AlexJames Posted October 11, 2007 Share Posted October 11, 2007 ok guys, this has been driving me crazy for a while. The frist turbo comes online at just under 3k revs and stops about 4.5, the 2nd turbo comes online somewhere about 5.5 and charges up to the redline... there is a HUGE difference in the middle. Through reading on the forum I have read that thats a good indication that the BPU has been upgraded... A) Could someone explain this to me... B) The 2nd turbo doesnt come online if I have the acc pedal flat to the floor.. I can hear it spinning but no boost.. :rolleyes:I have to accell with the pedal about 3/4's of the way down and then bury the pedal when I feel the boost... is that normal? Any help is appreciated ! Quote Link to comment Share on other sites More sharing options...
TRD3000GT Posted October 11, 2007 Share Posted October 11, 2007 your first turbno does not stop an 4.5 revs.. If it does you have a serious problem. The supra running on twins goes from 1 turbo to both not one to another.... or you can run it in true twin and both come on together but there is a bit of spool time Quote Link to comment Share on other sites More sharing options...
AlexJames Posted October 11, 2007 Author Share Posted October 11, 2007 ahh ok, my mistake so the 1st keeps running but still.. the main problem is if I put my foot flat I get no 2nd boost ... Quote Link to comment Share on other sites More sharing options...
Thorin Posted October 11, 2007 Share Posted October 11, 2007 Sounds like a possible VSV problem. Has this only started happening recently? Had any other work done on the car? Quote Link to comment Share on other sites More sharing options...
AlexJames Posted October 11, 2007 Author Share Posted October 11, 2007 well I only just brought the RZ 2 months ago... it has a cat back HKS exhaust on it.. conversion chip for the mph, ...induction kit, dump valve and thats the lot... Both cats are still in... me confused :S Quote Link to comment Share on other sites More sharing options...
colsoop Posted October 11, 2007 Share Posted October 11, 2007 Have a look here fella http://www.mkivsupra.net/vbb/showthread.php?t=35926 this may help you diagnose what the problem is. As other have said it may be a vsv issue or perhaps a split vac hose. Quote Link to comment Share on other sites More sharing options...
AlexJames Posted October 11, 2007 Author Share Posted October 11, 2007 ahh cheers dude! this sounds alot like mine.. Ill give it a propper good read! Quote Link to comment Share on other sites More sharing options...
jaymdee Posted October 11, 2007 Share Posted October 11, 2007 My first turbo comes on at about 1800 and reaches its max boost (0.7Bar) by 2500 (I think). Prespool happens about 3600 and at 3800 both are working at full speed (1Bar). (definately by 4000) Yours seem VERY late IMO Quote Link to comment Share on other sites More sharing options...
adam bell Posted October 11, 2007 Share Posted October 11, 2007 i have mine set up to come in at the same time its great fun and it also makes driving in the wet better as you dont have any turbo till about 4.5k revs so you can drive it easier Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.