Suprasteve Posted May 18, 2006 Share Posted May 18, 2006 all i done was replace the original hoses with silicon hoses but now when 2nd turbo kicks in it massively over boosts up to 1.8 bar in 4th (only done this once for a split second before shitting myself and took foot off the pedal) !!! . i've disconnected the boost controller so thats not the problem i fitted the new silicon hoses one at a time so i haven't accidently connected them up incorrectly. the only thing i can think of is i have no restrictor ring in (never have had) but this was never a problem before cos i only ever hit around 1 bar and needed the boost controller to up to 1.2 bar. Is it possible that i my have had a leak before with the old hoses and therefore didn't need the ring but now with the new hoses this is causing it to boost how it should and therefore require the ring? help please. Quote Link to comment Share on other sites More sharing options...
letmeshowyou Posted May 18, 2006 Share Posted May 18, 2006 sounds to me more like you've got a leak now... wastegate actuator hose maybe? Quote Link to comment Share on other sites More sharing options...
terribleturner Posted May 18, 2006 Share Posted May 18, 2006 If there was a boost leak you'd get less power, so if you ran at 1.2 you'd get 0.8bar Could possibly be the restrictor ring, but i wonder if it really couldd raise it to 1.8 with that missing. What size exhaust and decats do you have Steve?? Quote Link to comment Share on other sites More sharing options...
Matt H Posted May 18, 2006 Share Posted May 18, 2006 Must be bloody fast at 1.8 bar! Quote Link to comment Share on other sites More sharing options...
imi Posted May 19, 2006 Share Posted May 19, 2006 jspec @ 1.8bar aint a good idea.. mine spiked to 1.5 1.7 bar with a restrictor ring, i changed the hoses and now its back down to 1.2 where it should be Quote Link to comment Share on other sites More sharing options...
Suprasteve Posted May 19, 2006 Author Share Posted May 19, 2006 If there was a boost leak you'd get less power, so if you ran at 1.2 you'd get 0.8bar Could possibly be the restrictor ring, but i wonder if it really couldd raise it to 1.8 with that missing. What size exhaust and decats do you have Steve?? My thoughts exactly... Blitz Nur Spec Blitz Decat front Whifbitz Decat back Must be bloody fast at 1.8 bar! didn't feel any different TBH but then again i spotted the spike immediately and took foot of pedal. jspec @ 1.8bar aint a good idea.. mine spiked to 1.5 1.7 bar with a restrictor ring, i changed the hoses and now its back down to 1.2 where it should be not a good idea at all, thats why i'm very worried. It first happened when I noticed the boost controller beeping mad and it had recorded the max boost at 1.76 bar in 4th gear. But spikes about 1.45 bar in second. I haven't dare tried 4th gear again since. I'll disconnect and reconnect all the new hoses again checking for splits etc and buy new clamps (some of the old clamps are not very tight). If this doesn't fix it i have the restrictor ring from Whifbitz, i'll stick that on and see if that does the trick. When Whifbits fitted the decats and exhaust he was confused as to why my car didn't over boost then so this is why i mentioned putting the ring on. If anyone has any further ideas please let me know. Quote Link to comment Share on other sites More sharing options...
letmeshowyou Posted May 19, 2006 Share Posted May 19, 2006 James, I didnt mean a boost leak - if, for example there is a leak in the wastegate actuator hose it will never see the pressure it needs to open... Quote Link to comment Share on other sites More sharing options...
Soop Dogg Posted May 19, 2006 Share Posted May 19, 2006 Check the hoses on the wastegate actuator VSV too. If the VSV output hose to the wastegate has popped off, the wastegate aint going to open. Had exactly this problem on Angies car recently. 2 mins put it right. Quote Link to comment Share on other sites More sharing options...
letmeshowyou Posted May 19, 2006 Share Posted May 19, 2006 thats the one Steve give it a try! Quote Link to comment Share on other sites More sharing options...
