boost tap question (not how to install)

[Munta]

Hi guys... i have finally gone and installed a manual boost tap on the leggy, (cheap $35 off TM)

couple questions

Boost builds and spikes at 1.0bar then settles down to 0.7/0.8bar 1st and 2nd gear... havent had the road space to try 3rd,4th or 5th yet as motorway still busy till later..

is this size spike in pressure usual when upping the boost?
im happy with where it is holding pressure at the moment but a little bit worried bout the spike.
current mods are, piggy back ecu, exhaust, 600x300 i/c, pod filter (i want original filter) and its a manual

any help would be great

[Turbo_Steve]

It depends if you're running it inline with the factory solenoid or just between wastegate and actuator.

To be honest, I'd shy well away from a boost tap, and use a ball spring valve device (Dawes device or similar) as they offer much greater boost stability for very similar money.

Given the results you're getting, however, I'd suggest you need less bleed: it's likely that the size of the spike is actually your "target" boost in a higher gear, and that either the factory solenoid or the vehicles natural boost charecteristics in early gears are limiting it to 0.8.

I would probably advise against using a bleed valve inline with the ECU control, as it's likely to be all over the place whilst the ECU tries to compensate for the bleed valve.

[Munta]

Given the results you're getting, however, I'd suggest you need less bleed: it's likely that the size of the spike is actually your "target" boost in a higher gear, and that either the factory solenoid or the vehicles natural boost charecteristics in early gears are limiting it to 0.8.


just got home from a test drive on the motorway and what you have said is right... hitting 0.9 bar in 3rd, 4th and 5 which was my target, and its not spiking and holding very solid thru the revs.

feels alot better to drive as well.
thanks for the reply
Very happy with results :p