Agreed..I am trying to do this with the existing WG. Hence the new control and PWM method.
Sox

I don't know what that means but what I'm saying is that the ign might need to be more retarded at this higher boost level for the same RPM vs WOT to reduce the chance of knock occurring.

Mike G.

sox, i have heard and read many have tried to control the factory single-port wastegate at higher boost levels and have either given up or converted to a dual-port wastegate. i believe the factory wastegate is mechanically incapable of providing the type of fine control you're seeking, regardless of how quickly/accurately you can control the cycle valve.

the solution for me was to go with a dual-port wastegate and an aftermarket solenoid (more accurate/faster than the factory CV) to control boost better.

i hope you succeed but hate to see you waste your time.

I think I understand what you are asking...The ignition retard vs boost and throttle position will change. It will move 3 psi higher, or pressure related retard will happen latter. I don't know if this is enough to cause knock that the knock sensor driven retard will not be able to overcome. Will monitor and report.
Sox

I am using a new PWM controllable solenoid instead of the factory CV, see my post in KLR part 2. As to the WG being unsuitable for more precise control, I don't see why a pressure/spring combination could not achieve better control. Will find out....being retired has it's advantages :)
Sox

Stolen form another site :D

http://forums.pelicanparts.com/uploa...1600275093.jpg


Mike G.

lindsey is a great knowledgeable guy with great tech articles, a lot are geared towards selling more products and providing product-specific information. as such, he only mentions in passing the dual-port dual-solenoid solution which provides the best boost control. all three examples show what's known as a two or three-port boost controller and leaves out the critical fourth (and best) configuration which uses a four-port boost controller that takes advantage of a dual-port wastegate. a manual boost controller can not operate as a 4-port controller because it requires constant variable on-the-fly adjustments, so you must get an electronic boost controller to take advantage of a dual-port wastegate.

honestly if anyone is going to use one of those three examples (with a manual boost controller!) they are wasting money buying a dual-port wastegate.

more details here:
https://dsportmag.com/the-tech/education/science-boost-part-1-solenoids/5/

and here is an example that takes advantage of a dual-port wg:
https://tier1motorsports.com/collections/mac-control-solenoids/products/mac-4-port-boost-control-solenoid-valve-for-dual-port-wastegate-46a-aa1-jdba-1ba

edit: a quick search on lindsey doesn't turn up any electronic boost controller so it looks like they only sell manual controllers, which explains why they only show the three boost control configuration examples and ignore the fourth.

here is the fourth and best configuration to control boost. this configuration also allows you to use lower spring pressure so if the controller fails it will default to practically zero boost, providing an additional failsafe against damage.

note the 951 factory cripple mode still gives some boost because it's a single-port and relies on higher spring pressure. increasing the factory spring pressure increases cripple mode boost and bypasses the failsafe.

http://forums.pelicanparts.com/uploa...1600357241.JPG
http://forums.pelicanparts.com/uploa...1600357241.JPG

Nize the 4 port you have posted above seems to be a on/off system...I am looking for proportional control in my solenoid.
if that is a proportional control solenoid can you post a part number ?
Thanks Sox

Ignore Nize..should have followed the links above.
Sox

I think its one of these guys

https://www.ebay.com/itm/NEW-MAC-4-PORT-BOOST-CONTROL-SOLENOID-VALVE-SENSOR-turbosmart-haltech-aem-apexi-/322993893903

Mike G.

Run with new KLR control system....no tweaking yet. WG is still orignal, no CV.
Sox

http://forums.pelicanparts.com/uploa...1600381574.jpg

Pic of the gauges
Sox

http://forums.pelicanparts.com/uploa...1600381810.jpg

just to clarify, the solenoid is on/off but cycles between on/off quickly, and controlling the cycle rate/pulse is how you control boost proportionally. :) this is the advantage over a manual boost controller.

trivia: the 951 factory cycle valve is called a cycle valve because that's exactly what it does. :)

Thanks Mike.
Sox

Nize, Mike et all would y'all go and look at my post in the KLR part2 and opine?
Thanks
SOx

So after doing the characterization of the stock WG and it's control, next was to to do a dual port with a 4 way solenoid control valve.
I have a Tial I am playing with but decided to see if a stock WG could be modified to become a 2 port WG. Much easier to install and no modification/fabrication to the exhaust system.
Short answer is not really....
First I welded the 4 vent holes in the stock WG. Then I put a crush washer to prevent leaks from the top chamber when it is reverse pressurized. Finally I put a 1/8 inch npt 18 barb into the side to introduce air into the bottom part of the WG to hold it closed against the exhaust pressure.
See pics.

http://forums.pelicanparts.com/uploa...1603211629.jpg

The copper crush washer did not work, it leaked as it was not large enough.

http://forums.pelicanparts.com/uploa...1603211752.jpg

Th aluminum crush washer worked to seal the chamber, and it held pressure in both chambers.

http://forums.pelicanparts.com/uploa...1603211853.jpg

Barb installed, notice the welds for the vent holes.

http://forums.pelicanparts.com/uploa...1603211964.jpg

So here is the problem, the piston that moves up and down inside the the WG,s body runs flush with the walls. So any protrusion into the chamber, like the threaded end of the barb interferes with the motion of the piston.
It may be possible to install a smaller barb into one of the vent holes, but did not look very feasible.
So chalk it up to a learning experience.
Sox

This is where the Tial 46 is ideal, except for the price!!! $500!!

Mike G.

sox; it looks like you have a tial wg sitting on your bench, but you're trying to frankenstein the stock wg? :) why don't you just use the tial!?!?

also, don't feel bad about failing to frankenstein the stock wg into a dual-port, many have already tried and failed, which is why the tial wg is the solution.

lindsey has a successful halfway-stock dual-port conversion but it costs almost as much as a tial:

https://www.lindseyracing.com/mm5/gr...-951-WG-1d.jpg

Nize cause it's more fun :)
Sox

also, make sure you don't get a counterfeit tial!
TiAL Sport - Spotting a Counterfeit TiAL

fake vs real how-to:
https://www.youtube.com/watch?v=__Jzk0XXvr4

fake vs real teardown:
https://www.youtube.com/watch?v=2nOPLxln5Ec