| Author | Message | |||||
     Richard Treacy Grand Master Username: richard_treacy Post Number: 2526 Registered: 4-2003 |
I suspect on my Conti R, as does another Forum member with his Turbo R, that the transient boost (TB) is not functioning. Both cars bomb along, but that feeling of an extra whack for a few seconds when wringing the neck is not entirely there. My own early injected Turbo R (no TB) feels no less urgent that the Conti or that Turbo R with TB. My TB is the as-delivered setup triggered by the TPS potentiometer. I have had issues with the TPS, but they are solved, so the TB ECU is receiving the correct signal now. I suspect an electrical connection somewhere and shall work through that. On the Turbo R with TB, a 3-speeder smoothie, the TB is the factory kit retrofitted by Yorks. It presumable works from the TPS (switch) kickdown contact, but the same suspicions about bad connections or possibly a bad solenoid apply. Questions: What is the operating voltage of the TB solenoid – is it simply 12V ? If so, I shall see if it works by applying 12V. Are any particular plugs-sockets notoriously weak ? Any other hints on diagnosis ? If able to confirm that the TB solenoid functions electrically and pneumatically by applying 12V (?), I would then patch a test lamp in the cabin to the solenoid and go for a thrash. Any comments would be most welcomed !! RT. | |||||
| James Feller Prolific User Username: james_feller Post Number: 187 Registered: 5-2008 |
if the bloody weather would improve i'd take the car for a cruise and test the 'JF rectifications', that involved carefully unclipping all related (or at least what I was told were related) electical plugs near the top of the drivers side rocker cover, liberal use of a fine brush and WD40 to ensure all connections were 'connecting' at least those I could easily get at. There are of course two lagging covered connections below the manifolds that seem to plug into solnoids on each side of the engine wall. These are on each side of the engine for TB cars. These are only accessible from underneath and were pointed out to me when car was on a hoist. I have yet to get at these but have been told these can be the culprits for TB not 'boosting' as it should. These and no doubt a myriad of other possible connections buried deep in the valley top of the engine. So easily accessible of course!!!! Ill let the forum in on what I was told by the mechanics who actually fitted the system to my car many many moons ago. It should be absolutely noticable when TB is operating. It should come alive just after kickdown is engaged and last for 10-15 seconds when full power is wanted by keeping your foot planted to the wilton. It operates just beyond the normal Turbocharged areas of our cars. TB is designed to give that 'bit of extra' urge for overtaking or just a smile inducing whoosh. So both RT and I are very keen to see if we can 'find that bit of extra TB urge again in our cars' My TB issue was diagnosed fairly quickly this last week by the team that installed it back in 1995. The guys told me the cars normal ECU is recognising the TB ECU however an electrical connection somewhere is dialing the TB back and opening the wastgate early and not letting the TB give what it should. These guys told me that when operating properly, TB is indeed far more noticeable than I ever first suspected. "you'd know and smile if it was working' were their words. Given this new information, as I never thought my car was anything but bloody swift for a 21 year old 2.5 tonne motorcar, I doubt very much if it has worked while I've owned the car?? However pact has been made, RT and I are on a mission to find our missing TB! and more importantly, like a phoenix rising from the ashes...ressurect it! We will report all findings to the forum and I'll shut up now, as unlike Richard, I have no idea how to do anything more than what a feebly did as described above. All other insights will no doubt come from the Grand Master and other knowledgable folks on this forum. J | |||||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 2527 Registered: 4-2003 |
Thanks, James, Our cover in partners of crime is blown. I have cleaned the terminals at the TB solenoid and driven a bit with no change, despite the fine Canberra weather. Just now, I have cleaned up the downstream plug and connector located on the RH rocker cover and shall see if there is any change when I blast off for Sydney at 4am. You never know ! Anyhow, if any wisdom may shed some light on my earlier questions it would be great. RT. | |||||
