Pcm Control on big turbo - SRT Forums

**04blusrt_4** · 04-08-2009, 01:18 PM

I am going to be upgrading pretty soon to a big turbo / external wga setup, but would love to get my SCT controlling things.

Can you guys point me in the right direction with what I should adjust? How should I hook up the selenoid to the wga?

Seems like I will have to raise the dutycycle up, say maybe 50% to start with, considering I will be using a 14# spring in the wga.

julius717 · 04-08-2009, 01:22 PM

id go hit up the SCTwiki . do you have a PRP sct or just the handheld?

**04blusrt_4** · 04-08-2009, 01:32 PM

PRP, and the wiki has nothing for controlling an external wastegate.

Seems logical that i would run a line from the turbo to the side / bottom of the wga, and then a line from the selenoid to the top of the wga. I would then have to decrease the duty cycle from stock (maybe level it out?) as to keep the selenoid open, since a higher duty cycle means less boost will be supplied to the top of the wga, by lowering it I will increase the boost, which means the effective spring rate of the wga will go up, which means I will continue to see more boost.

or do I just hook a like from the selenoid to the bottom of the wga, and it will function like a regular boost controller? Seems to me like this way is easiest to control, but the max i might be able to run is spring pressure boost (ie 8 or 14psi).

HELP?!

SRT-What? · 04-08-2009, 06:56 PM

People with DS seems to be able to control the boost at higher level with upgraded solenoids. I don't know if this is the reason why so many people tried without sucess and abandoned.

I'm gonna try to find more info, but if it is the case, then I'm going to buy this :
https://www.201motorsports.com/produ...cat=114&page=1

edit: what do you guys think of this :IEBC

nemiro · 04-08-2009, 08:47 PM

You shouldn't need different solenoid. I have tuned several externally gated cars without issue. Getting the duty cycle tables in the ballpark is the key, as well as controlling the modifier tables to DC and adaptives. It all works hand in hand.

moreause · 04-08-2009, 10:06 PM

you have to use the oem configuartion on th WG solenoid
so you put the wg hose on the bottom of the WG

if you put pressure on another port on the stock solenoid it will no be able to close at higner psi..

some just play with the desired torque table...increase a small amount at the time
and fine tune with duty cycle afterworth

**tgspeedracer** · 04-12-2009, 04:33 PM

Quote: Originally Posted by nemiro

You shouldn't need different solenoid. I have tuned several externally gated cars without issue. Getting the duty cycle tables in the ballpark is the key, as well as controlling the modifier tables to DC and adaptives. It all works hand in hand.

How much boost though? I need 35+

**04blusrt_4** · 04-13-2009, 07:23 AM

Quote: Originally Posted by moreause

you have to use the oem configuartion on th WG solenoid
so you put the wg hose on the bottom of the WG

if you put pressure on another port on the stock solenoid it will no be able to close at higner psi..

some just play with the desired torque table...increase a small amount at the time
and fine tune with duty cycle afterworth

I didnt mean changing the in/out of the stock selenoid, I mean of the two ports on the external wga itself, how should I put the boost signal.

With a MBC, you run one line direct from the turbo to the bottom / side of the wga, then another direct line from the turbo to a mbc, then to the top of the wga port.

So to me, to make this function as a boost controller, I should only change the line going to the top of the wga, and put in its place the line coming off the output of the selenoid.

nemiro · 04-13-2009, 09:57 AM

Hook it to whichever port opens the WG when pressure is applied.

**04blusrt_4** · 04-13-2009, 10:06 AM

Quote: Originally Posted by nemiro

Hook it to whichever port opens the WG when pressure is applied.

Ok thanks Neil

Do you have any other advice for me regarding getting the DC table and adaptives in the ballpark to get me started? Working with a S2 basecode.

nemiro · 04-13-2009, 11:27 AM

Observe, record, and rebuild the table with realistic DCs from what the PCM is actually adjusting to. Then it does not have to guess as much in the future.

**04blusrt_4** · 06-04-2009, 09:19 AM

Ok guys, I am ready to take the plunge on this and switch to PCM control.

I reread what everyone told me, but I guess with my anxiety over running such a large turbo / stock block, I dont want any MAJOR issues the first time I go WOT. a 30psi spike will blow these pistons to the moon

.

Can you guys tell me a good starting point on how to modify my S3 wga DC table, desired torque, and adaptives? I am assuming I have to lower the DC table down, quite a bit, but just how much? Should I make it flatter as far as curve?

Any screen shots of a DC table that has worked on a 14psi spring external wga?

**04blusrt_4** · 06-05-2009, 08:09 AM

nada huh? I know you guys will tell me its trial and error, but if someone has actually gotten it within the ball park, I would like to see your DC table and commanded torque.

JANNETTYRACING · 06-12-2009, 07:33 AM

Quote: Originally Posted by 04blusrt_4

nada huh? I know you guys will tell me its trial and error, but if someone has actually gotten it within the ball park, I would like to see your DC table and commanded torque.

The reason no one is speaking is because it not that cut and dry.

I suggest, return you desired torque tables to stock, as a starting point so you don't hurt anything, Log your duty cycle compare to boost, the adjust till you get what you want.

Should take about a Week LOL!

**04blusrt_4** · 06-15-2009, 04:22 PM

Thanks Ted, figured so much.

I guess i just want to be sure, the duty cycles and configurations. I am going to assume the selenoid is normally closed (meaning it passes boost through to the wga) so at 0% duty cycle, you are running off spring weight boost, and at 100% or higher, you are basically completely closed off and the wastegate is seeing zero boost, right?