Lord Bass

i've got a boost gauge in my 2002 wrx its connected to the dump valve via a tee piece thats got a pin sized hole the the part that goes to the gauge. i got the tee piece with the gauge. anyway when i take my foot off the accelerator pedel the gauge needle moves very slowly back to where it starts is this normal or should it snap back quickly?

Rokay

Clicky

Although not a boost gauge the px gauge shown will give you some idea of needle deflection response.

I guess my boost gauge reacts in a similar manor.

Lord Bass

thanks my response is much slower than that especially on the return. Any idea what could be causing it and what would happen if i used a tee piece with a normal sized hole and not the pin sized one?

jaytc2003

iTrader: (1)

Do you have a vta dv or is it a recirc type? It should move back quickly.
A bigger hole size will certainly help but it seems strange that you have your gauge teed into the dump valve, dont think that would be the ideal place to have it plumbed in. Surely changing gears would cause it to show that you are boosting when you are not. (could very well be wrong here as am quite new to scoob ownership however principals on boost gauges should be similar for all turbo cars)

Rokay

This may help you. Its a guide to fitting gauges. Have a look at the photograghs should give you some idea where you take the boost tapping from.

I have installed Defi D gauges (mechanical) in mine and the tee piece bore is almost the same size as the hose. Thats mechanical.

From the description of your tee piece supplied it sounds like you have an electronic gauge all linked to a control unit via daisy chain connections. Would i be right?

If thats the case then these gauges need to convert the mechanical movement into an electronic signal. Although i haven't actually seen whats supplied with an electronic boost set up i have had a pretty good description explaned to me of what is actually supplied for installation. I do know that the tee piece does have a very small hole, much smaller than the one supplied with mechanical set up.

That aside where you actually take the tappings for any boost indications be it mechanical or electronic are no different.
Do have a look at Stefans site although based on the RB5 there are many similaritys so could be a help to you.

Lord Bass

its a mechanical gauge just the tee piece to the gauge then power for the back light. So you think the suppiled tee piece is wrong? Also should it move if i rev the car when its no moving as it does'nt its a VTA dump valve not a recirulating one.
thanks for the help

jaytc2003

iTrader: (1)

if its plumbed in to the dv feed then its plumbed wrong as you will get a lot of activity between gear changes as this is when your dv gets most of its pressure. There is a vacuum feed on the engine that is the best place for it to be connected. It should move depending on the gauge. Usually the gauge will have negative - nothing - positive. Basically it is measuring vacuum. So with the engine running and idling there will be negative vacuum showing as negative on the gauge, then with prods of the throttle it will move within the negative range (dont think it will go into the postive or above 0 but I could be wrong on that)
The web link above shows you where to plumb it into.

Rokay

Right mate if you say its a mechanical gauge then i'd go for a different tee piece. I think you should be able to get it at the likes of Halfords. Just had a look at a spare one i have here and the bore is about 1/32" dia considerably larger than the one you have at the moment by the sounds of it.

Have a rethink on the connection side of things. I know that Stefens car is a classic and there are differences all be it very small ones. I think if you compare your manifold and the one in the link then you should be able to work out where a connection should be made. See how you get on and keep us informed.

Lord Bass

i had a look at my intake manifold and no place spare to put the vacuum hose its different to the one in stefans pictures. i can't see where else to put it other than where it is any ideas?

Rokay

I would really need to see a picture first. To date i have only installed gauges in classic cars, both mechanical and electronic.
In the meantime if i see a shot of a 02 with a boost gauge installed i'll let you know.

Lord Bass

ok thanks i'm gonna try a different tee piece tomoz i'll let u know how i get on.

Rokay

Ah ha, mate you got a copy of SIDC's TrueGrip mag March 2005?

Page 24 theres an artical on a 02 WRX showing the ins and outs of fitting a boost gauge.

Lord Bass

i haven't..... any chance of scanning it and emailing it to me?

Rokay

I haven't got such facilities i'm affraid what i can do for you is photocopy it and send it on if you like. PM me your address and i'll forward it. I'm not back on shift until Friday morning if you can wait that long.

Lord Bass

thats fine thanks u have PM

Rokay

Address received mate, leave it with me you'll have a copy real soon bud.

The Fixer

LB, bob over if you get chance and Matt or myself will have a quick look for you.

Conrad

Rokay

Now thats an offer you can't refuse. I'll still get you that article though

Lord Bass

Thanks for the offer but i don't get over that way very often

Lord Bass

it was the tee piece one side had a blockage so i replaced it with one that all three holes are the same size and now the gauges reponse is excellent 1 problem. When idleing the needle flickers on the spot like it shivering its fine when driving but shakes like mad when idle any ideas?

thanks for all the help

Plym51

Thats what the restrictor in the tee piece was for, to damp the needle, due to the fluctuations in the inlet manifold.

When i got my boost gauge the tee piece supplied had a little brass restrictor in it. I wasn't very happy with it so i made a new tee piece out of brass and incorporated the little brass restrictor in the new one i made.It works a treat,

cheers Plym 51

Rokay

Just spotted mate that you have had some sort of success. We're getting there. So you have needle fluctuation then.
OK so Plym51 sudjest theres a reason for the needle hole. Makes sense.
You have found out that the neddle hole you originally had/tried was certainly of a size that wasn't helping you. If i where you i'd try opening up the needle hole a tad more but obviously not as much as your new tee piece. Bit of trial and error. See how that goes.

Lord Bass

problem is that the original tee piece had a blockage as well as the needle hole so i replaced it anyone know where i can get a new tee piece? with the needle hole in?

Rokay

So you have up set the original hole then?

Lord Bass

yes coz one side of the tee piece had something stuck inside so was completely blocked so i just replaced the whole thing.

Rokay

LeMans Motorsport

Try the above for a tee piece. Give them a ring there real helpful and know there stuff.

Failing that i guess Halfords, Camberley Auto Factors or a good car accessery would be able to help.

Lord Bass

ok thanks

Lord Bass

finally sorted... it was the blocked tee piece that caused the slow response not the pin hole. I drilled the blockage today and left the pin hole in and its sorted the gauge response it how it should be and the needle does not shake.
The dump valve works much better not too.

Thanks For All The Help

Rokay

Glad you are sorted mate. Job satisfaction.

Lord Bass

yes indeed