| Lluís Gimeno-Fabra Prolific User Username: lluís Post Number: 167 Registered: 8-2007 |
Hello Richard, You need to apply 12 V to the solenoid and to remove all electrical feed to the boost control valve (at least in #52020, my car with the Motronic 3.3 EMS but identical parallel transient boost to yours). this ensures that full boost is applied to force the wastegate close while no signal pressure is applied to open it. I tested mine and it all works, it boost shortly (seven seconds) to 0.6 bar and then decreases step-wise to 0.4. The difference is certainly easy to see from 3000 rpm. Lluís } | |||||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 2528 Registered: 4-2003 |
Lluis, thank you. That confirms quite a lot already. Our Contis are al;most identical in regards to the Motronic and TB systems. Now I know what to do: . Disconnect and remove the TB solenoid . Test it for internal diode suppression to determine the polarity if any – there may be a diode suppressor . Apply 12V and check that it operates to vent the wastegate control pressure thereby allowing full turbo boost . If OK, refit it and patch a test lamp in the cabin . Go for a thrash and see if and when the solenoid is activated as indicated by the test lamp . If inoperative, start a hunt I may be imagining it, but sometimes the car seems to bolt harder than others on full throttle, so maybe the TB does work at least sometimes. I am just not familiar with an operational TB, and have not driven a Conti or Turbo with TB in a reckless manner before owning one myself. Now, James, I dare you ! RT. RT. | |||||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 2531 Registered: 4-2003 |
I have been kindly sent the fitting instructions from the USA for the transient boost system for 3- and 4-speed cars. It is now in the Technical Library SZ Miscellaneous section: http://rrtechnical.info/sz/transientboostkit.pdf RT. | |||||
| Lluís Gimeno-Fabra Prolific User Username: lluís Post Number: 168 Registered: 8-2007 |
Hi Richard, It will be interesting to read about your findings. I can confirm that the transient boost is really felt at 3000-3500rpm onwards specially, but I can also confirm that it does not always engage. I thought however that this was simply because it should not always engage due to engine safety conditions: indeed I could follow the pressure go up till 0.67 bar, which is scary in these engines. I do not know out of memory what parameters does it read, but I think it knows about knock sensor data amongst others. See you, Lluís | |||||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 2532 Registered: 4-2003 |
Lluis, Would it be possible to post a picture of your A-Bank arrangement (under the plastic cover if fitted) ? Here is James' Turbo R arrangement. To the centre with the hoses strangling it is the everyday boost solenoid, and the goldie thing to the left centre is the TB solenoid. RT.  | |||||
| Lluís Gimeno-Fabra Prolific User Username: lluís Post Number: 169 Registered: 8-2007 |
Yes, I'll try to do it this evening, as the car is in the office. | |||||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 2533 Registered: 4-2003 |
ps: I am sure that the motor would be very relaxed with 0,8 Bar provided the Lamerholms (knock sensors) are both in good shape. RT. | |||||
| Michael Hicks Experienced User Username: bentleyman22 Post Number: 47 Registered: 12-2011 |
How did you Get the car in the Office ? | |||||
| Michael Hicks Experienced User Username: bentleyman22 Post Number: 48 Registered: 12-2011 |
Looks a bit Dusty give it a clean | |||||
| Lluís Gimeno-Fabra Prolific User Username: lluís Post Number: 172 Registered: 8-2007 |
through the door :-) | |||||
| Lluís Gimeno-Fabra Prolific User Username: lluís Post Number: 173 Registered: 8-2007 |
Hi Richard, This is the picture. I hope it works. Indeed I can confirm that the TB solenoid closes the waste gate for a while, that is all, the 0.67 bar that I read are just the dump valve release pressure, so everything is working. What makes you think that this thing can withstand 0.8 bar??? Best regards, Lluís  | |||||
| Lluís Gimeno-Fabra Prolific User Username: lluís Post Number: 175 Registered: 8-2007 |
May be this is better, as before, folder is the TB solenoid, black by the elbow is the boost control valve.  | |||||
| Paul Yorke Grand Master Username: paul_yorke Post Number: 847 Registered: 6-2006 |
Not sure if you've got this, but just in case.
