boost on smic

[DJ Cool Breeze]

can i dial it up to 10psi??????i keep hearing conflicting replies to this question...is anyone here hitting 10psi with smic? if so any problems yet?

[srpowered240sx]

go for it. i did it from time to time before the fmic. i wouldnt run it all day, but if you have a controller, you can safely turn it up that high. make sure you at least have a hole in your bumper for some more air though.

[SpeedRacer1]

Honostly the stock S13 SR actually runs at about 11 psi. 99% of people on this board think otherwise but 99% of the people on this board tossed the stock boost pressure solenoid during the swap. Tossing this unit limits the boost to 7 psi. Which is why everyone says stock is 7 psi. I have this unit on my car and it runs 11 psi when connected, 7 when its not connected, or the ecu is in limp mode. I have tested this on multiple cars with the exact same results.

So the smic can handle 10 psi fine because it was designed for over 10 psi stock.

[Jasong]

Mine runs 10 to 11 stock also.

[silverarrow27]

Good to know stock boost is 10-11 psi with selenoid. Didn't know that after all these yrs! But I like 7 psi...saves me gas and tires.

[TchouikoS13]

Honostly the stock S13 SR actually runs at about 11 psi. 99% of people on this board think otherwise but 99% of the people on this board tossed the stock boost pressure solenoid during the swap. Tossing this unit limits the boost to 7 psi. Which is why everyone says stock is 7 psi. I have this unit on my car and it runs 11 psi when connected, 7 when its not connected, or the ecu is in limp mode. I have tested this on multiple cars with the exact same results.

So the smic can handle 10 psi fine because it was designed for over 10 psi stock.

Guess you learn something new every day huh... Well i was curious if you, or anyone else, happen to have pictures of this boost pressure solenoid? And some general info about it.

[Geno750]

Guess you learn something new every day huh... Well i was curious if you, or anyone else, happen to have pictures of this boost pressure solenoid? And some general info about it.

I can snap some pics of the one that came with my swap. I'm ditching it for my AVC-R

[SpeedRacer1]

It usually comes attached to the igniter chip plate. It is gold while the EGR piece is green plastic. You can toss the EGR part but the boost control solenoid is useful for more boost. Also later on some aftermarket ECU's, like the Power FC, can plug into directly into the stock boost control solenoid to control boost like a boost controller.

Boost control solenoid is on the left, if you need instructions on how to run the vac lines let me know.

[kamikazestorm420]

where does the ignitor bolt up? can you show me a picture?

thanks in advance

[IDriveFords]

Hey speed, can you post the diagram for how to route the vacum lines with that solenoid. Thnx

[adrianfromthecastle]

hope your still not running your stock recirculation valve..

[SpeedRacer1]

where does the ignitor bolt up? can you show me a picture?

thanks in advance

I am not sure exactly what your asking, on the US car or JDM car? The ignitor chip plate is generally found on the opposite side of the driver's side shock tower. So its on the left on a JDM car, right on a USDM car.

Hey speed, can you post the diagram for how to route the vacum lines with that solenoid. Thnx

Yes

[Neil]

my ignitor isnt mounted anywhere, its held well enough in place by the rigidity of the harness it plugs into, right by the passenger side strut tower.

I got that mounting bracket with the solenoids too, i tossed it, since its supposed to fit on the US drivers side somewhere and the solenoids are essentially useless anyway. just run your w/g line right from the smic pipe to the w/g unless you have a boost controller, then route accordingly.

I tapped 12psi occasionally on my beat *** smic and i was fine. dude's supercharge 10psi without an intercooler all day on high compression motors and theyre fine, 10psi on the stock sidemount is swayze. The biggest problem with the sidemount is it doesnt flow for ****, CFM's suffer at higher boost levels

[IDriveFords]

Ok just to double check: running with that solenoid won't have any ill effects even with an aftermarket FMIC and BOV correct? In otherwords I won't have to worry about the boost creeping or spiking will I?

[Neil]

If you use it and it isnt working properly, You might spike or get boost creep. this also might happen if your wastegate diaphragm is bad, but that's unlikely..

honestly I highly suggest ditching that solenoid. The amount it might decrease the time it takes to spool to 7psi is hardly worth it.

I really really really really wanted to use it too to make my swap as complete a swap as possible cuz i was like "well Nissan thought it was a good idea", but trust me it isn't necessary. It might sound harsh to throw it away but I promise the first time you go drive the car with a line right to the wastegate, you won't even think you should install it. Besides, if you ever get a boost controller, which you will, (or you should, since you spent the money on a FMIC which isnt really even worth it for a T25) it bypasses it anyway. If you get one that hooks up to the solenoids harness, its just being redundant and adds another thing to troubleshoot if something isnt working right.

[PantherRacer]

Honostly the stock S13 SR actually runs at about 11 psi. 99% of people on this board think otherwise but 99% of the people on this board tossed the stock boost pressure solenoid during the swap. Tossing this unit limits the boost to 7 psi. Which is why everyone says stock is 7 psi. I have this unit on my car and it runs 11 psi when connected, 7 when its not connected, or the ecu is in limp mode. I have tested this on multiple cars with the exact same results.

So the smic can handle 10 psi fine because it was designed for over 10 psi stock.

