JohnnyW Posted April 2, 2008 Author Share Posted April 2, 2008 So acording that post you do actually know that the exhaust is the problem. As you said Andy put his on and it achived the higher boost as yours was too restrictive. Why did he remove the boost controller when it was working correctly? Think you might have to bite the bullet and get a less restrictive exhaust. Dr Doom: SMIC looks in decent enough condition, what's the best way to check for boost leaks? Quote Link to comment Share on other sites More sharing options...
letmeshowyou Posted April 2, 2008 Share Posted April 2, 2008 exhaust being restrictive or otherwise, a working boost controller WILL raise boost. You could quite easily run a car with both cats, and standard exhaust at higher boost with a working controller - whether this is a good idea or not is another matter. Quote Link to comment Share on other sites More sharing options...
QSC Posted April 2, 2008 Share Posted April 2, 2008 Andy took the boost controller off because he said it was unnecessary. My point is, how come it didn't work even with the restrictive exhaust ? Does a boost controller increase the level of boost on an otherwise totally stock car ? (Not a sensible thing to do I know) Quote Link to comment Share on other sites More sharing options...
QSC Posted April 2, 2008 Share Posted April 2, 2008 exhaust being restrictive or otherwise, a working boost controller WILL raise boost. You could quite easily run a car with both cats, and standard exhaust at higher boost with a working controller - whether this is a good idea or not is another matter. Just seen your post after making above post - don't understand why it didn't work then - Andy H said it was a waste of money... Quote Link to comment Share on other sites More sharing options...
Nic Posted April 2, 2008 Share Posted April 2, 2008 Andy took the boost controller off because he said it was unnecessary. My point is, how come it didn't work even with the restrictive exhaust ? Does a boost controller increase the level of boost on an otherwise totally stock car ? (Not a sensible thing to do I know) Yes even if the exhaust is restrictive a boost controller should be able to raise the boost. You say you have both cats removed, even if the exhaust is restrictive it won't be more restrictive than the stock exhaust with both cats in place. Quote Link to comment Share on other sites More sharing options...
Scott Posted April 2, 2008 Share Posted April 2, 2008 Just seen your post after making above post - don't understand why it didn't work then - Andy H said it was a waste of money... This is the point we have been trying to explain to you. A boost controller will definitely raise the boost. Its also been explained why. The most obvious reason is that the boost controller was faulty. Having the cats and a restrictive exhaust means that the pressure will build up more causing more heat which is not a good idea. I have both my cats in at the moment and i'm running around 1-1.1 bar. This is done via the MINES ecu. How that works i don't know as i'm guessing the ECU can't fool the actuator. I'm saving up at the moment for a couple of de-cat pipes so that the pressure is a little safer. Scott =op Quote Link to comment Share on other sites More sharing options...
tDR Posted April 2, 2008 Share Posted April 2, 2008 Yes even if the exhaust is restrictive a boost controller should be able to raise the boost. You say you have both cats removed, even if the exhaust is restrictive it won't be more restrictive than the stock exhaust with both cats in place. My thoughts exactly. Your custom twin exit is never going to be as restrictive as a stocker with cats in (have you seen the diameter and bends in a stocker?). I've seen many turbocharged cars running stock exhaust systems with cats in and increased boost using an EBC - it's not a problem and I've never had a problem setting up an EBC on any car. They're actually pretty simple if you have an idea of what's going on as you adjust it and are familiar with a menu driven computer interface. What diameter piping was used in your custom system and who built it - any pictures of the underside of the car with it fitted so we can spot for any obvious restrictions in it? Or alternatively pictures of the same company's work on other cars? I would conclude from all of this that either the boost controller was installed incorrectly (solenoid valve boost pipes in the wrong ports because of incorrectly installed attachment barbs most likely) or was not set up. By default they will not alter boost at all - you have to run through the menus and make adjustments. There is an outside chance the unit itself is faulty but after seeing many botched EBC installs I'd double check that. I would not conclude that an EBC is a waste of money with your exhaust system given what you are boosting with that setup - it should have been the perfect compliment and I would definately have one installed and set up correctly. An EBC is a waste of money IMO if your exhaust system is free flowing enough to allow you to exceed 1.2bar and have to fit a restrictor ring to keep it at that level or below. There are differing views on that however with people fitting 1bar rated restrictor rings to allow for seasonal boost changes according to colder weather etc. and using the EBC when necessary to up boost to 1.2 bar or thereabouts. Hopefully you're getting a clearer picture of what's going on with your car from this thread and that it helps the original poster? Cheers, Brian. Quote Link to comment Share on other sites More sharing options...