I've never been convinced by it! :/ | |||||
| Lluís Gimeno-Fabra Prolific User Username: lluís Post Number: 176 Registered: 8-2007 |
Please excuse the small size of the pictures above. I hope that this is better. Moderator, please delete the older ones as needed.  | |||||
| David Gore Moderator Username: david_gore Post Number: 1102 Registered: 4-2003 |
Hi Lluis, Deletion is not necessary - continuity is a more important consideration for new members who will read this thread in the future. Like our motor cars, our posts will still be relevant and hopefully appreciated many years from now  . | |||||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 2538 Registered: 4-2003 |
Thank you so much Lluis, Paul et al. We're gathering quite some information now. Particularly, why does the system need so much complication to achieve TB ? Surely just one solenoid (the one fitted to all Crewe Turbo motors from the start) could service normal and transient boost limits alike ??? The main thing is that the motor is protected by the knock sensors against catastrophic detonation. That protection remains in the normal boost ECU and is merely communicated to the transient boost ECU. The transient boost is there to utilise the air-to-air intercooler capacity while it lasts (it runs hot after about 20 seconds), whereas on Zytec motors the liquid intercooler (LIC) has a vastly longer time to keep the air cool. Hence, and almost, exclusively hence, the increased continuous power rating of LIC engines. Watch this space. RT. Lluis: ps: the motors are so ridiculously strongly built that they would not suffer at 0,8 Bar or more. The knock sensors will back off the boost of detonation starts. So long as the knock sensors are good, these motors will never explode. | |||||
| Lluís Gimeno-Fabra Prolific User Username: lluís Post Number: 177 Registered: 8-2007 |
Hi Richard, Safety is the main issue in the boost controller, which in as much as I know is derived from a Saab ABT (A for Advanced). I think that being a 1990's set up, the controller just had very little memory available, so a boost curve of 0-0.7 bars was just not fine enough, hence they added a second controller, with a separate map for boosting and de-boosting: having it all in a single controller meant a mesh of parameters that simply was not fine enough. The funny thing in our set-up is that it relies on the Mass Air Flow Sensor for the injection and on a Manifold Pressure Sensor for the boost, operating separately one from the other. The Zytek EMS integrated is all in one controller with only one Absolute Pressure Sensor which integrates both functions. In our cars, you get a Motronic EMS which does not know that there is a turbo under the bonnet (simply measures the suction airflow), and two boost controllers that do not know that there is an engine under the bonnet (simply have a pressure in - pressure out function), their communication is only through the rpm signal and the knock detectors, otherwise they are independent. The advantage of our system however, is that you could (in case you wanted) buy a modern programmable boost controller and map it extremely finely to your needs and driving conditions. I have a confession to make, which is that I have driven the car in close cycle boost (0.67 bars max with my dump valve) and it does feel very very light... of course in a not to hot not too cold day with nice petrol. Phantom Motor Cars however have a nice picture in their website of a turbo R with a modified dump valve and a hole in a piston, they were blowing (I think) at more than one bar and the fuel system could not cope... A final note, I have driven rather hard (bloody hard) a Zytek Continental R... by no means is it any faster than mine, but it does feel lighter at lower revs and most important of all and as you say, the intercooler is just much much better. In our cars you really, so to say feel "the weather", the intercooler is just tiny, which is only justifiable because of the low boost levels. Maybe an specialist could make a bespoke intercooler in case somebody wanted to re-map boost. Best regards, Lluís | |||||
| James Feller Prolific User Username: james_feller Post Number: 188 Registered: 5-2008 |
Dick Treacy and Sherlock Feller will investigate all this TB tom foolery tomorrow and report. Lius thanks for the photos and explanations, I had a devil of a time trying to find a good clear engine bay picture of later TB installations, there just wasnt one i could find on the internet. My own Turbo R is an 89 car fitted with TB by Yorks 5 years after it was delivered in Aus. It seems we can now conclude that 'goldie', thats what RT and myself are calling the Transient Boost solenoid, not to be confused with the BLACK boost control solenoid that will of course be on all Turbo cars, is the quickest visual clue in the engine bay! Richard he who dares wins! J | |||||
| James Feller Prolific User Username: james_feller Post Number: 191 Registered: 5-2008 |
ohh I also forgot to say that LLuis thanks for telling us the rpm range that TB is supposed to work in too! thats very handy to know and I will be testing this tomorrow morning when driving to Sydney. In the terrific document that RT got hold of it states that TB raises boost to 9PSI holds for 3 seconds and then gradually ramps down over 7 seconds to normal boost of around 6PSI. So in theory this is fairly significant and you should notice this I would have thought. Indeed ill be testing tomorrow. Typical that it works 'sometimes' and not others...dare I say it...bloody english cars... | |||||
