supercharged_devil 0 Posted November 12, 2003 when is the boost pressure suppost to increase, at present its around 3500-4000 rpm, can you get the butterfly on the inlet manifold (return side) to shut earlier to bring the boost in sooner??? (its a G60 with a jabbasport stage4, 68mm pulley and chip, and giro valve. arround 0.9 bar) :twisted: Quote Share this post Link to post Share on other sites
GazzaG60 0 Posted November 12, 2003 you can adjust the butterfly. all it means is you get power before full throttle. bbost isn't sooner its just you dont have to put you foot down as far. downside to adjusting is that yuo may get lots of air and not the fueling requirement. You could fit a dump valve to the TB boost return. this would sharpen response but may create a on/off type switch. if you adjust the butterfly be v v v v careful with the plastic connections as they can break so i hear. Quote Share this post Link to post Share on other sites
h100vw 0 Posted November 12, 2003 It also means you'll use more petrol, for any given throttle position. Gazza is right about the plastic clips they are well brittle. Gvain Quote Share this post Link to post Share on other sites
G60Jet 1 Posted November 13, 2003 and a dump valve will coat the engine bay in oil mist too. Quote Share this post Link to post Share on other sites
VR6 0 Posted November 13, 2003 Sorry Nigel but being a G60 novice, where does the oil come into the equation? Quote Share this post Link to post Share on other sites
G60Jet 1 Posted November 13, 2003 Sorry Nigel but being a G60 novice, where does the oil come into the equation? The crank shaft breather vents into the boost return pipe, so when it goes back thought the charger into the main boost pipes it coats them with a film of oil. putting a dump valve in the main boost pipe will vent that oil vapour into the bay. Quote Share this post Link to post Share on other sites
VR6 0 Posted November 13, 2003 Ok that makes sense :) Why is there not a filter on the crankcase breather then? Surely oil vapour in the combustion cycle should be avoided? Quote Share this post Link to post Share on other sites
G60Jet 1 Posted November 13, 2003 the G-lader is oil feed and some oil gets into the system through that (leaky seals). i think im correct in saying all cars have a breather system. the oil should be minimal unless the valves are duff. Quote Share this post Link to post Share on other sites
Dubcharged 0 Posted November 13, 2003 Dont need a dump valve. Just remove the return tube altogether and you'll have a natural dump valve - the bypass butterfly. Quote Share this post Link to post Share on other sites