burgers22

Thanks Razorlab, as this was the first run with the 3 port I erred on the conservative side, I've now added 5% WGD to match the target boost and WGD better.

ON the installation side I rubber mounted the GM BCS and used two 20ohm 0.6 watt resistors in parallel as these were easier to source than a single 10ohm item.

MB

fostytou

iTrader: (15)

My only issue with this would be that there is not much holding those connectors on, certainly no lock. It seems to get this method to work properly you need to plumb the normally connected port of the BCS to the WGA, so if one of these connectors fell off you would essentially be freewheeling/running without a WGA.

EVOlutionary

iTrader: (38)

I ordered the P/N stated in the first post in this thread but my unit looks different than the one pictured here. The one I received has a little filter on the bottom port on the left hand side (as shown in the picture above). Is that correct? Do I just remove the foam filter?

Thanks!

Gpunkt

yep, is correct.

mplspilot

iTrader: (7)

Take off the filter. You can either leave the port open and unconnected to anything for it to vent air to atmosphere or route a line from it into your intake.

EVOlutionary

iTrader: (38)

Thanks!

wrcwannabe

iTrader: (1)

This is metered air and needs to go back into the turbo inlet, IIRC. Rule of thumb on MAF based systems = never VTA any metered air. Even slight amounts could cause drivability issues.

Milburn

mplspilot

iTrader: (7)

I believe its a non factor. MBC's vent to atmosphere as well AFAIK.

MR Turco

iTrader: (16)

MBCs sit between a boost/vacuum source and the wastegate. There should be no venting to atmosphere for a MBC.

TeStUdO

iTrader: (6)

You may notice that many ball-and-spring type MBCs have, by design, a small hole… either in the case, or in one of its "barbs" or "nipples". Such a hole is typically on the "Wastegate side", so when boost is building on the charged-air side of the MBC, no pressure can go out that hole until after the desired boost level is achieved and the spring-loaded ball is pushed out of its seat. Then the boost signal rushes past the ball on its way to the Wastegate Actuator. The reason for that hole is to allow the "column" of charged air, or "boost signal", to drain or "bleed" out of the hose that sent the signal to the Wastegate Actuator. Without that hole, the charged air in the hose to the Wastegate Actuator would tend to "get trapped" and would slow the proper closing of the Wastegate. Technically, it is an inefficiency to allow some boost to escape, but it is a very small inefficiency that has a good trade-off.

mrfred

iTrader: (50)

A small amount of VTA hasn't caused any drivability issues on my boost control setup that I've been running for over a year.

fostytou

iTrader: (15)

I'm not sure if interforum linking is 'ok', so please let me know if I need to remove this...

Here is the connector for the stock BCS (replace xx with tt, copy, paste)
hxxp://www.norcalevo.net/forum/index.php/topic,23834.0.html

I think by aircon he is referring to air conditioning... I'll have to look at my car when I get out of work.

copy of the images here: http://thefrost.net/randomfiles/rand...ess_switch.JPG

I called GST motorsports but they haven't gotten back to me yet about their custom molded plug.
The plug does exist on our evos, and to the best of my ability to see those pictures it looks to have the same part number as the classic one. The part number reads like this:
C029A
7H05

Edit, rather than keep updating both of these I'm posting updates here: https://www.evolutionm.net/forums/sh...6&postcount=52 (and posts following that)

fostytou

iTrader: (15)

Just did a confirmation of Mr Evo IX's AEM (tru-boost, but its the same as the seperately purchased solenoid) and yes, the stocker was about 32 ohm, tru boost was about 12-14 ohm. I tried resistors in series (on on each side of the leads to the solenoid) which totalled about 32 ohm and it just wasn't enough power to move the solenoid. Spring pressure every try.

So, if you are using the AEM solenoid you are leaving the ability to send a bit more power to it, but that doesn't necessarily mean that you will be over-amping anything in your ECU. After putting in the JDM MAP I'm kind of surprised how high my spike was and how much duty cycle I need to keep the stock turbo pumping!

Pics of the connector off an AC line pressure connector I used for PNP on the BCS being hacked are here: http://thefrost.net/gallery/main.php?g2_itemId=4019

You don't really need to remove as much material as I did... and frankly you could probably get away with cutting the plastic instead of slicing the metal fitting in half. I just cut the fitting in half with a dremel cutting wheel and then split it with a pair of needle nose pliers. Then I worked out all of the inner bits with a combination of needle nose and eyeglass screwdrivers. Interestingly simple device though!

fostytou

iTrader: (15)

OK, stupid question for someone who didn't pay attention well enough to his bad electronics teacher:

I think when you use 2x10ohm 1w resistors you are dropping the voltage to ~6v at the solenoid. Does that mean we are dropping the voltage to ~9 volts with 1? It seemed like the AEM solenoid is acting a little funny (boost will go up 5psi sometimes with 1% more duty cycle) and I was wondering if it was related to it struggling for power...

matt55

iTrader: (12)

I ordered the GM 3 port , Ive read this whole thread 2-3 times . But some of it over me .
Could someone tell me if I used this map listed above would that get me "close" and if change is needed I should change the '''Max Wastegate duty..." to get -/+ psi @ that RPM . I would like to hit 24psi @peak and hold it longer than my mbc can (MBC is droping to 17-18@ 7.2k)