| Lluís Gimeno-Fabra Prolific User Username: lluís Post Number: 179 Registered: 8-2007 |
After so much difficulty finding a decent picture, here comes another one, from the other side. The Zytec arrangement is completely different, by the way.  | |||||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 2545 Registered: 4-2003 |
Lluis, As you note, the Motronic and boost systems are somewhat independent. I am trying to be sure of the function of the pressure transducer to the Motronic. I assume that it tops up the fuel input to account for boost. In that case, I assume that the Motronic can handle in excess of 0,6 Bar as needed during transient boost without modification. In other words, both the pressure transducer and Motronic can read and process pressures of up to, say, 0,7 Bar ??? Do you know if that is correct by chance ? If it is correct, as suggested by the fitting instructions for the upgrade kit, then I have ideas about implementing TB on Motronic cars in a far simpler and safer manner than by using the factory or third-party aftermarket kits available on the market especially for these cars. Thanks, and thanks for the pictures ! RT. | |||||
| Lluís Gimeno-Fabra Prolific User Username: lluís Post Number: 180 Registered: 8-2007 |
The Motronic 3.3 has an absolute (barometric) pressure transducer for the Engine ECU and the manifold pressure transducer, but isn't it only for the boost controllers? I may be wrong, but I think that the only pressure signal going to the ECU is the barometric pressure signal for altitude correction. With my new computer I cannot still read (as I used to ) IETIS, because it's an apple (no I did not choose it). But I think that the calculation of the engine ECU is based on airflow and not boost pressure. A final note and question. making a turbo blow harder only makes sense when the intercooler can cool the stream to acceptable levels. I thought of having an adjustable bleed valve (there are very good ones in the market) and a real manometer to see what is it like driving with 0.7 bar max constant boost, but would you dare doing this in a hot summer day? In other words: I fear that to play with boost safely, we would need a much more developed intercooler system. The fuel system is probably so over-dimensioned that it can handle a lot more boost, but what about the air temperature and pre-detonation? Being a fool, I can however confirm that driving with max boost on part throttle -with the boost control signal disconnected- does feel nice :-) | |||||
| Lluís Gimeno-Fabra Prolific User Username: lluís Post Number: 181 Registered: 8-2007 |
Oh yes, Motronic 3.3 (as in 1994) is taken directly out , including 88 pin connection from BMW E32 four litre V8, which did not have boost. I think that it's two really independent system that we have. Which in a way is fascinating and in a way is weird. But the fuel correction for boost would be done automatically with the increasing airflow, no need to measure boost pressure. It's not the most sophisticated of systems, but it makes sense when you cannot develop your own integrated EMS/boost controller system. Lluís Lluís | |||||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 2546 Registered: 4-2003 |
Lluis, I'll check that the M3.3 has the dual identical pressure transducers (and sort out IETIS with you privately). Certainly the earlier systems have two identical transducers piggbacked: one for boost and one for the Motronic. The first injected cars without intercoolers have just one transducer to feed the boost and KE Jetronic in parallel. There is a service bulletin for those cars to have a second transducer fitted, making the KE2 and the boost fed by independent but equal boost/depression signals, so maybe a few early injected Turbo Rs blew up ?? The KE2s and early Motronics have the transducers strapped to the cruise control actuator, whilst later cars have them back-to-back next to the Motronic ECU under the RH plastic underbonnet cover. The TB system relies on the knock sensors to cut boost when dangerous. The standard boost ECU apparently communicates knock sensor status to the TB ECU. Whilst I would not tempt fate for long at 0,7 Bar, in theory the motor is protected. The knock sensors drop the boost as much as is required to stop damage. For example, on cheap 92 RON fuel and with our high 8:1 compression ratio motors, you cannot exceed about 0,35 Bar with a cold intercooler then 0,31 Bar continuous without the knock sensors limiting boost, normal or in transient boost mode alike. Yes, I may consider a liquid intercooler sometime, but at present transient (over)boost would be enough. The air-to-air intercooler is safe enough without becoming too hot for the standard system of 5-10 seconds at 0,6 Bar I am sure, but I have always had reservations about driving with the knock sensor limits stopping a motor explosion !! So, no, I would not do the 0,7 Bar test for more than a couple of seconds at most without instrumentin the motor as a research exercise !! RT. ps: the ultimate would 4,8:1 compression, 1.2 Bar boost and a whopping liquid intercooler !! | |||||
| Stefan Morley Grand Master Username: myupctoys Post Number: 355 Registered: 7-2009 |
Hi Guys, There are really three independent systems. One regulating boost with the wastegate based on the knock, RPM and Manifold pressure inputs, one dealing with the fuel flow based on the RPM, Manifold pressure and TPS and the final a mechanical constraint in the form of the dump valve purely based on pressure. It has the final say so in the Max boost based on the spring pressure. Some ways a good backup being independent, all else failing it conserves the engine. 4.8:1 1.2 bar :-) Stefan | |||||
