From sl300gullwing at gmail.com Wed May 26 22:58:00 2010 From: sl300gullwing at gmail.com (Arif Khan) Date: Wed May 26 22:58:52 2010 Subject: [mkiv] Re: boost problem In-Reply-To: <201005231700.o4NH02Ro000853@mkiv.com> References: <201005231700.o4NH02Ro000853@mkiv.com> Message-ID: <99BFBDDD-2252-4C83-BD6F-FDD929E83833@gmail.com> No apologies required, I certainly don't mind it so long as it's relevant. I drove the car in 2,3rd gear @ WOT and noticed the boost hit 5psi in 2nd gear and 10 psi in 3rd gear but it did not break the tires loose. I didn't stay in the redline before shifting which might invalidate the test. I think you're right that I probably have some boost leak but not enough to behave like this. My next steps are the following: 1. Recheck the bcc setting 2. Confirm timing 3. Replace all remaining vacuum/pressure hoses 4. Check the pressure tank circuit and VSVs Although, if the wastegate is weak wouldn't that manifest in symptoms like mine? Arif sl300gullwing@gmail.com > ---------------------------------------------------------------------- > > Message: 1 > Date: Sat, 22 May 2010 17:47:32 -0700 (PDT) > From: Thomas Bradley > Subject: Re: [mkiv] boost problem (update) > To: "The MKIV.com National Mailing List" > Message-ID: <697575.32167.qm@web56607.mail.re3.yahoo.com> > Content-Type: text/plain; charset=iso-8859-1 > > Sorry in advance for the ramblings of this post, I'm just thinking out loud and passing on some personal experiences with the 3 TT Supras I've owned over the years, 2 of which started out 100% factory stock when I got them and both had issues very similar to yours by the time they were 10 or more years old... > > Lance knows a LOT more about these things than most people including me, but I've owned 2 bone stock TT auto's (drove the first one for over a year bone stock before selling it to buy my house, and fully BPU'd and True-Twin'd the second one within a few weeks of buying it due to annoying random sequential system issues) and my TT 6-Speed came to me with upgraded down-pipe and cat-back but it was also otherwise stock, and it's been my experience that with a truly "stock" TT Supra (factory smic and full stock exhaust) 8-11psi is typical "stock boost" range in warm humid weather (0.6 - 0.8bar of boost) and in True-Twin mode the boost doesn't really hit until somewhere in the low to mid 4k rpm range, unlike sequential mode that is a much smoother boost curve that comes on much sooner. > True-Twin mode didn't really give me much more boost but what it did was make the boost far more consistent and the car much more predictable in my opinion versus sequential that was more like hit or miss at random when I floored it... > With a brand new sequential system I'm sure the twins would be consistent but as the system gets some age on it, it just seems that its' control of the #2 turbo becomes less and less predictable, leaving you with about half the normal "stock boost" and wondering why your twin-turbo car suddenly feels so slow. Between hardened vacuum lines, leaking vacuum lines, sticking VSV's, broken VSV's, etc, etc, the system starts to lose control and leave you without the #2 turbo more and more as time goes by. I also find that the VSV's are far more prone to failure on cars that aren't driven very often and/or aren't boosted to the point that the #2 kicks in very often (If at all), as opposed to those cars that get pushed hard regularly their whole lives and have actually worked the system's VSV's regularly their whole lives... It's fixable of course but in the meantime 'till you find and fix all the problems, the car is inconsistent and frustrating > to drive if you drive agressively and it's even more frustrating to troubleshoot as you're finding now... > > Although it introduces about 1k rpm more lag, that's exactly why I choose True-Twin mode personally, even on an automatic's, although on the auto with the "stock stall" torque converter it ends up being slower in the 1/4 mile than one with a properly functioning sequential system due to the extra turbo lag of True-Twin mode but I'm okay with that... > > Unless I misunderstood, you were originally getting about 5psi when you began your troubleshooting process and with real True-Twin you're now consistently getting twice that so it sounds to me like the turbos are now both working together as they should be although there still might be a mild boost leak and it seems to really point mostly to issues with the sequential system from how I interpreted all your info so far. > > What does the car do in True-Twin mode if you ride 1st or 2nd gear up to about 4,500 rpm's then cruise in that rpm range for like 10-30 seconds, then go WOT and stay in to to redline, then shift quick into the next gear and go WOT again? Do you get boost at WOT, is it the 10psi you get in higher gears above 4k rpm's, and does it hold well and pull strong the whole time and possibly even spin the rear tires? > > Granted I'm at BPU+ in true-twin mode but my 98TT 6-Speed does almost nothing 'till mid 4k's then turns into a fun little beast and working the gears to tach up high and have it still be up in the 4k range on shifts makes my car run strong through the 1/4mi and trap 118-125mph with consistent 12.0-12.2's and occasional high 11's with crappy 1.8-2.2 60ft's due to ongoing wheel-hop problems, and I'm not a drag racer at all, I prefer road courses myself. > > I also found that the 93TT auto in True-Twin mode was a slug below about 35mph but with the auto's gearing, once the tach hit mid 4k's the car always suddenly lunged and "hauled" for as long as you kept the accellerator down. From a stop True-Twin sucked