Scott Posted April 2, 2008 Share Posted April 2, 2008 Thought i might as well ask you here... Do you know how the mines ECU allows the boost limit to be raised to 1bar? I can't really get it in my head as i thought the actuator was mechanically operated. Cheers Scott =op Quote Link to comment Share on other sites More sharing options...
QSC Posted April 2, 2008 Share Posted April 2, 2008 Thanks a lot for all your input Brian and Nic, you've certainly enlightened me on a good few things there - I have pics of the exhaust somewhere, but can't find them at the moment, the pipe is two inches I believe, made by MIJ in Brum. I honestly do appreciate the advice - what I'm still confused about is why Andy H didn't set up the EBC (unless it's faulty, but he didn't say it was), but that's my problem - Andy & his dad don't share some of your viewpoints regarding EBCs obviously. Quote Link to comment Share on other sites More sharing options...
tDR Posted April 3, 2008 Share Posted April 3, 2008 No probs QSC Thought i might as well ask you here... Do you know how the mines ECU allows the boost limit to be raised to 1bar? I can't really get it in my head as i thought the actuator was mechanically operated. Cheers Scott =op My guess would be through the stock VSV (same as the EBC solenoids in function really) Toyota tend to use to limit boost to a lower level in the lower gears to protect transmissions. It's done in the reverse of how you may think - the stock VSV (vacumn switching valve BTW) is effectively used to raise boost by the stock ECU in gears above those where they want to protect the transmission - as per my last post the same method is used whereby boost is bled away from the actuator. An actuator is basically a diaphram in a brass cylinder looking thing with a rod coming out the back which attaches to the wastegate flap at the exhaust end of the turbo(s) - the diaphram moves backwards inside the cylinder when enough pressure is exerted upon it, thus causing the rod to move and open said flap it is attached to. Here's some pics of an internally wastegated turbo to help you understand what I'm waffling on about: ^^ See the cylinder and the rod coming out? That rod attaches to the internal wastegate flap shown here: http://www.frsport.com/images/detailed_images/Garrett_GT28R_5_2303.jpg When that flap opens is determined by the pressure rating of the actuator. It is fed pressure from whatever pressure source via the hose barb coming out of it with a hose attached (usually the compressor housing, the front part of the turbo) - this is how boost is regulated. When the flap opens the turbo is effectively maintained at whatever RPM / boost pressure it's at by means of exhaust gas exiting through that flap and out your exhaust system. Toyota's actuators tend to have 2x hose barbs on the actuator - one to the pressure source to regulate boost pressure and the other to the stock VSV. That way the ECU can bleed boost away from the actuator using the stock VSV. In the gears where Toyota want to protect the transmission, no boost is bled away and the actuator operates the wastegate flap at whatever psi of boost it's rated for - say 10psi. Now we get to the higher gears, the ECU uses the stock VSV to raise boost by say 3psi to 13psi by bleeding 3psi of boost away from the actuator. Your Mines ECU - as it has been reprogrammed - can use this functionality to make the car boost differently to how Toyota intended - full and higher boost in all gears etc. Hope this all didn't sound too confusing - lots of stuff to try to explain!! Cheers, Brian. Quote Link to comment Share on other sites More sharing options...