| James Feller Prolific User Username: james_feller Post Number: 192 Registered: 5-2008 |
ok, Richard and I tested 'my rectifications'. We can both report that we are of the same opinion. My TB is not working or there is no magical whoosh other than the the normal boost and swift sailing the car already has. Richard would agree with me I sure that my Turbo R feels decidedly swift and composed at any speed but macigcal TB....it is just not there. We then took RT Turbo R for a drive and its clear what no cats, no emissions and no air pump provide. RT 87 Turbo R with no pollution or cats certainly feels more eager and just more urgent than my 89 car. So we have a challenge, We must find out why my TB has decided not to!!!! J | |||||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 2556 Registered: 4-2003 |
So the plot thickens. It turns out that TB is just a desperately-implemented mechanism to bring CAT cars (like Australian-spec 1988-onwards cars) only barely to the same level of boost as non-CAT cars, but only for 6-9 seconds. TB must have been introduced after many customers were really annoyed that their updated new cars were gutless compared to the early Mulsanne Turbos and the first injected 20k Turbo Rs (all UK-only deliveries, none in Oz etc). OK, with TB the CATs hit 600 mBar for a short transient to catch up, then drop to the 420 intermediate transient, exactly the same boost as non-cats have continuously, then drop to a pathetic 310 mBar continuous. That’s why my Turbo R walks all over my Conti without TB. Yip. Here comes a TB modification for cars which don’t have the 8-grand TB kit installed. Watch this space. RT. | |||||
| Lluís Gimeno-Fabra Prolific User Username: lluís Post Number: 186 Registered: 8-2007 |
Believe me, This space will be watched... | |||||
| Lluís Gimeno-Fabra Prolific User Username: lluís Post Number: 187 Registered: 8-2007 |
Richard, If the point is to increase boost whilst keeping the safety, why not just have a good quality bleed valve trimmed to 0.65 before the wastegate actuator? | |||||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 2558 Registered: 4-2003 |
Lluis, I have developed an add-on control unit which I think is safe. Although the dump valve gives pressure limitation, it does not protect against detonation. Important is to preserve the functioning of the knock sensors at all times to avoid damage. I do it all through the main boost ECU system without changing the wastegate, without a special transient boost ECU, no new transmission ECU, and without adding another solenoid valve. Those bits are in the Factory kit, but I wonder why as they cannot improve reliability. Like the original system, my prototype has three modes: • A brief 600mBar boost (1613 mBar absolute) for three seconds, then • 420 mBar boost (just below the 430 non-Cat continuous level) for another 6 seconds, then • Standard Cat-equipped level of 320 mBar (vs 430 on non-Cats) continuous thereafter. • No subsequent transient boost until the system has been in normal mode for at least 30 seconds I’ll test it with instrumentation before publishing it all. RT.
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| Lluís Gimeno-Fabra Prolific User Username: lluís Post Number: 188 Registered: 8-2007 |
Hoi again, Excuse my question, but, what is the difference between what we have, and what you have developed? I mean, you already have TB ECU, do you plan to just disconnect it? Lluís | |||||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 2559 Registered: 4-2003 |
Lluis, I have no TB !! That was the surprise. Although the manuals show my car, chassis 42592, has TB, it does not. All I am intending to do is to implement it, and see no reason to replace the wastegate, fit a fancy ECU and an extra solenoid valve. I see a simpler and safer way to do it. RT. | |||||
| Lluís Gimeno-Fabra Prolific User Username: lluís Post Number: 189 Registered: 8-2007 |
OKOKOK Some posts ago there was general confidence that with Knock detectors operating properly (and the EMS should detect and report any failure) there was no danger raising boost to 0.6 bat constant. 3 seconds is very much nothing... and what's more, what I am actually after is more boost at mid-throttle, not at just full throttle when Armaggedon seems to be awake under the bonnet. I have more than once played with the idea to fit a parallel turbo management system (means just a parallel solenoid) that is fully programmable. With your modification, can you just raise the boost curve of your controller to 0.6 bar? Best regards, Lluís | |||||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 2561 Registered: 4-2003 |
Lluis, Yeas, I can change all the parameters. That includes the 600mBar sertting, intermediate 430mBar setting and all the timing factors including delay between TB applications and TB durations.. I have done it all in hardware, and have my prototype on bench test this minute. Once I am confident, I shall try it on the car. As with the factory system it fiddles with the MAP signal once you hit full throttle. However, I believe it more robust and fail-safe than a system reliant on microprocessors. I’ll keep you posted. RT. | |||||
| James Feller Prolific User Username: james_feller Post Number: 196 Registered: 5-2008 |