on the auto but at any speed over 35mph it lunged hard and fast whenever I went WOT... > Then we BPU'd it and by mid 4k rpm's all of a sudden the car would break the tires free and get sideways without trac on and with it on the car would still spin' em and step out and you'd have to steer into it 'till the trac system kicked in and brought it back in line... > > Again, Lance is far better at diagnosing these sorts of things than I am and he is a huge asset to this list who is very greatly appreciated by everyone here that he has helped over the years including me, and this post is just my opinion so far on this topic and I hope it proves to be at least somewhat helpful for you. > > > Thomas > myothersupra > -------------- > 98TT 6-Speed MkIV > 93TT Auto MkIV (SOLD) > 92T Auto MkIII > 88 5-Speed MkIII > 84 5-Speed MkII P-Type > 81 5-Speed MkI > 01 E-Shift IS300 > 01 5-Speed ZRX-1200R > > --- On Sun, 5/16/10, Arif Khan wrote: > > > From: Arif Khan > Subject: [mkiv] boost problem (update) > To: mkiv@mkiv.com > Date: Sunday, May 16, 2010, 4:43 PM > > > After replacing the WG VSV, I wired up the actuators as outlined in the tech article on the mkiv site but unfortunately, there was no "ah ha" moment. Now, instead of building 7-8 psi, I'm getting a consistent 10 psi in 4th and 5th gear but no boost in 2 - 3 below 4k rpm. > > Before doing the above I did confirm that there was pressure in the line before the check valve on the IACV actuator as well as the lower EBV actuator. > > Furthermore, at the time I installed the replacement turbos I verified that all butterfly valve operations were smooth and unobstructed. > > As of now, I still have to test the pressure tank circuit and the wastegate actuator on #2 turbo. There is also an actuator on #1 but I can't get to it without removing the air tube assembly. > > Lance - > While I was searching the mkiv archive I came across a set of posts by you in which your coils had gotten weak and presented symptoms that appeared to be boost related. Could this be a similar case? > > > Thanks, > > Arif > sl300gullwing@gmail.com > > > > > > > _______________________________________________ > Mkiv mailing list > Mkiv@mkiv.com > http://www.mkiv.com/mailman/listinfo/mkiv > > > > > > ------------------------------ > > _______________________________________________ > Mkiv mailing list > Mkiv@mkiv.com > http://www.mkiv.com/mailman/listinfo/mkiv > > > End of Mkiv Digest, Vol 85, Issue 13 > ************************************ From jza80-alfvza at sbcglobal.net Wed May 26 23:36:30 2010 From: jza80-alfvza at sbcglobal.net (lance) Date: Wed May 26 23:36:46 2010 Subject: [mkiv] Re: boost problem In-Reply-To: <99BFBDDD-2252-4C83-BD6F-FDD929E83833@gmail.com> References: <201005231700.o4NH02Ro000853@mkiv.com> <99BFBDDD-2252-4C83-BD6F-FDD929E83833@gmail.com> Message-ID: <5785DD0B005442FCA902DEF093329944@Wolrab.local> Yes, if the wastegate spring is weak it will certainly be a root cause of low boost, but you wouldn't see 5 psi in second and 10 psi in third. You'd see either 5 or 10 regardless of gear. Have you tried disconnecting the wastegate entirely? Just cap the line and cap the wastegate to see if you can get at least 14 psi. I get 18 psi before the cat becomes the limiting factor. Your BCC setting won't make any difference because you're not hitting 14+ psi where boost cut occurs. I'd be pressurizing all the big pipes - basically capping off the tube going into the throttlebody, and putting another cap on the outlet of the twins, then pressurizing to find the leak. You've got to have a big leak somewhere - like a split hose you just can't see. The pressure tank only holds the actuators open when you shift. Its sole purpose is to provide constant pressure to the actuators through the VSVs so you don't have constant switching between modes when you shift gears. If it doesn't leak pressure, it can't cause low boost. Are you running a stock BOV? Have you checked it? Tony's car had a stock BOV with the typical blow through ventilation no matter what. Those things are junk after the disc inside hardens and shatters. It doesn't take long. I did a complete hose replacement on my car. It's a BIG PITA to get to the hoses on the back of the #2 turbo. I had my gearbox out and the engine tilted down while I was fixing the leak on the upper oil pan, so I was able to get to those hoses, but I really don't see any other way to do this without removing the engine. Seriously, those hoses are next to impossible to access with the engine and gearbox installed. Lance '93 TT 6 Speed Coupe -----Original Message----- From: mkiv-bounces@mkiv.com [mailto:mkiv-bounces@mkiv.com] On Behalf Of Arif Khan Sent: Wednesday, May 26, 2010 11:58 PM To: mkiv@mkiv.com Subject: [mkiv] Re: boost problem No apologies required, I certainly don't mind it so long as it's relevant. I drove the car in 2,3rd gear @ WOT and noticed the boost hit 5psi in 2nd gear and 10 psi in 3rd gear but it did not break the tires loose. I didn't stay in the redline before shifting which might invalidate the test. I think you're right that I probably have some boost leak but not enough to behave like this. My next steps are the following: 1. Recheck the bcc setting 2. Confirm timing 3. Replace all remaining vacuum/pressure hoses 4. Check the pressure tank circuit and VSVs Although, if the wastegate is weak wouldn't that manifest in symptoms like mine? Arif sl300gullwing@gmail.com > ---------------------------------------------------------------------- > > Message: 1 > Date: Sat, 22 May 2010 17:47:32 -0700 (PDT) > From: Thomas Bradley > Subject: Re: [mkiv] boost problem (update) > To: "The MKIV.com National Mailing