Jspec Germany Posted April 3, 2008 Share Posted April 3, 2008 No probs QSC My guess would be through the stock VSV (same as the EBC solenoids in function really) Toyota tend to use to limit boost to a lower level in the lower gears to protect transmissions. It's done in the reverse of how you may think - the stock VSV (vacumn switching valve BTW) is effectively used to raise boost by the stock ECU in gears above those where they want to protect the transmission - as per my last post the same method is used whereby boost is bled away from the actuator. An actuator is basically a diaphram in a brass cylinder looking thing with a rod coming out the back which attaches to the wastegate flap at the exhaust end of the turbo(s) - the diaphram moves backwards inside the cylinder when enough pressure is exerted upon it, thus causing the rod to move and open said flap it is attached to. Here's some pics of an internally wastegated turbo to help you understand what I'm waffling on about: http://www.made-in-china.com/image/4f0j00ceBQkZpJbaqtM/T3-T4-Rb20-Turbo-Turbocharger-V-Band-Internal-Wastegate.jpg http://www.streetunit.com/v/vspfiles/photos/GT28R-2T.jpg ^^ See the cylinder and the rod coming out? That rod attaches to the internal wastegate flap shown here: http://www.frsport.com/images/detailed_images/Garrett_GT28R_5_2303.jpg When that flap opens is determined by the pressure rating of the actuator. It is fed pressure from whatever pressure source via the hose barb coming out of it with a hose attached (usually the compressor housing, the front part of the turbo) - this is how boost is regulated. When the flap opens the turbo is effectively maintained at whatever RPM / boost pressure it's at by means of exhaust gas exiting through that flap and out your exhaust system. Toyota's actuators tend to have 2x hose barbs on the actuator - one to the pressure source to regulate boost pressure and the other to the stock VSV. That way the ECU can bleed boost away from the actuator using the stock VSV. In the gears where Toyota want to protect the transmission, no boost is bled away and the actuator operates the wastegate flap at whatever psi of boost it's rated for - say 10psi. Now we get to the higher gears, the ECU uses the stock VSV to raise boost by say 3psi to 13psi by bleeding 3psi of boost away from the actuator. Your Mines ECU - as it has been reprogrammed - can use this functionality to make the car boost differently to how Toyota intended - full and higher boost in all gears etc. Hope this all didn't sound too confusing - lots of stuff to try to explain!! Cheers, Brian. Wow! Great post even. I hope this makes sense now. Quote Link to comment Share on other sites More sharing options...
Scott Posted April 3, 2008 Share Posted April 3, 2008 No probs QSC My guess would be through the stock VSV (same as the EBC solenoids in function really) Toyota tend to use to limit boost to a lower level in the lower gears to protect transmissions. It's done in the reverse of how you may think - the stock VSV (vacumn switching valve BTW) is effectively used to raise boost by the stock ECU in gears above those where they want to protect the transmission - as per my last post the same method is used whereby boost is bled away from the actuator. An actuator is basically a diaphram in a brass cylinder looking thing with a rod coming out the back which attaches to the wastegate flap at the exhaust end of the turbo(s) - the diaphram moves backwards inside the cylinder when enough pressure is exerted upon it, thus causing the rod to move and open said flap it is attached to. Here's some pics of an internally wastegated turbo to help you understand what I'm waffling on about: http://www.made-in-china.com/image/4f0j00ceBQkZpJbaqtM/T3-T4-Rb20-Turbo-Turbocharger-V-Band-Internal-Wastegate.jpg http://www.streetunit.com/v/vspfiles/photos/GT28R-2T.jpg ^^ See the cylinder and the rod coming out? That rod attaches to the internal wastegate flap shown here: http://www.frsport.com/images/detailed_images/Garrett_GT28R_5_2303.jpg When that flap opens is determined by the pressure rating of the actuator. It is fed pressure from whatever pressure source via the hose barb coming out of it with a hose attached (usually the compressor housing, the front part of the turbo) - this is how boost is regulated. When the flap opens the turbo is effectively maintained at whatever RPM / boost pressure it's at by means of exhaust gas exiting through that flap and out your exhaust system. Toyota's actuators tend to have 2x hose barbs on the actuator - one to the pressure source to regulate boost pressure and the other to the stock VSV. That way the ECU can bleed boost away from the actuator using the stock VSV. In the gears where Toyota want to protect the transmission, no boost is bled away and the actuator operates the wastegate flap at whatever psi of boost it's rated for - say 10psi. Now we get to the higher gears, the ECU uses the stock VSV to raise boost by say 3psi to 13psi by bleeding 3psi of boost away from the actuator. Your Mines ECU - as it has been reprogrammed - can use this functionality to make the car boost differently to how Toyota intended - full and higher boost in all gears etc. Hope this all didn't sound too confusing - lots of stuff to try to explain!! Cheers, Brian. Explanation of the year Clear as crystal now. I also know that little bit more about the turbo operation. Its amazing what you can learn without picking up a spanner lol. Scott =op Quote Link to comment Share on other sites More sharing options...
