With all due respect to the excellent work you are doing on many many subjects here Ross, you have proven to be wrong on the VNT, from the valves to the DGBS. I measured what the latter does, since I bought one too, following your track(s). And despite the fact that I explained in details how any VNT must be managed to provide their best efficiency, and why DGBS was doing worst than just two 5$ needles, you have kept pushing a simple dual valve arrangement. It is just sad for many misled members.
If anybody reading these lines want nevertheless to get more from their Patrol and their VNT, without a MB, be prepared to spend time - and some money.
1/ Get a remap to suppress limp, the EGR effect, and reduce a bit the AFR. You will get more power at higher Revs, but little more down low initially.
Then, "adapt" your ECU ( the only one who keeps the vanes more or less mid-open most of the time, but you don't have a stock Patrol anymore so the ECU vanes management needs to be 'complemented') by doing this in ADDITION to what your ECU does with the Solenoid :
2/ Add a needle to adapt (reduce a little bit) the initial spool up, to compensate for
- an EGR blocked
- a wider diameter inlet
- a 3" exhaust
in other terms, modifiy the initial spool-up to adapt it to your Patrol configuration
Needle to be installed between fresh air and the actuator hose. almost closed initially.
AND
3/ add a dawes between a boost line and your actuator hose, followed (ie in serie) by another needle, almost closed too.
This dawes (to open as early as 4 to 5 psi !!!! ), and the following needle (almost closed initially), will add this little extra positive flow to get the vanes to open a little bit more with Revs and TPS going up compared to what your ECU does, to compensate for the extra exhaust gaz and/or less back pressure and keep boost under control whilst maximizing the airflow.
By tuning this arrangement little by little, and 'in the dark' since you will not have all the tools which would speed up the process, by keeping an eye on your boost and MAF values, you will be able to improve your airflow and increase your torque and driveability.
It won't be perfect, but much much better than any other arrangement (apart from MB - of course).
I am out of this thread now. I did my best to explain and educate but ma patience has now reached its limits. One does not force a donkey which is not thirsty to drink. The most thirsty have been taken care of. I will continue to support them as I always did.
Good luck to all others.