List" > Message-ID: <697575.32167.qm@web56607.mail.re3.yahoo.com> > Content-Type: text/plain; charset=iso-8859-1 > > Sorry in advance for the ramblings of this post, I'm just thinking out loud and passing on some personal experiences with the 3 TT Supras I've owned over the years, 2 of which started out 100% factory stock when I got them and both had issues very similar to yours by the time they were 10 or more years old... > > Lance knows a LOT more about these things than most people including me, but I've owned 2 bone stock TT auto's (drove the first one for over a year bone stock before selling it to buy my house, and fully BPU'd and True-Twin'd the second one within a few weeks of buying it due to annoying random sequential system issues) and my TT 6-Speed came to me with upgraded down-pipe and cat-back but it was also otherwise stock, and it's been my experience that with a truly "stock" TT Supra (factory smic and full stock exhaust) 8-11psi is typical "stock boost" range in warm humid weather (0.6 - 0.8bar of boost) and in True-Twin mode the boost doesn't really hit until somewhere in the low to mid 4k rpm range, unlike sequential mode that is a much smoother boost curve that comes on much sooner. > True-Twin mode didn't really give me much more boost but what it did was make the boost far more consistent and the car much more predictable in my opinion versus sequential that was more like hit or miss at random when I floored it... > With a brand new sequential system I'm sure the twins would be consistent but as the system gets some age on it, it just seems that its' control of the #2 turbo becomes less and less predictable, leaving you with about half the normal "stock boost" and wondering why your twin-turbo car suddenly feels so slow. Between hardened vacuum lines, leaking vacuum lines, sticking VSV's, broken VSV's, etc, etc, the system starts to lose control and leave you without the #2 turbo more and more as time goes by. I also find that the VSV's are far more prone to failure on cars that aren't driven very often and/or aren't boosted to the point that the #2 kicks in very often (If at all), as opposed to those cars that get pushed hard regularly their whole lives and have actually worked the system's VSV's regularly their whole lives... It's fixable of course but in the meantime 'till you find and fix all the problems, the car is inconsistent and frustrating > to drive if you drive agressively and it's even more frustrating to troubleshoot as you're finding now... > > Although it introduces about 1k rpm more lag, that's exactly why I choose True-Twin mode personally, even on an automatic's, although on the auto with the "stock stall" torque converter it ends up being slower in the 1/4 mile than one with a properly functioning sequential system due to the extra turbo lag of True-Twin mode but I'm okay with that... > > Unless I misunderstood, you were originally getting about 5psi when you began your troubleshooting process and with real True-Twin you're now consistently getting twice that so it sounds to me like the turbos are now both working together as they should be although there still might be a mild boost leak and it seems to really point mostly to issues with the sequential system from how I interpreted all your info so far. > > What does the car do in True-Twin mode if you ride 1st or 2nd gear up to about 4,500 rpm's then cruise in that rpm range for like 10-30 seconds, then go WOT and stay in to to redline, then shift quick into the next gear and go WOT again? Do you get boost at WOT, is it the 10psi you get in higher gears above 4k rpm's, and does it hold well and pull strong the whole time and possibly even spin the rear tires? > > Granted I'm at BPU+ in true-twin mode but my 98TT 6-Speed does almost nothing 'till mid 4k's then turns into a fun little beast and working the gears to tach up high and have it still be up in the 4k range on shifts makes my car run strong through the 1/4mi and trap 118-125mph with consistent 12.0-12.2's and occasional high 11's with crappy 1.8-2.2 60ft's due to ongoing wheel-hop problems, and I'm not a drag racer at all, I prefer road courses myself. > > I also found that the 93TT auto in True-Twin mode was a slug below about 35mph but with the auto's gearing, once the tach hit mid 4k's the car always suddenly lunged and "hauled" for as long as you kept the accellerator down. >From a stop True-Twin sucked on the auto but at any speed over 35mph it lunged hard and fast whenever I went WOT... > Then we BPU'd it and by mid 4k rpm's all of a sudden the car would break the tires free and get sideways without trac on and with it on the car would still spin' em and step out and you'd have to steer into it 'till the trac system kicked in and brought it back in line... > > Again, Lance is far better at diagnosing these sorts of things than I am and he is a huge asset to this list who is very greatly appreciated by everyone here that he has helped over the years including me, and this post is just my opinion so far on this topic and I hope it proves to be at least somewhat helpful for you. > > > Thomas > myothersupra > -------------- > 98TT 6-Speed MkIV > 93TT Auto MkIV (SOLD) > 92T Auto MkIII > 88 5-Speed MkIII > 84 5-Speed MkII P-Type > 81 5-Speed MkI > 01 E-Shift IS300 > 01 5-Speed ZRX-1200R > > --- On Sun, 5/16/10, Arif Khan wrote: > > > From: Arif Khan > Subject: [mkiv] boost problem (update) > To: mkiv@mkiv.com > Date: Sunday, May 16, 2010, 4:43 PM > > > After replacing the WG VSV, I wired up the actuators as outlined in the tech article on the mkiv site but unfortunately, there was no "ah ha" moment. Now, instead of