Originally Posted by
Chriscar 
What about the often heard theory that you shouldn't run your boost controller more than 2x the native wastegate pressure? Does the dual port config play into this?Short answer, yes the dual ports make the 2x limit a non-issue.
Long answer, internal wastegate actuators tend to be able to run close to 3x spring pressure I think before running into limits. (Mechanical advantage of the lever helps, as does the surface area ratio of the flapper cover versus diaphragm.) It's the external ones that have the 2x limit. That's with a ball-and-spring check valve boost controller only (basically). With tons and tons of other methods of control, you can get above those limits. Basically anything that lets you add pressure to
help the spring will let you go as high as you want. And this is what that second port is for as I'm sure you know.
I know most of this is old news to you, but some stuff in this thread might be new?
http://www.sr20-forum.com/information-library/16477-basics-boost-control-wastegates-how-turn-up-boost.html
Post #11 directly addresses your question.
Originally Posted by
blairellis I think the idea behind Bens post is to be able to tune the individual cells on the map in the very low boost areas which can be hard to tune with a higher wastegate spring? Correct me if Im off base here Ben...Yah, basically. I would have run their special order 3 psi spring if I'd be confident that it would hold the wastegate shut enough. Forge wasn't confident on that, so I went with their typical lowest spring of 5 psi. I can tune 5 psi across the rev range, then up the boost to 6 psi and tune, then to 7 psi and tune, and beyond. That way I can get the maps tuned in all areas without having to guess.
That's in theory anyway. Again, I have creep so that sort of throws a monkey wrench in all of that.
Also again with a proper boost controller I can do boost by rpm, boost by speed, boost by gear... Whatever. And traditionally the lowest boost pressure you can run is dictated by the wastegate spring. You can go higher easily, but not lower. So 5 psi in 1st gear should be nice if I can keep it that low.
AND I do want to keep torque low. I have a B13 transmission to baby, and a pretty mild clutch setup to baby, and limited traction, etc.
Nice! I like those! If one was so inclined, could you easily do a clear lens swap and throw some HIDs in there?
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