| The Re-circulating Valve... a better idea: How about instead of poking a hole in the turbo to intake manifold tube and just letting the air leak out wherever it wants to, we could direct that pressurized air somewhere else where we could hold on to it until we need it again? The intake side of the compressor housing (between the intercooler and the turbo) would be a good place wouldn't it? that way we wouldn't slow the turbine down and we would have that pressurized air that would have otherwise been thrown out, ready in a really good place when we need it. On top of that eve got still got the correct air/fuel ratio going since we're not throwing and air out, just moving it from one place to another within the intake system. Instead of having to suck in air for the turbo to pressurize, we've got some pressurized air with the correct fuel amount already waiting. Now we've got all the benefits of a blow off valve and then some. That's a re-circulating valve. Let's all order re-circulating valves then and skip the blow off valves completely. They're probably gonna cost a bit more than the blow off valves since they work a little better right? Now the big surprise... Re-circulating valves were engineered into the design of your 90+ twin turbo z on the drawing board... you've already got them... In conclusion: You could always disconnect your stock re-circulating valves (which you have to do to install blow off valves) and spend 500-600 bucks for blow off valves and what will you get? better performance? No, basically you do get the cool sneeze sound though you aren't going to be any faster than you were before (but you might sound like you are). If by chance you are running boost levels that exceed the airflow capacity of the re-circulating valves (~600+ hp?) then you've probably spent enough money and have enough experience and knowledge to know where the benefit reverses. For the rest of you who weren't in the know, I hope I've helped you save some time and money...
Nissan Z-cars - the best cars ever built...
Go Turbo, or go home
Bigger Downpipes = Bigger Man (and faster Z!) Scott Performance in Santa Clara - You guys are the best! |