building 7-8 psi, I'm getting a consistent 10 psi in 4th and 5th gear but no boost in 2 - 3 below 4k rpm. > > Before doing the above I did confirm that there was pressure in the line before the check valve on the IACV actuator as well as the lower EBV actuator. > > Furthermore, at the time I installed the replacement turbos I verified that all butterfly valve operations were smooth and unobstructed. > > As of now, I still have to test the pressure tank circuit and the wastegate actuator on #2 turbo. There is also an actuator on #1 but I can't get to it without removing the air tube assembly. > > Lance - > While I was searching the mkiv archive I came across a set of posts by you in which your coils had gotten weak and presented symptoms that appeared to be boost related. Could this be a similar case? > > > Thanks, > > Arif > sl300gullwing@gmail.com > > > > > > > _______________________________________________ > Mkiv mailing list > Mkiv@mkiv.com > http://www.mkiv.com/mailman/listinfo/mkiv > > > > > > ------------------------------ > > _______________________________________________ > Mkiv mailing list > Mkiv@mkiv.com > http://www.mkiv.com/mailman/listinfo/mkiv > > > End of Mkiv Digest, Vol 85, Issue 13 > ************************************ _______________________________________________ Mkiv mailing list Mkiv@mkiv.com http://www.mkiv.com/mailman/listinfo/mkiv From sl300gullwing at gmail.com Thu May 27 22:14:04 2010 From: sl300gullwing at gmail.com (Arif Khan) Date: Thu May 27 22:14:46 2010 Subject: [mkiv] Re: Re: boost problem In-Reply-To: <201005271700.o4RH03Sm002463@mkiv.com> References: <201005271700.o4RH03Sm002463@mkiv.com> Message-ID: <7AC62ACB-EA65-443A-A990-17B1BCCEF1C1@gmail.com> I'll disconnect the wastegate and see what happens. I'm also leaning towards replacing all of the hoses regardless. Fortunately, I replaced the hoses in the back by #2 turbo when I did the turbo replacement. I am in fact running the stock BOV which I put back after removing the HKS SSQV (new) because it was venting to atmosphere. I seem to recall you mentioning that you had managed to install it in the stock location in recirc mode? If so, would you mind sharing some pictures? I'll put back the HKS in the meantime. Thanks for the continuing support. Arif sl300gullwing@gmail.com > ------------------------------ > > Message: 2 > Date: Thu, 27 May 2010 00:36:30 -0400 > From: "lance" > Subject: RE: [mkiv] Re: boost problem > To: "'The MKIV.com National Mailing List'" > Message-ID: <5785DD0B005442FCA902DEF093329944@Wolrab.local> > Content-Type: text/plain; charset="us-ascii" > > Yes, if the wastegate spring is weak it will certainly be a root cause of > low boost, but you wouldn't see 5 psi in second and 10 psi in third. You'd > see either 5 or 10 regardless of gear. Have you tried disconnecting the > wastegate entirely? Just cap the line and cap the wastegate to see if you > can get at least 14 psi. I get 18 psi before the cat becomes the limiting > factor. > > Your BCC setting won't make any difference because you're not hitting 14+ > psi where boost cut occurs. > > I'd be pressurizing all the big pipes - basically capping off the tube going > into the throttlebody, and putting another cap on the outlet of the twins, > then pressurizing to find the leak. You've got to have a big leak somewhere > - like a split hose you just can't see. > > The pressure tank only holds the actuators open when you shift. Its sole > purpose is to provide constant pressure to the actuators through the VSVs so > you don't have constant switching between modes when you shift gears. If it > doesn't leak pressure, it can't cause low boost. > > Are you running a stock BOV? Have you checked it? Tony's car had a stock > BOV with the typical blow through ventilation no matter what. Those things > are junk after the disc inside hardens and shatters. It doesn't take long. > > I did a complete hose replacement on my car. It's a BIG PITA to get to the > hoses on the back of the #2 turbo. I had my gearbox out and the engine > tilted down while I was fixing the leak on the upper oil pan, so I was able > to get to those hoses, but I really don't see any other way to do this > without removing the engine. Seriously, those hoses are next to impossible > to access with the engine and gearbox installed. > > Lance > '93 TT 6 Speed Coupe > > -----Original Message----- > From: mkiv-bounces@mkiv.com [mailto:mkiv-bounces@mkiv.com] On Behalf Of Arif > Khan > Sent: Wednesday, May 26, 2010 11:58 PM > To: mkiv@mkiv.com > Subject: [mkiv] Re: boost problem > > No apologies required, I certainly don't mind it so long as it's relevant. > > I drove the car in 2,3rd gear @ WOT and noticed the boost hit 5psi in 2nd > gear and 10 psi in 3rd gear but it did not break the tires loose. I didn't > stay in the redline before shifting which might invalidate the test. I > think you're right that I probably have some boost leak but not enough to > behave like this. My next steps are the following: > 1. Recheck the bcc setting > 2. Confirm timing > 3. Replace all remaining vacuum/pressure hoses > 4. Check the pressure tank circuit and VSVs > > Although, if the wastegate is weak wouldn't that manifest in symptoms like > mine? > > Arif > sl300gullwing@gmail.com > > > >> ---------------------------------------------------------------------- >> >> Message: 1 >> Date: Sat, 22 May 2010 17:47:32 -0700 (PDT) >> From: Thomas Bradley >> Subject: Re: [mkiv] boost problem (update) >> To: "The MKIV.com National Mailing List" >> Message-ID: <697575.32167.qm@web56607.mail.re3.yahoo.com> >> Content-Type: text/plain; charset=iso-8859-1 >> >> Sorry in advance for the