telemekas

Yes

The early secondary turbos VF14 and VF17 are the only ones with wastegates. With further improvement and simplification of the TT sequential system these were made redundant on the later secondary turbos.

Example of AUDM B4 conversion: Using the TT ECU and a greddy profec B spec II boost controller - it made 203kw on 18psi. The single turbo conversion was done on the original B4 motor using the following parts: -standard headers with catless up pipe -VF29 -silicone intake & 'short fat' bit -hyperflow CAI -samco silicone y-pipe -STi TMIC -3" turbo back exhaust

The VF20 is the primary and VF21 the secondary. The earlier models TT had wastegate on the secondary turbo --> VF14 and the VF17 only The secondary turbos VF14 and the VF21 are essentially equal in power no gains from swapping. Both use same size compressor wheel.The turbine wheels are different 5700 vs 4600 but this offset by the turbine A/R, P16 vs P18

I contacted Fortyone.co.nz on 31 August 2011 and was quoted $350 AU delivered. No harness available for my TT and the unit is sent directly to you from Japan.

Pics and details please How much did the butterfly valve cost. what butterfly valve did you use, etc Jun B.L ECV $250 operates via port No:6 solenoid box Similar to this one: http://www.ebay.com.au/itm/400062383069?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649 Replaced the ICV with one these: http://www.aid-inc.com/product_50/check_valve.html

It is in your pic. Follow hose No:5 (the one below No:3 in pic) from the solenoid box.

OK. For tesing only: unplug the vacuum hose that goes to the top of the very large ECV actuator. Plug the hose leave the actuator port open. Go for a drive and note any difference.

No need to start the car, just have ignition on. Run for 60 secs (you will hear the clicking and fans cutting in and out). Ignition off and unplug green connectors. Restart car to charge the vacuum tank. Repeat above.

Connect the two green plugs under the dash and turn the ignition on. This will activate (check and quick clean) the solenoids and fans. Run for one minute (Appprox 60 secs the vacuum storage tank will discharge.This will recharge when you start the car) Do this several times and see if it makes a difference.

Yes.

On the last revision TT the solenoid port No:11 is not used. The one next to it No:12 goes directly to the manifold The bunged port comming off No:12 was for measuring manifold pressure ie boost gauge With the accumulation of dust and oil in the vac lines and actuators over time they become less sensitive/responsive. Time to service/clean the solenoid box.

Removed the ECV and replaced it with vacuum operated butterfly valve (low down in the 2nd turbo dump pipe).

Yes, boost drop off is cut by more than 50% (ie 7psi-->2-3psi)

You will need your existing primary turbo Non-BB VF26. A turbo shop will remove the compressor cover and turbine housing from the BB VF27. The centre section CHRA of the VF27 is then used to replace that of the VF26. These two turbos use the same size wheel sets, so no performance increase. However it will be slightly more responsive as you will now have a unique BB VF26

That in essence is how the Toyota Supra Sequential Twin Turbo IACV change over operated. (a small passive reed valve in conjunction with the butterfly valve) The Subaru TT can be improved by replacing the IACV with a passive one way check valve. This allows you to remove the Supercharger pressure relief valve. However for optimization the ECV needs to be ported or removed and a new type installed low down in the 2nd turbo dump pipe.

http://www.veloce.pwp.blueyonder.co.uk/Twin%20Turbo%20Operation/ttopprt2.htm

The primary VF26 (RHF4) is a non-Ball Bearing (sleeve) turbo Bearing rebuild kits are available.

Yes. The VF14 has an WG actuator and VF27 does not. Therefore need to block off hose No:8 from the solenoid box.

Block it off.

Bolt of the support bracket for Power steering lines (Pressure and return)

This is a good start: http://www.scoobypedia.co.uk/index.php/Knowledge/ECU http://forums.nasioc.com/forums/showthread.php?t=1410201

Solenoid box Line No:8 connects to the 2nd wastegate actuator See Sequential Turbo diagram on this page: http://www.clubsub.org.nz/forum/index.php/topic,9899.0.html

I pressure tested the ECV using the top positive pressure port. Begins to open at 120 Torr or approx 2.5PSI and fully open at 160 Torr approx 3.5 PSI