hi all,
i have a 95 sti with an apexi induction, i have noticed i have no pipe on the bottom of my boost solenoid, isnt there ment to be a restrictor on it and what size does it need to be?
thanks phil.

 

yeah mate there is meant to be a pill in it, im sure someone on here will be able to tell you the correct size for your motor.

 

Yeah there should be a restrictor pill in that pipe and... er, it needs to be present lol:-



Best to PM JGM to find out correct size.

Are you getting overboost - got a boost gauge?

 

As far as I know the stripe on the pipe (as above) has the restrictor under it, if you pinch with your fingers there it will be hard, if not no restrictor.

 

i am getting spluttering at high revs? as for boost, its about right on the gauge 1.1, it feels like fuel cutting but not sure, whats the pill for exactly?

 

Pegs the max boost to a suitable level for the times when the ECU/BCS decides 100% WGDC is okay to use...

 

well explaned, thanks, so does it suck or needs pressure? and where does the other end connect too?

 

Air gets bled out through it when the BCS is open - it's a solenoid so moves up and down radpidly at a rate dependent/proportional to the amount of WGDC allowed by the ECU. This means that less boost pressure is getting to the w/g and therefore won't overcome the spring's tension and crack the w/g open. So it effectively raises the amount of boost required to do so i.e. turbo boosts for longer/makes more power. It's effectively a glorified, ECU-governed active bleed valve.

The other end of that vac pipe is 'supposed' to go to the little port in the std airbox, but leaving it hanging free in the bay is okay, as that port is before the MAF so would get accounted for or not, as the case may be (but that's a moot point anyway)...

 

yet another excellent answer, thankyou very much, ive just found a spare pipe with said restrictor, the hole is very small, so i guessing that my spluttering isnt because of the lack of a pill, as mine should boost more than 1.1 with a big hole, unless the gauge is s**t and its boosting more, it does feel fast untill it splutters?

 

You need to refit that pipe/pill back to the 3-port BCS's bottom vertical port... perhaps perform an ECU reset... and then see how she goes...

After all, that would be putting the car back to std as far as the boost control system goes.........

 

will do it tomorrow and let you know, i do think the gauge is on its way out though, so hopefully it is the pill, thanks very much for your well explaned answers, without knowing i think you have solved another problem i have on another car of mine too, nice one,
all the best, phil.

 

Didn't you fit a ruddy great front mount turbo set-up to your car? I thought it was wagon, no?

Have you got rid of that car for this STi v.2?

 

your right with the big turbo, that was on my impreza based rs200, and ended up rotated instead, ive always had both of these cars for the past 3 years, the rs200 has got a normal turbo engine in for a while as after the stroker rebuild it developed a slight noise, so i pulled it out, good memory though.

 

BTW, the Apexi induction is doing you no favours if it's not been mapped for. The std airbox/panel filter doesn't represent a bottleneck/problem until you're approaching 350bhp odd. Plus that Apexi, if not mapped for, may have thrown the AFR's out of kilter - invariably leaning them out! - not good. Can run the risk of picking up a piston in the bore in this scenario.

Refit a std airbox and a OEM paper, Green or K&N panel filter too...

 

will take a look at that as its not been mapped for any of it, thanks for everything joz8968 ill reply tomorrow with what i find out, thanks again,
phil.