ramblings of this post, I'm just thinking out > loud and passing on some personal experiences with the 3 TT Supras I've > owned over the years, 2 of which started out 100% factory stock when I got > them and both had issues very similar to yours by the time they were 10 or > more years old... >> >> Lance knows a LOT more about these things than most people including me, > but I've owned 2 bone stock TT auto's (drove the first one for over a year > bone stock before selling it to buy my house, and fully BPU'd and > True-Twin'd the second one within a few weeks of buying it due to annoying > random sequential system issues) and my TT 6-Speed came to me with upgraded > down-pipe and cat-back but it was also otherwise stock, and it's been my > experience that with a truly "stock" TT Supra (factory smic and full stock > exhaust) 8-11psi is typical "stock boost" range in warm humid weather (0.6 - > 0.8bar of boost) and in True-Twin mode the boost doesn't really hit until > somewhere in the low to mid 4k rpm range, unlike sequential mode that is a > much smoother boost curve that comes on much sooner. >> True-Twin mode didn't really give me much more boost but what it did was > make the boost far more consistent and the car much more predictable in my > opinion versus sequential that was more like hit or miss at random when I > floored it... >> With a brand new sequential system I'm sure the twins would be consistent > but as the system gets some age on it, it just seems that its' control of > the #2 turbo becomes less and less predictable, leaving you with about half > the normal "stock boost" and wondering why your twin-turbo car suddenly > feels so slow. Between hardened vacuum lines, leaking vacuum lines, > sticking VSV's, broken VSV's, etc, etc, the system starts to lose control > and leave you without the #2 turbo more and more as time goes by. I also > find that the VSV's are far more prone to failure on cars that aren't driven > very often and/or aren't boosted to the point that the #2 kicks in very > often (If at all), as opposed to those cars that get pushed hard regularly > their whole lives and have actually worked the system's VSV's regularly > their whole lives... It's fixable of course but in the meantime 'till you > find and fix all the problems, the car is inconsistent and frustrating >> to drive if you drive agressively and it's even more frustrating to > troubleshoot as you're finding now... >> >> Although it introduces about 1k rpm more lag, that's exactly why I choose > True-Twin mode personally, even on an automatic's, although on the auto with > the "stock stall" torque converter it ends up being slower in the 1/4 mile > than one with a properly functioning sequential system due to the extra > turbo lag of True-Twin mode but I'm okay with that... >> >> Unless I misunderstood, you were originally getting about 5psi when you > began your troubleshooting process and with real True-Twin you're now > consistently getting twice that so it sounds to me like the turbos are now > both working together as they should be although there still might be a mild > boost leak and it seems to really point mostly to issues with the sequential > system from how I interpreted all your info so far. >> >> What does the car do in True-Twin mode if you ride 1st or 2nd gear up to > about 4,500 rpm's then cruise in that rpm range for like 10-30 seconds, then > go WOT and stay in to to redline, then shift quick into the next gear and go > WOT again? Do you get boost at WOT, is it the 10psi you get in higher gears > above 4k rpm's, and does it hold well and pull strong the whole time and > possibly even spin the rear tires? >> >> Granted I'm at BPU+ in true-twin mode but my 98TT 6-Speed does almost > nothing 'till mid 4k's then turns into a fun little beast and working the > gears to tach up high and have it still be up in the 4k range on shifts > makes my car run strong through the 1/4mi and trap 118-125mph with > consistent 12.0-12.2's and occasional high 11's with crappy 1.8-2.2 60ft's > due to ongoing wheel-hop problems, and I'm not a drag racer at all, I prefer > road courses myself. >> >> I also found that the 93TT auto in True-Twin mode was a slug below about > 35mph but with the auto's gearing, once the tach hit mid 4k's the car always > suddenly lunged and "hauled" for as long as you kept the accellerator down. >> From a stop True-Twin sucked on the auto but at any speed over 35mph it > lunged hard and fast whenever I went WOT... >> Then we BPU'd it and by mid 4k rpm's all of a sudden the car would break > the tires free and get sideways without trac on and with it on the car would > still spin' em and step out and you'd have to steer into it 'till the trac > system kicked in and brought it back in line... >> >> Again, Lance is far better at diagnosing these sorts of things than I am > and he is a huge asset to this list who is very greatly appreciated by > everyone here that he has helped over the years including me, and this post > is just my opinion so far on this topic and I hope it proves to be at least > somewhat helpful for you. >> >> >> Thomas >> myothersupra >> -------------- >> 98TT 6-Speed MkIV >> 93TT Auto MkIV (SOLD) >> 92T Auto MkIII >> 88 5-Speed MkIII >> 84 5-Speed MkII P-Type >> 81 5-Speed MkI >> 01 E-Shift IS300 >> 01 5-Speed ZRX-1200R >> >> --- On Sun, 5/16/10, Arif Khan wrote: >> >> >> From: Arif Khan >> Subject: [mkiv] boost problem (update) >> To: mkiv@mkiv.com >> Date: Sunday, May 16, 2010, 4:43 PM >> >> >> After replacing the WG VSV, I wired up the actuators as outlined in the > tech article on the mkiv site but unfortunately, there was no "ah