Gents, I'd have to agree with Llius, RT. TB would be much better in the early to mid section of our torque curves we all have in our turbo bentleys rather than "arrmageddon' (wonderful term Lluis ) at full throttle and very high speed.... Lets face it, the most times you need TB or good solid boost is never really at 200klm per hour on a motorway....its more advantageous at 80 - 100klms overtaking up a hill or moving past and around slower traffic would you agree? I want solid power to move and negotiate the 'Big leviathon' safely in this rev and speed range rather than at 180- 200klms which I never do of course..... My 335 Beemer has the turbocharging system perfected in my opinion. Boost whenever I want it and controlled, sure it has 2 turbos so as one is winding back the other is coming in thus it accelerates as progressively and with that same 'aircraft on takeoff feel' as the Bentley, however its far more swift of course. The Bentley I will give compensation to as its 22 years old, twice as heavy as the BMW and in comparison to BMW, Bentleys handling is light years apart.... That said, the Bentley doesn't suffer from any noticable turbo lag, it always delivers that wonderful grunty power in a smooth and refined way. I would like TB at much lower revs than 3-3500rpms though. Much better and far more usable in the 1500-2500 rmp curve I reckon. RT interested in your experiments when done. Drop me a line when youve played and tested and ill supply the Hunter Valley red! J | |||||
| Lluís Gimeno-Fabra Prolific User Username: lluís Post Number: 190 Registered: 8-2007 |
Hi James, The latter Zytek system that a friend of mine has in his Continental R has exactly this feeling of being "lighter" without being faster. In my opinion is boost control and indeed, in many days a much better intercooling. I will do probably parallel experiments with a good quality mechanical bleed valve and report. Best regards, Lluís | |||||
| James Feller Prolific User Username: james_feller Post Number: 197 Registered: 5-2008 |
OK, I have one word to shout... REMARKABLE!!! It is indeed remarkable what an overall transformation this Richard Treacy modification has acheived on my 89 Turbo RL (new wiring relays and mapping). I will leave the figures and boost control stats to the grand master to espouse as I have no real expertise in this area other than keen fascination and amazement in what was achieved in real driving terms on my car. I will attempt to explain it however RT may have to correct some of my statements if they are inaccurate wrt the engineering that went into the project. This project stared on monday this week. 1. A boost guage was fitted to my car to assess the boost prior to rectification. It was found that indeed I was only getting about 3psi or 160mb of pressure, pathetic in general terms of what the system is safely capable of. 2. As an expirement ONLY, we then removed the 2 Boost hoses from the Boost solenoid ( BLACK unit we all have on our cars ) to see if the mechanicals of the system were correctly functioning. We drove the car with boost guage attached and 600mb 9psi was reached easily and quickly on flooring of the throttles. WOW WOW WOW! my god is it wonderful to expirence this! immense acceleration though not unsafe at the least, we were on wide back streets but could not do much more than 0 -80klm sprints unfortunatley. I run only 98 octane and while yes the knock sensors were bypassed for this test it was perfectly safe. These hoses were then reattached ( unfortunatley...  boo hoo) 3. RT and JF then installed the simply engineered wiring from the exisiting installation. It took about 30 minutes or so and looks neat and frankly you would not pick it in the engine bay. Ill upload some photos soon Lluis and Stefan so you can see. 4. We then tested the car and found that 160mr had risen to around a reliable and constant 300mB or 6psi on boost guage on test driving. (This transformation while on paper is impressive only restores what the car had when new. My transient boost should come alive ontop of this as you would be aware) This leads me to believe that most of our cars these days are probably woofling around 'way down' on their true performance capabilities due to ageing wiring and electromagetic inconsistances wrt to relays and solenoids simply ageing....like we all do I suppose. RT made a comment to me that the wastegate is now starting to get the 'message' and operate as it should! Indeed it is ! Now comes the paragraph I can wax lyrical about. I had a chance to drive the car on good open roads last night on my way from Sydney to Mudgee ( it was very wet and rained constantly for 3 hours so no silly driving was undertaken ) However as I stated to RT, real world drivability is there aplenty. What I mean by this and is repeatable time after time. An expirement and what I was able to do was 120klm at 2400rpm up long meduim to steep gradient hills. The car held 2400-2500rpm sustained 120klm constantly. This test speaks volumes in my opinion as it was the 'hidden and revived' boost providing the power, NOT increased engine rpms as would have been the case last week. What I mean is the car did not need to be accelerated to 2800-3000rpm to sustain the same speed on the same hills as it did last week. Takeoff around town is more eager, though not much more than it used to be, but this to be expected as boost was there at lower rpm. The difference is 2000-3500rpms. I feel it at say 80klms - 140klms, a minor dab on the throttle and the car instantly gets the boost performance it has and is off!!! Rather than a week