1st time intercooling questions before i do it

[Bheinen74]

going to intercool my 92 ss 5mt with the 06 WRX TMIC intercooler sitting on my office floor now,
There is no rush here. The boost guage is going in in a couple days to determine accuracy of guage based on factory boost levels, Car has oem VF11 turbo, with STi axleback, K&N panel filter ffresh tuneup, with new WRX clutch with WRX flywheel. Runnning Amoco Ulitmate gas, with I think a stock fuel pump.
I have quite a few questions, lengthy. so here they are. thanks in advance, I have searched threads for hours on this.....

-Should /Can I use my stock 92 BOV/ recirc valve with the 06 intercooler, with some custom piping off the intercooler? Will the stock 92turbo BOV leak or decrease my performance? what about when i turn the boost up?

-Have a MBC that will go in. Its a ball and spring unit. How do i disconnect/bipass the factory boost solenoid, so I am only using my MBC at a level I will choose. I plan to set it at 11/12psi to start. Do I bipass the stock boost solenoid, or will that foobar the ECU readings? If i do bypass the solenoid, can someone explain the hookups or a sketch?

-what is the max safe boost level to go to with this setup? Is 15/16 okay before it leans.?

thanks much. mainly just want some answers to the first 2 questions above.

[free5ty1e]

I'd say don't run more than 13 psig before you upgrade your fuel pump, then you should be able to run 15 psig if you'd like, even on the stock turbo. Intercooled of course.

As for the stock boost control solenoid, well the ECU has to either see it or a load connected or it will throw a CEL. Vikash recommends a 470-ohm 2-watt resistor be put electrically in place of the solenoid, which worked fine for me when I bypassed it.

Just remember the pressure sensor (next to the solenoid) still has to see boost, if your MAF sees enough airflow to surmise that you are boosting and the reading from the pressure sensor doesn't jive, you'll immediately get fuel cut. Remember too you'll need some sort of FCD if you're planning on seeing 13+ psig for any more than 2-3 seconds at a time...

Not sure on how to mate the stock BPV (its a bypass valve not a blowoff valve) since as soon as I went even top-mount intercooled I threw on an aftermarket BOV, which seemed much simpler to install anyway. Also remember that if you don't get a recirculating BOV, you might start having idle problems depending on the unit and how its set up. The HKS SSQV is a pull-type valve and has none of these issues, just an annoying whistle that you'll probably want to remove. The GReddy Type S is the other one I have, and it can have these issues but they're supposed to be solvable by hooking it up a little differently. I don't know, never had a chance to try it, once I bought the HKS I haven't had any BOV-related issues.

One more thing, the stock BPV will not hold boost levels much higher than stock, it will start leaking (weak push-type valve). This will especially cause issues if you don't have it set up as recirculating, but even so it will cause turbulence and disrupt the airflow...

Hope this helps.

[Bheinen74]

Thank you. Tell me more about this resistor. 470 ohm 2 watt.......
-is there a way to install the MBC without using the resistor. It sounds like a hassle to even find a resistor like that. Can I just install the MBC like after the factory boost solenoid, or at the turbo.? I am looking for just the 12 or 13 psi range now, until the Walboro 255 upgrade.
Oh, just got the boost guage installed, and completely hooked up.

tomorrow the WRX clutch and WRX flywheel are going in. Then for the next week we are suppose to have rain and cold.

[free5ty1e]

I'm not sure but you might be able to get away with just rerouting the vaccuum hoses to bypass the solenoid completely, and leave it connected electrically.

[555BCTurbo]

I'm not sure but you might be able to get away with just rerouting the vaccuum hoses to bypass the solenoid completely, and leave it connected electrically.

That's what I did, and it works great

[Threshld1]

It sounds like a hassle to even find a resistor like that.

www.digikey.com is your best friend for something like that

[Legacy777]

You can use the AT dropping resistor. It works fine and is the EXACT same connector plug as the wastegate actuator solenoid.

I did this when I was just running the wastegate spring boost pressure on my td05

[free5ty1e]

That is very good to note This is assuming, of course, that he'll want rock-hard shifts all the time, or that there is a shift kit with a separate dropping resistor in place. But good to know they use the same connector, how convenient.

Oh, and +1 for DigiKey... I get the majority of my electronic components from them.

[Legacy777]

I'm sure you could pickup another dropping resistor for a good price