ha" > moment. Now, instead of building 7-8 psi, I'm getting a consistent 10 psi in > 4th and 5th gear but no boost in 2 - 3 below 4k rpm. >> >> Before doing the above I did confirm that there was pressure in the line > before the check valve on the IACV actuator as well as the lower EBV > actuator. >> >> Furthermore, at the time I installed the replacement turbos I verified > that all butterfly valve operations were smooth and unobstructed. >> >> As of now, I still have to test the pressure tank circuit and the > wastegate actuator on #2 turbo. There is also an actuator on #1 but I can't > get to it without removing the air tube assembly. >> >> Lance - >> While I was searching the mkiv archive I came across a set of posts by you > in which your coils had gotten weak and presented symptoms that appeared to > be boost related. Could this be a similar case? >> >> >> Thanks, >> >> Arif >> sl300gullwing@gmail.com >> >> >> >> >> >> >> _______________________________________________ >> Mkiv mailing list >> Mkiv@mkiv.com >> http://www.mkiv.com/mailman/listinfo/mkiv >> >> >> >> >> >> ------------------------------ >> >> _______________________________________________ >> Mkiv mailing list >> Mkiv@mkiv.com >> http://www.mkiv.com/mailman/listinfo/mkiv >> >> >> End of Mkiv Digest, Vol 85, Issue 13 >> ************************************ > > > > _______________________________________________ > Mkiv mailing list > Mkiv@mkiv.com > http://www.mkiv.com/mailman/listinfo/mkiv > > > > > ------------------------------ > > _______________________________________________ > Mkiv mailing list > Mkiv@mkiv.com > http://www.mkiv.com/mailman/listinfo/mkiv > > > End of Mkiv Digest, Vol 85, Issue 14 > ************************************ From jza80-alfvza at sbcglobal.net Fri May 28 13:46:24 2010 From: jza80-alfvza at sbcglobal.net (jza80-alfvza@sbcglobal.net) Date: Fri May 28 13:46:41 2010 Subject: [mkiv] Re: Re: boost problem In-Reply-To: <7AC62ACB-EA65-443A-A990-17B1BCCEF1C1@gmail.com> References: <201005271700.o4RH03Sm002463@mkiv.com> <7AC62ACB-EA65-443A-A990-17B1BCCEF1C1@gmail.com> Message-ID: <831818.15765.qm@web82205.mail.mud.yahoo.com> The first thing I'd check is the stock BOV. Make sure it seals by trying to blow through either of the big connections with it removed. If air passes, it's toast, and unless you already checked it, I'd bet a lot of money it's leaking like a sieve. I'll take some shots of my HKS BOV install and post them on Club Lexus so you can see how it looks. Mine is definitely in recirculate mode in the OEM spot. lance '93 TT 6 Speed Coupe ________________________________ From: Arif Khan To: mkiv@mkiv.com Sent: Thu, May 27, 2010 11:14:04 PM Subject: [mkiv] Re: Re: boost problem I'll disconnect the wastegate and see what happens. I'm also leaning towards replacing all of the hoses regardless. Fortunately, I replaced the hoses in the back by #2 turbo when I did the turbo replacement. I am in fact running the stock BOV which I put back after removing the HKS SSQV (new) because it was venting to atmosphere. I seem to recall you mentioning that you had managed to install it in the stock location in recirc mode? If so, would you mind sharing some pictures? I'll put back the HKS in the meantime. Thanks for the continuing support. Arif sl300gullwing@gmail.com > ------------------------------ > > Message: 2 > Date: Thu, 27 May 2010 00:36:30 -0400 > From: "lance" > Subject: RE: [mkiv] Re: boost problem > To: "'The MKIV.com National Mailing List'" > Message-ID: <5785DD0B005442FCA902DEF093329944@Wolrab.local> > Content-Type: text/plain; charset="us-ascii" > > Yes, if the wastegate spring is weak it will certainly be a root cause of > low boost, but you wouldn't see 5 psi in second and 10 psi in third. You'd > see either 5 or 10 regardless of gear. Have you tried disconnecting the > wastegate entirely? Just cap the line and cap the wastegate to see if you > can get at least 14 psi. I get 18 psi before the cat becomes the limiting > factor. > > Your BCC setting won't make any difference because you're not hitting 14+ > psi where boost cut occurs. > > I'd be pressurizing all the big pipes - basically capping off the tube going > into the throttlebody, and putting another cap on the outlet of the twins, > then pressurizing to find the leak. You've got to have a big leak somewhere > - like a split hose you just can't see. > > The pressure tank only holds the actuators open when you shift. Its sole > purpose is to provide constant pressure to the actuators through the VSVs so > you don't have constant switching between modes when you shift gears. If it > doesn't leak pressure, it can't cause low boost. > > Are you running a stock BOV? Have you checked it? Tony's car had a stock > BOV with the typical blow through ventilation no matter what. Those things > are junk after the disc inside hardens and shatters. It doesn't take long. > > I did a complete hose replacement on my car. It's a BIG PITA to get to the > hoses on the back of the #2 turbo. I had my gearbox out and the engine > tilted down while I was fixing the leak on the upper oil pan, so I was able > to get to those hoses, but I really don't see any other way to do this > without removing the engine. Seriously, those hoses are next to impossible > to access with the engine and gearbox installed. > > Lance > '93 TT 6 Speed Coupe > > -----Original Message----- > From: mkiv-bounces@mkiv.com [mailto:mkiv-bounces@mkiv.com] On Behalf Of Arif > Khan > Sent: Wednesday, May 26, 2010 11:58 PM > To: mkiv@mkiv.com > Subject: [mkiv] Re: boost problem > > No apologies required, I certainly don't mind it so long as it's relevant. > > I drove the car in 2,3rd