ago, while I dont believe my car was slow... it felt a bit 'lazy', I was using near full throttle to acheive the same range. In effect we have managed to double the boost performance ( or restore it to what it was from factory ) so the car is now using boost effectively, accurately and everytime reliably! MARVELLOUS. Our next challenge on my car is TB. We are both of the opinion that 'maybe' in the first instance with good electronics and electromagnetic connection reestablished on my car....it may come good in time. I will monitor and test this over the next few weeks to see if I can exercise my 'wastegate and TB solenoid'!!! Now that I do know what im feeling for re transient boost ( remember we expirenced 9psi or 600mbar when removing the boost hoses on black solenoid) it may 'come good' of its own accord now that reliable current, instructions and conditions are being supplied to the normal boost system. Stay tuned.... Now there are plans a foot for TB in its own right but that I will leave to the grand master, I know hes open to offers!!!! RT, its amazing what has been achieved wrt to my car. RT, a big thank you!!! This leads me to state that as there are so few of our turbo cars around, its our custodial duty to get them powering again!!! awake the giants from their slumber...and for their age now, what amazing and lovely machines these cars are to drive and to experience TURBO magic again.....wonderful! More to come soon. J | |||||
| James Feller Prolific User Username: james_feller Post Number: 221 Registered: 5-2008 |
ok, my TB system works statically but dynamically its a bit hit and miss....damn. What I mean is Rt and I found that the kickdown relay was a bit hit and miss....this is fixed and we can now hear TB solenoid klicking in when fulling depressing the accelerator now so the system works as its designed to do. However when we are driving we suspect the knock sensor settings maybe a bit sensitive and knock it out after a second or so... as it gets to 6psi and thats alll we get....We have put a test light on the TB solenoid and can see its getting signal but it stays on for a breif second or so and flicks off.....but car is going beautifully!!!! so the plot continues to ressurect my TB, its coming!!! J | |||||
| James Feller Prolific User Username: james_feller Post Number: 231 Registered: 5-2008 |
so, what to do.... we disconnected the TB ECU Module and 'cleaned up the pin connections on both ECU units behind the front lights (to be honest the connection terminals were pretty clean but nevertheless they got a good clean up and wd40 ). Once and once only the system worked exactly as it should, 10 seconds the test light was on for. I think the word F==K was muttered by both 'lunatics' and smiles abounded. Howeverwe could only get the system to do it once 'dynamically' and then it would not do it again. Just to refesh, the system works perfectly when static. However will not work as designed when dynamic. It simply builds presuure to 6psi and the test light flicks out....ie will not force the system to 9psi as its designed to do. We are now out of ideas about the orginal system, we can of course bypass this system and retrofit 'RT system' to give the car TB but it would seem a shame to do this as the crewe system is inbuilt. Does anybody have some ideas for us? Remeber we have kickdown working, test lights for TB are working, Knock sensors are new and clearly working so I am unsure of what is going on now, could the TB ECU have a weak link? perhapes the knock sensors are a bit sensitive? has anyone else some suggestions or exprience? Its my mission to try to get this very 'NAUGHTY' TB system working....currently its on detention and in disgrace, it gets a stern talking too on regular occasions and still refuses to behave!! J | |||||
| Lluís Gimeno-Fabra Prolific User Username: lluís Post Number: 273 Registered: 8-2007 |
Hi you both, Has it occured to you that the system might be working as intended... but that the Knock protection may be waaaaay too conservative? I am positive that the system in my car is working exactly as it is intended to (you really feel the TB coming as an extra boost at full gas without kickdown), however I can assure you that it did not do it during holidays when the ambient was 30°. The question then would be, how on earth do you tame the Knock protection and do you want to? I have purchased a 25K pot and resistances and will try the next set-up, maybe this week. See you, Lluís | |||||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 2679 Registered: 4-2003 |
Hallo again Lluís, One aspect that we have considered is that the knock sensors are just a bit weak: OK for the boost control ECU (TCB) but too weak for TB ECU (TCT). James’ normal boost behaves perfectly at all temperatures. On my Conti R, when very hot the knock sensors were playing up so I replaced them a while back when relocating the solenoid valve and fitting a ceramic solid-state relay. That system is consistent now, and my home-made TB ECU is working just fine thank you. As to altering the knock sensitivity, it is easily done: turning the K potentiometers inside the Boost and TB ECUs clockwise makes them less prone to cutting boost prematurely, but I am reluctant to go that route before everything else is exhausted. I would want to do some detailed bench testing of a TB ECU before making a new K setting, and that would take some setup with signal generators and the like. Any tips on what we may be missing on James' TB would be most welcome indeed. Incidentally, a number of lazy Turbo Rs have popped up in Australia low on power. It seems to be an issue with every such car I have seen except for my Turbo R so far. They are responding nicely to the package of treatments to the delight of the owners. Just today one with TB was rectified, restoring both boost and TB, scaring the wits out of the owner. Similarly, one last week without a TB kit responded so well that the owner is astonished. RT. | |||||
