mrmyagiii Posted May 5, 2011 Share Posted May 5, 2011 How bad would it be if i get my 1st cat removed (and get full decat) and try and see how high my boost will take me without restrictor ring? If i push it once over 1.2bar it will not insta-screw up my engine i guess? Quote Link to comment Share on other sites More sharing options...
Robzki Posted May 5, 2011 Share Posted May 5, 2011 You have a fcd? Quote Link to comment Share on other sites More sharing options...
heckler Posted May 5, 2011 Share Posted May 5, 2011 How bad would it be if i get my 1st cat removed (and get full decat) and try and see how high my boost will take me without restrictor ring? If i push it once over 1.2bar it will not insta-screw up my engine i guess? pretty sure engine would be "OK" maybe - however I expect the turbos to go bang, spit the guts out the exhaust etc... just not worth it! Quote Link to comment Share on other sites More sharing options...
mrmyagiii Posted May 6, 2011 Author Share Posted May 6, 2011 Yes i have fcd. Really would it wreck my turbo's?i just wanna see if it would make than 1.2 couse i have an odd boost pressure problem.with boost controller "off" it makes~1bar and with boost controller on increased settings same pressure is reached.. Quote Link to comment Share on other sites More sharing options...
heckler Posted May 6, 2011 Share Posted May 6, 2011 Yes i have fcd. Really would it wreck my turbo's?i just wanna see if it would make than 1.2 couse i have an odd boost pressure problem.with boost controller "off" it makes~1bar and with boost controller on increased settings same pressure is reached.. prollonged use, or if you hit really high boost levels. I did this a long time ago, saw 1.7bar (by accident) few month later they died... Quote Link to comment Share on other sites More sharing options...
Nic Posted May 6, 2011 Share Posted May 6, 2011 Why do you want to? You *may* be okay briefly going above 1.2bar but a sustained pull could do damage. You risk a turbo blowing - there's a chance the turbine could be ingested by the engine - fueling running lean and excessively high exhaust temps. Quote Link to comment Share on other sites More sharing options...
Scott Posted May 6, 2011 Share Posted May 6, 2011 Going above 1.2bar shouldn't be a gamble as long as the revs are low. In order to hit 1.2bar at 6.5krpm the turbo is working it's little socks off. To produce 1.6bar at 4krpm would take less effort. It is a bit of a gamble though, up to yourself if you want to risk it. I can guarantee you will soar over 1.2bar though. Quote Link to comment Share on other sites More sharing options...
mrmyagiii Posted May 6, 2011 Author Share Posted May 6, 2011 i want to test it only once, becouse i`m thinking that the actuators are acting strange. It seems like they are opening all the way at 1.1 bar. When i`m switching my boost controller off it still hits 1.1bar wich should be stock level? I`m total clueless how i should rewire the actuators to stock config without the boost controller. Quote Link to comment Share on other sites More sharing options...
Nic Posted May 6, 2011 Share Posted May 6, 2011 i want to test it only once, becouse i`m thinking that the actuators are acting strange. It seems like they are opening all the way at 1.1 bar. When i`m switching my boost controller off it still hits 1.1bar wich should be stock level? I`m total clueless how i should rewire the actuators to stock config without the boost controller. What is the spec of the car? Do you have both cats fitted at the moment? Quote Link to comment Share on other sites More sharing options...
mrmyagiii Posted May 6, 2011 Author Share Posted May 6, 2011 only first cat.From there its open system. Exhaust temp not going abnormally high. Quote Link to comment Share on other sites More sharing options...
Scott Posted May 6, 2011 Share Posted May 6, 2011 Do you have a mines ECU? Quote Link to comment Share on other sites More sharing options...
Nic Posted May 6, 2011 Share Posted May 6, 2011 only first cat.From there its open system. Exhaust temp not going abnormally high. The boost pressure will rise above stock with one of the cats removed and a less restrictive exhaust fitted, 1.1bar sounds about right. Quote Link to comment Share on other sites More sharing options...
mrmyagiii Posted May 7, 2011 Author Share Posted May 7, 2011 Stock ECU.ok so with boostcontroller on "off" it should make around 1.1bar?i always thought i'd need boostcontroller to raise the pressure.but then why doesn't the boost raise when i raise it on controller?cause of first cat being too restrictive? Quote Link to comment Share on other sites More sharing options...