gear @ WOT and noticed the boost hit 5psi in 2nd > gear and 10 psi in 3rd gear but it did not break the tires loose. I didn't > stay in the redline before shifting which might invalidate the test. I > think you're right that I probably have some boost leak but not enough to > behave like this. My next steps are the following: > 1. Recheck the bcc setting > 2. Confirm timing > 3. Replace all remaining vacuum/pressure hoses > 4. Check the pressure tank circuit and VSVs > > Although, if the wastegate is weak wouldn't that manifest in symptoms like > mine? > > Arif > sl300gullwing@gmail.com > > > >> ---------------------------------------------------------------------- >> >> Message: 1 >> Date: Sat, 22 May 2010 17:47:32 -0700 (PDT) >> From: Thomas Bradley >> Subject: Re: [mkiv] boost problem (update) >> To: "The MKIV.com National Mailing List" >> Message-ID: <697575.32167.qm@web56607.mail.re3.yahoo.com> >> Content-Type: text/plain; charset=iso-8859-1 >> >> Sorry in advance for the ramblings of this post, I'm just thinking out > loud and passing on some personal experiences with the 3 TT Supras I've > owned over the years, 2 of which started out 100% factory stock when I got > them and both had issues very similar to yours by the time they were 10 or > more years old... >> >> Lance knows a LOT more about these things than most people including me, > but I've owned 2 bone stock TT auto's (drove the first one for over a year > bone stock before selling it to buy my house, and fully BPU'd and > True-Twin'd the second one within a few weeks of buying it due to annoying > random sequential system issues) and my TT 6-Speed came to me with upgraded > down-pipe and cat-back but it was also otherwise stock, and it's been my > experience that with a truly "stock" TT Supra (factory smic and full stock > exhaust) 8-11psi is typical "stock boost" range in warm humid weather (0.6 - > 0.8bar of boost) and in True-Twin mode the boost doesn't really hit until > somewhere in the low to mid 4k rpm range, unlike sequential mode that is a > much smoother boost curve that comes on much sooner. >> True-Twin mode didn't really give me much more boost but what it did was > make the boost far more consistent and the car much more predictable in my > opinion versus sequential that was more like hit or miss at random when I > floored it... >> With a brand new sequential system I'm sure the twins would be consistent > but as the system gets some age on it, it just seems that its' control of > the #2 turbo becomes less and less predictable, leaving you with about half > the normal "stock boost" and wondering why your twin-turbo car suddenly > feels so slow. Between hardened vacuum lines, leaking vacuum lines, > sticking VSV's, broken VSV's, etc, etc, the system starts to lose control > and leave you without the #2 turbo more and more as time goes by. I also > find that the VSV's are far more prone to failure on cars that aren't driven > very often and/or aren't boosted to the point that the #2 kicks in very > often (If at all), as opposed to those cars that get pushed hard regularly > their whole lives and have actually worked the system's VSV's regularly > their whole lives... It's fixable of course but in the meantime 'till you > find and fix all the problems, the car is inconsistent and frustrating >> to drive if you drive agressively and it's even more frustrating to > troubleshoot as you're finding now... >> >> Although it introduces about 1k rpm more lag, that's exactly why I choose > True-Twin mode personally, even on an automatic's, although on the auto with > the "stock stall" torque converter it ends up being slower in the 1/4 mile > than one with a properly functioning sequential system due to the extra > turbo lag of True-Twin mode but I'm okay with that... >> >> Unless I misunderstood, you were originally getting about 5psi when you > began your troubleshooting process and with real True-Twin you're now > consistently getting twice that so it sounds to me like the turbos are now > both working together as they should be although there still might be a mild > boost leak and it seems to really point mostly to issues with the sequential > system from how I interpreted all your info so far. >> >> What does the car do in True-Twin mode if you ride 1st or 2nd gear up to > about 4,500 rpm's then cruise in that rpm range for like 10-30 seconds, then > go WOT and stay in to to redline, then shift quick into the next gear and go > WOT again? Do you get boost at WOT, is it the 10psi you get in higher gears > above 4k rpm's, and does it hold well and pull strong the whole time and > possibly even spin the rear tires? >> >> Granted I'm at BPU+ in true-twin mode but my 98TT 6-Speed does almost > nothing 'till mid 4k's then turns into a fun little beast and working the > gears to tach up high and have it still be up in the 4k range on shifts > makes my car run strong through the 1/4mi and trap 118-125mph with > consistent 12.0-12.2's and occasional high 11's with crappy 1.8-2.2 60ft's > due to ongoing wheel-hop problems, and I'm not a drag racer at all, I prefer > road courses myself. >> >> I also found that the 93TT auto in True-Twin mode was a slug below about > 35mph but with the auto's gearing, once the tach hit mid 4k's the car always > suddenly lunged and "hauled" for as long as you kept the accellerator down. >> From a stop True-Twin sucked on the auto but at any speed over 35mph it > lunged hard and fast whenever I went WOT... >> Then we BPU'd it and by mid 4k rpm's all of a sudden the car would break > the tires free and get sideways without trac on and with it on the car would > still spin' em and