Suprasteve Posted May 19, 2006 Author Share Posted May 19, 2006 Check the hoses on the wastegate actuator VSV too. If the VSV output hose to the wastegate has popped off, the wastegate aint going to open. Had exactly this problem on Angies car recently. 2 mins put it right. without trying to sound too stupid, i know i should know this but...going by Mawbys pics in the technical threads, i'm confused with which one i'm supposed to be looking for ??? a) "wastegate actuator" http://www.mkivsupra.net/vbb/attachment.php?attachmentid=13938&d=1112558977 b) "EGBV VSV" http://www.mkivsupra.net/vbb/attachment.php?attachmentid=13940&d=1112558977 c) "IACV VSV" http://www.mkivsupra.net/vbb/attachment.php?attachmentid=13940&d=1112558977 Can anyone please explain to me like i'm a 6 year old... Thanks Quote Link to comment Share on other sites More sharing options...
letmeshowyou Posted May 19, 2006 Share Posted May 19, 2006 the pipe you had your MBC on originally if that helps? Quote Link to comment Share on other sites More sharing options...
Suprasteve Posted May 19, 2006 Author Share Posted May 19, 2006 the pipe you had your MBC on originally if that helps? I now have an electronic boost controller and had to blank them off, maybe they aren't blocking properly ? Please see attached picture, are you referring to whats labelled 1 & 2 Quote Link to comment Share on other sites More sharing options...
letmeshowyou Posted May 19, 2006 Share Posted May 19, 2006 hang on just gonna go check on mine... Quote Link to comment Share on other sites More sharing options...
letmeshowyou Posted May 19, 2006 Share Posted May 19, 2006 number 3.... joins up to number 2 i think it is? Quote Link to comment Share on other sites More sharing options...
Suprasteve Posted May 19, 2006 Author Share Posted May 19, 2006 number 3.... joins up to number 2 i think it is? number 3 goes to my electronic boost controller. I didn't touch this hose when changing the others so it'll be a big coincidence if it is this that split / come off. I'll give it a good going over this weekend. I suppose the good news is it MUST be a suspect hose somewhere right ? as apose to major expensive problem. cheers for the replies. Quote Link to comment Share on other sites More sharing options...
Suprasteve Posted May 19, 2006 Author Share Posted May 19, 2006 ah ha... the cap had popped off of no.3 in my picture. I've put another cap on now and i'll test it in a min. Quote Link to comment Share on other sites More sharing options...
Suprasteve Posted May 19, 2006 Author Share Posted May 19, 2006 it all back to normal. thanks everyone. Quote Link to comment Share on other sites More sharing options...
letmeshowyou Posted May 20, 2006 Share Posted May 20, 2006 good to see this is sorted Quote Link to comment Share on other sites More sharing options...
JohnA Posted May 20, 2006 Share Posted May 20, 2006 Must be bloody fast at 1.8 bar! why? Quote Link to comment Share on other sites More sharing options...
Suprasteve Posted May 20, 2006 Author Share Posted May 20, 2006 I assume he was thinking more boost = more power, therefore 1.8 bar = huge power. on that note.. Quick question for you John, assuming it was 'safe' to increase boost to any pressure, with a BPU supra with stock injectors at what max boost what would you get optimum peak performance ? is it around the 1.2 bar or is that what is suggested because of fuelling and ceramic fins etc ? Quote Link to comment Share on other sites More sharing options...
mikeyh Posted May 31, 2006 Share Posted May 31, 2006 i have exactly the same problem as this but im confused what pipes you have put where. in your picture what should be on number 2 and number one:) Quote Link to comment Share on other sites More sharing options...
Suprasteve Posted May 31, 2006 Author Share Posted May 31, 2006 sent you a PM Quote Link to comment Share on other sites More sharing options...
JohnA Posted June 3, 2006 Share Posted June 3, 2006 ...Quick question for you John, assuming it was 'safe' to increase boost to any pressure, with a BPU supra with stock injectors at what max boost what would you get optimum peak performance ? is it around the 1.2 bar or is that what is suggested because of fuelling and ceramic fins etc ? Better late than never:d Assuming that the fuel pump is in good condition and the JSpec injectors are clean and flow well, then the fuelling should be adequate to deliver more juice than the turbos can deliver oxygen molecules (reliably + consistently). So the limiting factor would be turbocharger reliability. It goes downhill steeply after 1 bar and at 1.2bar it is pot-luck how soon you'll be posting here "is it time to go single?" There are unconventional ways of extending the 'dynamic' range of the turbos (like I do) but not tested on ceramic turbos (too much torque on the shaft and the turbine pops off!) Quote Link to comment Share on other sites More sharing options...
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