For those of you running the Alta kit, where do you run the vacuum line for the BOV? I'm setting up a similar custom Greddy twincharge on a Scion xB and am trying to figure out where to run it. The BOV is a Turbo XS type H-RFL. The induction path goes:

Air filter --> intake --> turbo compressor --> pressurized piping w/ BOV attached --> air to air intercooler --> throttle body --> supercharger --> intake manifold --> combustion chamber.

I'm guessing it goes after the s/c on the intake manifold. If so, can I t-tap into the supercharger bypass valve vacuum line or should I tap a new hole in the intake manifold?

Here's the fit-check (minus intercooler)

 

BOV vacuum usually comes off the manifold, or where your Boost gauge is hooked up. Same kinda thing.

 

Thanks, when I was running just the supercharger boost gauge was t-tapped off the bypass valve vacuum control line (black hose in the front of the picture). Just wasn't sure with a twincharge configuration if it would be before or after the supercharger.

Here's the side view showing the manifold. You can see why fitting an intercooler post s/c would be a challenge.

 

Nice looking setup. How much power was it making with just the supercharger? What are you shooting for with the twincharge?

 

Don't laugh . Stock the dyno was 82 WHP. The supercharger bumped it up to 114 WHP on 7 psi and maxed out the stock injectors. I'm hoping for at least 150 WHP on 370 cc injectors, though I may need to insert a manual boost controller to increase the turbo output, the wastegate is set to 5 psi. I'll see what happens first with just the turbo intercooler and methanol.

The internals will be replaced to handle the extra boost, Toyota never really intended on this engine to make much power, it's the same one that's in the Echo.

 

It should be fun with almost double the stock hp. If it's not enough though you can always drop in a V8...

 

Yeah, that's actually the guy I bought the spare engine from. He didn't need it anymore, came with the auto trans as well.

 

well the BPV works the same way, so you can tap it off there too if you a re keeping that. It's basically the same idea, just venting to atmosphere instead of back into the the system.

 

Wait 82 whp with a stock s engine? Confused?

 

It's a Scion xB not a MCS.