JohnnyW Posted April 3, 2008 Author Share Posted April 3, 2008 Superb TRD! Do you not fancy a trip over to Dunfermline to sort my car Quote Link to comment Share on other sites More sharing options...
tDR Posted April 3, 2008 Share Posted April 3, 2008 Superb TRD! Do you not fancy a trip over to Dunfermline to sort my car lol thanks - what have you done to it? Cheers, Brian. Quote Link to comment Share on other sites More sharing options...
JohnnyW Posted April 3, 2008 Author Share Posted April 3, 2008 lol thanks - what have you done to it? . What have I not done to it The car is running brilliantly really happy with it just wanting to get a bit more power out of it but not quite getting there (hence this thread) looks like an EBC is the way forward. Quote Link to comment Share on other sites More sharing options...
Dazzi Posted April 4, 2008 Share Posted April 4, 2008 Just to confuse this 'only able to turn up boost, not lower it' stuff. This is taken from AEM Boost controller blurb: If you want more boost press the button on the right of the gauge face, and if you want less boost press the button on the left of the gauge face. Quote Link to comment Share on other sites More sharing options...
Thorin Posted April 4, 2008 Share Posted April 4, 2008 Just to confuse this 'only able to turn up boost, not lower it' stuff. This is taken from AEM Boost controller blurb: If you want more boost press the button on the right of the gauge face, and if you want less boost press the button on the left of the gauge face. You still can't lower it to less than it would produce naturally without a boost controller. Quote Link to comment Share on other sites More sharing options...
Scott Posted April 4, 2008 Share Posted April 4, 2008 You still can't lower it to less than it would produce naturally without a boost controller. As above, Its a rookie mistake Quote Link to comment Share on other sites More sharing options...
Dazzi Posted April 4, 2008 Share Posted April 4, 2008 lol so basically you can only lower what you've increased but you can't lower what the turbos are churning out as standard. Quote Link to comment Share on other sites More sharing options...
Thorin Posted April 4, 2008 Share Posted April 4, 2008 lol so basically you can only lower what you've increased but you can't lower what the turbos are churning out as standard. That's correct yes Quote Link to comment Share on other sites More sharing options...
QSC Posted April 14, 2008 Share Posted April 14, 2008 Johnny - just to update you as we have similar problems, I fitted a manual boost controller, this one : http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&rd=1&item=120239901773&ssPageName=STRK:MEWN:IT&ih=002 & this sorted out the boost no bother, now too much boost in fact... Quote Link to comment Share on other sites More sharing options...
miko_supra Posted June 15, 2008 Share Posted June 15, 2008 did this ever get resolved? Quote Link to comment Share on other sites More sharing options...
jimmy_supra Posted June 28, 2008 Share Posted June 28, 2008 (edited) Hi I have just fitted both de cat pipes and a cat back hks super dragger exhaust to my jap spec tt and a 1.2 bar restrictor ring. When I first took it out it hit 1.0 bar of boost with a big kick. After this initial boost it is only boosting to 0.6 bar any ideas on what the problem could be any help would be greatly received thanks. Is there some sort of boost cut? I have fited a hks fcd and a walbro fuel pump and urated spark plugs. Edited June 28, 2008 by jimmy_supra (see edit history) Quote Link to comment Share on other sites More sharing options...
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