I was going to put mine on today but it would be incredibly hard with the 6468 on there because of the size of the turbo and the small fitting that has to go to the wastegate, so I will have to put a connection on there to make it work.
That's why I redesigned mine to use 1/4" fittings so the things can seal without leaking and blowing a headgasket. Not to mention, get rid of that stupid 90*.
I was pretty surprised to see they never caught on. Most people think that ancient design is solely an RJC thing I guess. (back in the old days it was called a 'Grainger valve' since all the parts could be found at Grainger Supply Company).
According to my power logger my boost kicks in at 2800rpm but doesn't get up to full boost till about 4800 rpm. I guess that isn't too bad with a 68 exhaust wheel and .85 A/R. Wondering what the RJC will be like on it?
Odds are it'll help with the spool time and get you a full boost sooner than the time it takes to reach 4800. Basically the valve keeps the wastegate shut until the last second then flings it open all at once when the desired boost level is reached. Say you're running 20PSI 'tuner style'... At around 10PSI your wastegate is almost halfway open. So only half the exhaust energy is accelerating the turbo. The other half is prematurely dumped. Since the turbo runs on exhaust energy, it doesn't make sense to dump energy while you're needing to add energy.
That being said, there's also a chance you can install the MBC and blow the tires off from faster spool. That's much more fun but will probably slow the car down.