get your cooling system pressure tested and checked for exhaust gases in the coolant.then go from there.also clean the isv to possibly stabilse tickover/revs.
i have the crankcase ventilation to atmosphere on my v2.on investigating rumbling bearing that were changed the oil seal behind the impeller,it had cracked.the sc has done 60k miles.new bearing has made the engine made positive boost as soon as you blip the throttle(boost gauge reading).
found on a vr sc et up,that v-power has no equal!throttle response,in gear acceleration-faster pick up/pulls stronger.the bp,tesco etc..etc.. is much of a muchness,but a lot better than the 95ron crap.the v power doen't last as long as the other superunleaded-but that's the pay off?
i use a kn filter strapped straight on the sc(v2).the filter has an internal diameter of 89mm.the v1 and v2 are slightly bigger units than the v9.just trunk some cold air feeds to it and away you go.part no rc-3180.i am running stage 2(8.5psi).feeds 295-317bhp-depending where you go for rr!
never been on the track with my sc vr,but the previous owner did-with no performance issues.running a v2 with similar mods.i would suggest heatsoak/or like you say inlet temps.does the z sc have a restricting air filter underneath the airbox area?i have fabricated 3 cold air feeds piped to the sc air filter.the air filter bolts straight on to the v2-and just fits due to limited room!its quite a large k& n unit designed for competion use.vince commented that getting more airto the sc is a plus.hope this helps!
i have the stealth BVH,if you're going down the the FI route buy the the 248s instead of the 268s as they are a better match to the vgi/sc combo as i have.you will only end up taking them out!with the sc and all the mods mentioned it would be a pussy cat to drive until you hit 2k revs anyway.
on the vr jack the back end up(petrol flap side).its in a casing.unbolt the casing.you will have an inlet/outlet secured pipes with jubilee clips.clamp these for fuel spillages(have a bowl ready!).take the clips off and fit the new filter-hey presto!
i get if you hike the power you have to protect it.if you want to push 350bhp you would have to take these measures.300hp should be enough for MOST people?lol.
engine coolant 50% strength.aquamist-1 part screen wash to 4 parts any supermarket bottled water.do you have an oil cooler,if not seems that you'd benefit.
that pic looks familiar pete-lol!yes they do work fine.switching point is 4k revs.i get a burst of extra power at 5k.dunno whether thats the 248s,sc on full boost from 4k onwards,or the aquamist which works from 4k onwards.i would say its the mani wide open while the sc is on full boost??
i went aswell.dark grey sc vr.spoke to big lee m,gaz.good day/weather.kids thought it was great to be asked questions about 'our' car-lol.are some of that polished metal in the building driven everyday?some put a lot of time and effort into thier rides-respect.but we are all in to our dubs for different reasons.