step out and you'd have to steer into it 'till the trac > system kicked in and brought it back in line... >> >> Again, Lance is far better at diagnosing these sorts of things than I am > and he is a huge asset to this list who is very greatly appreciated by > everyone here that he has helped over the years including me, and this post > is just my opinion so far on this topic and I hope it proves to be at least > somewhat helpful for you. >> >> >> Thomas >> myothersupra >> -------------- >> 98TT 6-Speed MkIV >> 93TT Auto MkIV (SOLD) >> 92T Auto MkIII >> 88 5-Speed MkIII >> 84 5-Speed MkII P-Type >> 81 5-Speed MkI >> 01 E-Shift IS300 >> 01 5-Speed ZRX-1200R >> >> --- On Sun, 5/16/10, Arif Khan wrote: >> >> >> From: Arif Khan >> Subject: [mkiv] boost problem (update) >> To: mkiv@mkiv.com >> Date: Sunday, May 16, 2010, 4:43 PM >> >> >> After replacing the WG VSV, I wired up the actuators as outlined in the > tech article on the mkiv site but unfortunately, there was no "ah ha" > moment. Now, instead of building 7-8 psi, I'm getting a consistent 10 psi in > 4th and 5th gear but no boost in 2 - 3 below 4k rpm. >> >> Before doing the above I did confirm that there was pressure in the line > before the check valve on the IACV actuator as well as the lower EBV > actuator. >> >> Furthermore, at the time I installed the replacement turbos I verified > that all butterfly valve operations were smooth and unobstructed. >> >> As of now, I still have to test the pressure tank circuit and the > wastegate actuator on #2 turbo. There is also an actuator on #1 but I can't > get to it without removing the air tube assembly. >> >> Lance - >> While I was searching the mkiv archive I came across a set of posts by you > in which your coils had gotten weak and presented symptoms that appeared to > be boost related. Could this be a similar case? >> >> >> Thanks, >> >> Arif >> sl300gullwing@gmail.com >> >> >> >> >> >> >> _______________________________________________ >> Mkiv mailing list >> Mkiv@mkiv.com >> http://www.mkiv.com/mailman/listinfo/mkiv >> >> >> >> >> >> ------------------------------ >> >> _______________________________________________ >> Mkiv mailing list >> Mkiv@mkiv.com >> http://www.mkiv.com/mailman/listinfo/mkiv >> >> >> End of Mkiv Digest, Vol 85, Issue 13 >> ************************************ > > > > _______________________________________________ > Mkiv mailing list > Mkiv@mkiv.com > http://www.mkiv.com/mailman/listinfo/mkiv > > > > > ------------------------------ > > _______________________________________________ > Mkiv mailing list > Mkiv@mkiv.com > http://www.mkiv.com/mailman/listinfo/mkiv > > > End of Mkiv Digest, Vol 85, Issue 14 > ************************************ _______________________________________________ Mkiv mailing list Mkiv@mkiv.com http://www.mkiv.com/mailman/listinfo/mkiv From garybechtold at gmail.com Sun May 30 01:49:44 2010 From: garybechtold at gmail.com (Gary Bechtold) Date: Sun May 30 01:50:01 2010 Subject: [mkiv] Re: Mounting HKS BOV with recirculation In-Reply-To: <201005021700.o42H03ND023850@mkiv.com> References: <201005021700.o42H03ND023850@mkiv.com> Message-ID: <4C020A88.1060005@gmail.com> Here are some pictures I tried to take of the BOV with the recirculation fitting installed. The TRD bar does get in the way of a clear shot. Hope that helps. I could try to take some better ones again. http://s202.photobucket.com/albums/aa311/garybechtold/HKS%20BOV/?albumview=slideshow -Gary Bechtold 1997 Toyota Supra Turbo On 5/2/2010 12:00 PM, mkiv-request@mkiv.com wrote: > Today's Topics: > > 1. Mounting HKS BOV with recirculation (thumps00@gmail.com) > > ---------------------------------------------------------------------- > > Message: 1 > Date: Sat, 1 May 2010 14:47:07 -0500 > From: thumps00@gmail.com > Subject: [mkiv] Mounting HKS BOV with recirculation > To: "The MKIV.com National Mailing List" > Message-ID: > > Content-Type: text/plain; charset=ISO-8859-1 > > I know this has been discussed a little before, but: > > Has anyone successfully mounted the HKS BOV without a flange and used a > recirculation fitting? > > If so, how and where did you mount it? Any pics would be appreciated. > > I can't seem to make it work in the stock location, the fitting sticks out > too far. I couldn't quite find other arrangements that worked. > > BTW, there are smaller fittings that appear to be a better match for the > stock recirculation connection - I ordered a 19mm recirculation fitting off > of eBay. > > Thanks, > Brian '94 TT > > From sl300gullwing at gmail.com Sun May 30 14:30:07 2010 From: sl300gullwing at gmail.com (Arif Khan) Date: Sun May 30 14:30:26 2010 Subject: [mkiv] Re: Mkiv Digest, Vol 85, Issue 17 In-Reply-To: <201005301700.o4UH02di006133@mkiv.com> References: <201005301700.o4UH02di006133@mkiv.com> Message-ID: <4C02BCBF.7040708@gmail.com> Thanks Gary! It appears that the BOV is suspended in place by the inlet/outlet hoses and not the metal bracket. Is that the case? Thanks, Arif > ---------------------------------------------------------------------- > > Message: 1 > Date: Sun, 30 May 2010 01:49:44 -0500 > From: Gary Bechtold > Subject: [mkiv] Re: Mounting HKS BOV with recirculation > To: mkiv@mkiv.com > Message-ID: <4C020A88.1060005@gmail.com> > Content-Type: text/plain; charset=ISO-8859-1; format=flowed > > Here are some pictures I tried to take of the BOV with the recirculation > fitting installed. The TRD bar does get in the way of a clear shot. > Hope that helps. I could try to take some better ones again. > > http://s202.photobucket.com/albums/aa311/garybechtold/HKS%20BOV/?albumview=slideshow > > -Gary Bechtold > 1997 Toyota Supra Turbo > >