my friend's car. He put a z-engineering kit on, and the gauge would only read 1psi when tee'd into the FPR, moved it to the intake side and saw about 4psi. I really can't think of any reason it would act like that.

 

[hubbell]

Re: ive searched but im having trouble with my boost gauge (hubbell)

was just looking at 42 draft designs web site and they said their T fitting has a restrictor in it...so in addition to my previous question im also wondering about my DV....i was using the FPR tap for the vac line for the DV...will this restriced T fitting mess that up? what should i do here...i thought the idea was to get vac from the FPR vac line for both the DV and the boost gauge...im just not sure how to make it work with a boost gauge restrictor T fitting ad a DV that doesnt need a restrictor...thanks for the help...

 

[BoostedOne]

The reason you only saw vac the first time is because you were downstream of a check valve.
The reason you only saw boost the second time is because in order to see vacuum you need to be downstream of the throttle body.
I cant think of any good ports in a VR manifold to tap into. You have two choices though.
First, follow the plastic vacuum line off the manifold to the brake booster. If you have ABS, at some point the plastic ends, and there is a little bit of rubber hose, then a plastic(usually blue and black) thing then the hose continues on. The blue and black plastic thing is the check valve.
Simply unplug the check valve and put your tee in the end of the hose(from the engine), then run one of the other connections of the tee to the vavle, and the remaining leg of the tee to the gauge/diverter valve.
Or you can remove the intake manifold, drill a hole in it, and tap it for 1/8" NPT, and put a pipe thread to barb fitting in the hole. Thats what I do.
I DO NOT like to use the fuel pressure regulator line for gauges and blow off valves, because it tends to dampen the vacuum signal to the regulator.


Modified by BoostedOne at 3:18 AM 9-11-2005

 

[vr6chris]

Re: (BoostedOne)

On a vr, just tap into the brake booster hose. There are a couple of nipples on that hose that are perfect for use of a boost gauge. http://****************.com/smile/emthup.gif


Modified by vr6chris at 3:23 AM 9-11-2005

 

[hubbell]

Re: (vr6chris)

should i use the supplied restrictor T fitting?

 

[hubbell]

Re: ive searched but im having trouble with my boost gauge (Hugh Gordon)

and why is it restricted...i dont get that either....

 

[hubbell]

Re: ive searched but im having trouble with my boost gauge (hubbell)

it only did vac off the large manifold line....still wondering if there is a difference on where the gauge should go considering it is a SC not turbo....i did not use the restrictor this time and still only vac....please help... http://****************.com/smile/emthup.gif

 

[Kor]

Re: ive searched but im having trouble with my boost gauge (hubbell)

Quote, originally posted by hubbell »

and why is it restricted...i dont get that either....

42dd puts a restrictor in the line to the boost gauge to "smoothen" out the way the needle moves. Since it is a mechanical gauge, it can vibrate or bounce a little as the boost in the line changes. Some people get "buzzing sounds" from the gauge if there is no restrictor.

 

[2kjettaguy]

Re: ive searched but im having trouble with my boost gauge (Kor)

The T-Fitting has a built in restrictor to prevent buzzing. The T-fitting needs to be installed as so:

Basically, the center barb must feed the boost gauge. If you had it in another orientation it's possible that could have affected your readings. The FPR location should be ideal. I am not sure why that location didn't yield good results for you.
Evan

 

[BoostedOne]

Re: ive searched but im having trouble with my boost gauge (Kor)

Heh, why is it when VW guys turbo a car all of a sudden they need restrictors everywhere that other people dont?

You guys are sticking restrictors in places I never even considered.

 

[hubbell]

Re: ive searched but im having trouble with my boost gauge (2kjettaguy)

yeah ive seen that pic before and it was oriented properly....still not sure whats up here...

 

[2kjettaguy]

Re: ive searched but im having trouble with my boost gauge (BoostedOne)

Quote, originally posted by BoostedOne »

Heh, why is it when VW guys turbo a car all of a sudden they need restrictors everywhere that other people dont? You guys are sticking restrictors in places I never even considered.

It's not just VWs, but for some reason the VWs buzz the hell out of some boost gauges. All the gauges I have ever worked with have buzzed on a 1.8t. I don't know if it's the small intake manifold, the small turbo, or all the extra crap in their system but the airstream going to the gauge is less like pressurized air and more like a bumblebee fart.
Most VR6's don't buzz the gauges, so you should be fine without the restrictor. Most 2.0's don't buzz them either. Mainly the 1.8t...
I'd say try a restrictor-less T. I can even send you one if you'd like.
Evan

 

[BoostedOne]

Weird. Never working on a 1.8T is probably why I never seen this then. Well, not a 20V 1.8T anyhow

 

[hubbell]

Re: (BoostedOne)

i appreciate the offer of sending me a new T but i have others....i still dont know why it wont give me both vac and boost on a charger....

 

[2kjettaguy]

Re: (hubbell)

what readings do you see tapped at the FPR with no restrictor?
Evan

 

[2kjettaguy]

Re: (2kjettaguy)

idle, crusing, and full throttle from 2k - redline readings...

 

[hubbell]

Re: (2kjettaguy)

i havent actually gotten to drive the car yet but at idle it is at zero or vac....once i rev the engine a decent amount say to 5K it goes further into vac....i wont get to drive the car until this weekend i guess...still have a few things to button up first...