boost controllers

So I just took the car for its very first test drive. I took it around the estate nice and slow and everything seemed spot on. So I reved it a little bit to see how its boosting........
I havnt fitted the new boost gauge yet but the standard one went straight past the +0.7 Which kind of scared me a bit because I have wound the boost gauge closed until I get it on the rolling road. Am i right in thinking this should make it boost less than standard?

http://www.ebay.co.uk/itm/Manual-Boost-Controller-MBC-Tee-Valve-Kit-For-Nissan-Sunny-Pulsar-GTir-Turbo-/221028389257?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item3376519189#ht_1502wt_881
I fitted one of these but have since heard nothing but horror stories about them

The car came with one of these

https://www.youtube.com/watch?v=GrCQPiiUjZ0&feature=related

but it wasnt set up properly and caused it the blow up.
Im lost with what i should do regarding what boost controller to use and weather the stock boost gauge should do that with the adjuster on the manual controller closed.

How did you plumb the new manual controller in ? Id plumb in the boost gauge tbh atleast you know what your boosting and if you have the thing shut off then it should be boosting at stock levels or around that point so should whoop off the gauge ?????

I thought if you closed the manual boost right up you get maximum boost!! Close it off and the wastegate never opens.. Or am i talking b***cks.

johnboy wrote:I thought if you closed the manual boost right up you get maximum boost!! Close it off and the wastegate never opens.. Or am i talking b***cks.

Thats what i thought...

DONT USE A BLEED VALVE

There the easyest way to blow the thing to bits as they are unreliable as they just bleed of to atmosphere.

Either go for a dawes devise, they look like a bleed valve but work of a ball & spring & only open when target boost preasure is reached, or something like that but they dont fail like an atmospheric bleed valve will!

Or go for an electronic boost controller like an, apexi avcr or a blitz, etc

I think it works exactly the same way as a tap as in opening it (anti clockwise) allows the the boost to be bled out of the fitting then winding it in closes the valve(clockwise) as said above not a very stable way of doing it .

If you don't want to run more than standard boost, take the bleed valve off and conect the pipes back up together and you should only get 0.7bar.

If you are getting more after that then something is wrong somewhere!

1 bar loop is accurate and will not spike
its a dangerous game with bleed valve especially if you dont have an aftermarket gauge fitted to monitor boost

Ok so I just quickly fitted an aftermarket boost gauge and refitted the standard boost controller without the one bar loop and the gauge is saying its boosting at 1.2 bar. How is this?

pulsar_stu wrote:If you don't want to run more than standard boost, take the bleed valve off and conect the pipes back up together and you should only get 0.7bar.

If you are getting more after that then something is wrong somewhere!

Remember that the original pipe that attaches to the manifold for boost control has a restrictor in it which sets the 0.7 bar boost. This is quite often the first bit of pipe that gets thrown away by modifiers.

btw what's a 1 bar loop ??

1 bar loop is when you plumb the piping straight to the actuator and down to the air intake taking the standard actuator out of the equasion.
The boost runs off the torbo actuator which is a 1bar actuator.

what turbo do you have alex?

Have you a topmount intercooler or front mount?

Sometimes when running a topmount. People get one of the vacume pipes trapped under it and this causes the boost to hike itself! I've had it at 1.4bar before lol

Check all the piping for any splits or not clamped properly, the boost presure might be bleeding off somewhere.

sorry stu but your not quite right there....the stock actuator is 0.5bar, the boost control solenoid with restrictor takes it to 0.7bar

with the 1 bar loop as stu said you bleed off boost back into induction pipe which should then hold stable 1 bar boost.

so you either have a vacuum leak somewhere or the actuator is an aftermarket one or been adjusted to run at 1.2 bar
if you come straight off nipple for throttle bodies direct to actuator it should only hit 0.5 bar with no restrictor in the pipe

I've tried every combination and got nowhere today. Almost got caught by the police speeding down the road because I was to busy looking at the boost gauge and didn't see them coming the other way. So I called it a day. I'll have another look tomorrow with a fresh head and try going straight from the throttle body nipple to the actuator to see if it runs 0.5 bar like bob said.
Stu the turbo is stock, I thought it over boosted because I put a bleed valve on there but it was still boosting at 1.2 with the std one

Also im beginning to think im missing the restricted pipe

The OEM restricted pipe is about 8" long and usually has a green ring painted round it near one end to mark where the restrictor is.

Is this the metal pipe that is routed through the middle of the top mount and the bracket? if so I still have it.

No the restrictor pipe is a rubber pipe which originally went from the inlet manifold to a short bit of metal pipe attached to the underside of the intercooler. From the intercooler it then goes back to another rubber pipe where it splits to go to the wastegate and boost solenoid.
Why Nissan did it this way is a bit strange but it means that when people put in boost controllers or move the intercooler to the front this bit of pipe gets lost.

You can use a welding tip to replace the restrictor cant remember what size tip you use though

Nissan main dealer £50,000000000000 plus vat + explaining it for a hour and source out part numbers yourself = priceless

Too true.

Thank to to everyone for your help and advice. I've just figured it out and am now running a steady one bar Turns out the standard boost solenoid was faulty.

Lol happy days then im suprised you still had it if you had a boost controller plumbed in

bob the brain strikes again
if my head gets any bigger il need a bigger car
glad it all worked once boost controller was out the equasion alex

It just goes to show not everyone in essex is thick lol