Absolutely! However, these things don't(IMO) have the same precise control of the turbine side like say a Gt40vgt might. Granted you still have problems with sticking vanes in some areas, whatever but at the end of the day you can manipulate VGT tables far beyond a spool valve. The biggest problem I have with the setups is that they end up choking down one bank tremendously(as they are intended to, im aware but it flirts disasterously close with High exhayst bp, egt's, Etc.,)Big singles and spool valves on 6.0's still don't spool like you'd think with the valve in place. To me, it's worth the exta time to sit down and size your turbine side and exhaust housing properly to get what you are after. I see the advantages of the quick spool valve, sure, and it very well may be effective for some but unfortunately for most, it is just one of those deals that doesn't work out on the road like it does on paper.
Besides, why add more problems to an already struggling turbo charger? Things added in to the equation after the spool valve install like adding another exhaust gasket, the very high risk of the valve sticking closed, not opening at desired RPM's. All things that make me believe they are not worry the hassle.
Ask Matt Maroni what he thinks about Spool Valves, or Craig at MPD.