Scott Posted May 7, 2011 Share Posted May 7, 2011 The first cat is very restrictive. I'm surprised you are seeing 1.1bar to be honest. I have a mines ECU and with the 1st cat in I was seeing 1.1, all down to the ECU though. Quote Link to comment Share on other sites More sharing options...
Guest George89 Posted May 7, 2011 Share Posted May 7, 2011 How bad would it be if i get my 1st cat removed (and get full decat) and try and see how high my boost will take me without restrictor ring? If i push it once over 1.2bar it will not insta-screw up my engine i guess? I have pushed mine to 1.5 bar by accident today when i was testing boost controller. I only done it for 1 second but car completely lose traction at 60mph but i don' have LSD. I don't Recommend it at all! Quote Link to comment Share on other sites More sharing options...
Nic Posted May 7, 2011 Share Posted May 7, 2011 Stock ECU.ok so with boostcontroller on "off" it should make around 1.1bar?i always thought i'd need boostcontroller to raise the pressure.but then why doesn't the boost raise when i raise it on controller?cause of first cat being too restrictive? It's completely normal on a J-spec Supra for the boost pressure to raise when one or both cats are removed. On a stock Supra the cats restrict the exhaust flow which helps to regulate the peak boost pressure, remove a cat and the exhaust flow is improved and the small wastegate starts to struggle to regulate the boost. 1.0-1.1bar is normal with just the 1st cat fitted. Remove both cats and the boost pressure will spike to 1.5-1.6bar, which is the why a restrictor ring is fitted in the exhaust to reduce the boost to a safe limit. Have a read of this -> BPU. Quote Link to comment Share on other sites More sharing options...
CanisLupus Posted May 7, 2011 Share Posted May 7, 2011 My Jspec has almost Stock boost with a Nur Spec R and first Cat in. Quote Link to comment Share on other sites More sharing options...
Scott Posted May 7, 2011 Share Posted May 7, 2011 It's completely normal on a J-spec Supra for the boost pressure to raise when one or both cats are removed. On a stock Supra the cats restrict the exhaust flow which helps to regulate the peak boost pressure, remove a cat and the exhaust flow is improved and the small wastegate starts to struggle to regulate the boost. 1.0-1.1bar is normal with just the 1st cat fitted. Remove both cats and the boost pressure will spike to 1.5-1.6bar, which is the why a restrictor ring is fitted in the exhaust to reduce the boost to a safe limit. Have a read of this -> BPU. All my experience tells me that's wrong Nic. If you take the first cat out you will easily hit 1.1/1.2bar+. Taking out the 2nd cat did next to nothing in the 2 cars I've tried it in. Maybe 0.1bar but that was about it. The 1st cat is silly restrictive. Quote Link to comment Share on other sites More sharing options...
mrmyagiii Posted May 8, 2011 Author Share Posted May 8, 2011 Hm but don`t the wastegates just open all the way without a boost controller? Or can`t they still handle all the pressure with all cats removed? Then what is the purpose for a boost controller at my J-spec? Quote Link to comment Share on other sites More sharing options...
heckler Posted May 8, 2011 Share Posted May 8, 2011 Hm but don`t the wastegates just open all the way without a boost controller? Or can`t they still handle all the pressure with all cats removed? Then what is the purpose for a boost controller at my J-spec? That's the problem, the wastegate on a jspec is too small and cannot control the the boost above 1.2/1.3 bar. The idea is use a restrictor ring to bring the peak boost down to say. 1 bar then use a boost controller to increase it as the solenoid can now control the wastegate better then the ecu can. Quote Link to comment Share on other sites More sharing options...
mrmyagiii Posted May 8, 2011 Author Share Posted May 8, 2011 Ah i get it, so u restrict it with the ring to ~1 bar then raise it to be 1.2 with the controller being more precise as the RR. Quote Link to comment Share on other sites More sharing options...
heckler Posted May 8, 2011 Share Posted May 8, 2011 Ah i get it, so u restrict it with the ring to ~1 bar then raise it to be 1.2 with the controller being more precise as the RR. Bingo! Yup that the safe way to do it 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.