Seriously....so I'm supposed to be running 11psi? DAMN. all this time I was stuck on 7 for no reason....time to....oh **** the solenoid is in the back trunk of the tercel! NOOOOOOOOOOOOOOOO ok, I REALLY need to get that back now...

and it works with some aftermarket ecu's to be a boost controller....hmmmmmmm

[SpeedRacer1]

The solenoid will make the car feel a lot better than the 7 psi. It is much more sporty.

If the solenoid is hooked up wrong the only thing that should happen is that your boost will drop to about 6.5 psi. If this happens recheck your vacuum lines and check the ECU for codes. If you are throwing an error code the ECU will limit boost to 6.5psi.

[efrain240sx]

Honostly the stock S13 SR actually runs at about 11 psi. 99% of people on this board think otherwise but 99% of the people on this board tossed the stock boost pressure solenoid during the swap. Tossing this unit limits the boost to 7 psi. Which is why everyone says stock is 7 psi. I have this unit on my car and it runs 11 psi when connected, 7 when its not connected, or the ecu is in limp mode. I have tested this on multiple cars with the exact same results.

So the smic can handle 10 psi fine because it was designed for over 10 psi stock.

If the ECU is in limp mode how should the car run? Also if you increase the boost to 11psi with a manual waste gate will that take the ECU out of limp mode?

[SpeedRacer1]

If the ECU is in limp mode how should the car run? Also if you increase the boost to 11psi with a manual waste gate will that take the ECU out of limp mode?

The ECU reacts differently to different errors. For instance the when the ECU throws a MAFS circuit code, the engine will not rev above approximately 2500 RPM's, while if the engine coolant temp sensor is disconnected the engine will run fine once started, but the boost will be limited to 6.5 psi.

stop saying s13sr's are 11psi stock. the ****ing wastegate has a 7lb spring. the little solenoid is not an actuator it's a SOLENOID which is on/off, when boost reaches 7psi it opens which snaps the wastegate open instead of letting it open gradually, which gives you a little more low end response.

Nearly the same effect can be had by inserting a restrictor in the line from the intercooler to the wastegate.

The stock SR runs 11 psi stock, you have no idea what you are talking about unless you have run the solenoid. Until that time your opinion means nothing. The engine runs like it has a closed wastegate, once it reaches 11 psi, the solenoid opens the wastegate to stabilize the boost. If the wastegate ran completly disconnected the turbo would run until it blew up. It has very little, if any, effect on low end response. It add power above approximately 3500 RPM's and high throttle.

[Neil]

my car must be in limp mode going on over a year now.

HM THATS WEIRD IT SEEMS TO RUN GREAT AT 14PSI

yeah i deleted my post because i didnt read what you said and I knew you were going to give me **** for it. i'll rephrase... I'm surprised that little on/off solenoid can regulate boost pressure at 11psi considering how beefy and noisy most ebc actuators on the market are.

im glad i have a boost controller then, since i tossed my solenoid out.

and i guess by low end response i didnt mean low rpm. i was thinking more along the lines of 'light footed' aka "the gate stays closed anywhere between 0 and 7psi" which WILL help make the car feel peppier, obviously if youre in the right rpm range to provide the exhaust flow. I know how a wastegate works and at what rpm a t25 can start adding power.
Modified by Neil at 6:06 AM 2/3/2007

[efrain240sx]

kool thanks for answering my question speedracer, but tell me if I were increase boost to 12psi with a manual wastegate would that get the ecu out of limp mode or do I need to use the boost solenoid to get it out limp mode? thanks

[SpeedRacer1]

If you used a manual boost controller you could set the boost to 12 psi and it would have no effect on the ECU. The stock solenoid is the only way the ECU knows what the boost pressure is at, if you dont have it the ECU just pretends it is at the stock setting. If your ECU is in limp mode, run the ECU for error codes and fix the errors, this is the only way to reset the ECU.

[efrain240sx]

It usually comes attached to the igniter chip plate. It is gold while the EGR piece is green plastic. You can toss the EGR part but the boost control solenoid is useful for more boost. Also later on some aftermarket ECU's, like the Power FC, can plug into directly into the stock boost control solenoid to control boost like a boost controller.

Boost control solenoid is on the left, if you need instructions on how to run the vac lines let me know.

Hey speedracer I have one more question for you. I found my boost solenoid and I tried hooking it up, but I don't think I have it on right because all I get is 9 psi from the turbo. These is how I have it hooked up (looking on the pic you posted) I have the bottom one T-off the throttle body the one in top is T-off on the hose going from the cold pipe to the waste gate is these write? also I tried using the diagram from the s14 FSM but its to hard to tell which goes to were

[SpeedRacer1]

Nothing off of the solenoid should be hooked to the throttle body. The bottom vac line runs like this: Boost solenoid > Tee'd between the wastegate and cold pipe nipple. The top line runs to the hole on your intake tube that may be capped.

[efrain240sx]

well once again sir, you are right. I am able to hit 10.5 psi now with my boost solenoid. You are the man speedracer

[SpeedRacer1]

Im glad it worked for you.

[Brice Peters]

Does the plug that is connecting to the solenoid need to be plugged in for it to work or would plugging it in cause it to limit it back to 7psi again?

[SpeedRacer1]

If the plug is disconnected it should run 7 psi.

[9240sx]

Would there be any advantage to hooking this solenoid up if i all ready have a profecB running 13psi???

[SpeedRacer1]

Would there be any advantage to hooking this solenoid up if i all ready have a profecB running 13psi???

No, not really.