| Lluís Gimeno-Fabra Prolific User Username: lluís Post Number: 274 Registered: 8-2007 |
But aren't you naming the cause yourself? In case the TB disconnects dynamically but not statically, the Knock sensors are wrong or the sensitivity of the ECU is too high. APT and CPS are giving the right signals (unless the APT is not responding in the high range, but this would be unlikely). There are no other signals which are operating dynamically but not statically. I guess the Knock sensors are just the screw-in typical Bosch items (only one model exists, I think. So that should not be a difficult cause to track. Am I not seeing anything obvious? TPS dymanically and statically same Ignifion dymanically and statically same CPS gives rpm, so should be fine. APT, only in case it plays up from 0.4 bar could it be disconnecting the system. Knock, Only in case it over-amplified the signal could it be disconecting the system ECU, are you sure the sensitivity is identical in all ECU's? | |||||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 2680 Registered: 4-2003 |
Lluís, The knock sensors are not the usual Bosch type. There may be a Bosch equivalent, but I have not seen one. The closest I have seen is applied to Honda motors, but I am not sure whether they are Bosch units or not. The Bosch ones I know on Saab, BMW etc are fixed by an M8 bolt, whereas the ones on our cars have an M12 Fine stud which screws into the cylinder block just under the exhaust manifolds where they become mighty hot. They look like a spark plug, and a standard spark plug spanner even fits them albeit a little loosly. The issue with these broadband knock sensor types,(as opposed to the older-style tuned types), and this applies to both the Crewe OEM Lamerholms and the more common Bosch ones alike, is that they must detect low-frequency noise loud enough for the ECU to recognise it. If the noise is too low, then the ECU shuts down when there is engine RPM assuming that the knock sensor is faulty. That low-frequency noise is the normal engine noise: 2 pulses per revolution for each 4-cylinder cylinder bank and clatter from valve gear etc. If there is enough low-frequency noise, then the ECU engages until there is sufficient higher-frequency noise (2kHz upwards) to indicate detonation. Concerning the other signals, of course they may be present in one (Boost ECU or Motronic) system but disconnected or otherwise absent from the other (TB ECU) by poor connections or a faulty TB system., We have tried what we can but will try harder. RT. | |||||
| James Feller Prolific User Username: james_feller Post Number: 232 Registered: 5-2008 |
hi LLuis! glad to hear from you. RT's point is exactly that, we are not sure yet in my cars case that the sensitivity is too conservative. I personally feel that my knock sensors could still be saying 'no no' and simply cutting TB. Your post describes exactly the behaviour my car demonstrates....all works perfect with the system with the car parked, however get the car on the road and try to get it to 'Transient boost' and TB is shut off in a second. My knock sensors are not Bosch LLuis. They are the Lamerholm originals. cleaned up and new terminals for sure but still the original lamerholms. we will try some other alternatives soon to rule out 'sensitive knockers'. RT is 100% correct, it seems quite a number of Turbocharged cars, people must read this forum, are 'popping' up here in Aussie land with lacklustre and poor performance, the 5 I know of have been quickly sorted out now. I can report that a few owners were actually thinking of 'selling their turbos' believing the cars were nice but not really that 'powerful' compared to modern cars these days....well I can confirm the owners are not only delighted and astonished at what their cars will do after being rectified but have absolutely no intention now of selling them. This is the best news and feed back as far as Im concerned. As for my missing TB, we are working on this, it will come and we will solve it, of that im sure. At any rate I should not complain or be that upset....I get a boost guage measured 6psi or 420mlbars and 0-100Klms in 6.5 seconds, ahhh not too bloody bad really for a 22 year old Turbo RL huh.... J | |||||
| James Feller Prolific User Username: james_feller Post Number: 233 Registered: 5-2008 |
just to be clear...its not really my 0-100klms time that worries me that much, TB is not going to improve my 0-100 time very much. What TB will do is give me faster ramp up to full boost for 3-4 seconds, in that critical 80-120klms speed range to make that 4th car that much easier to overtake while casually adjusting the stereo.... Prat 1 over and out for tonight... | |||||
| Lluís Gimeno-Fabra Prolific User Username: lluís Post Number: 275 Registered: 8-2007 |
Hi people, Richard, did you replace the Lammerholms with Bosch units? In that case, how did you build an adapter? Best regards and thanks. Lluís | |||||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 2681 Registered: 4-2003 |
Yes, I made an adaptor for the physical fitting of each of the Bosch knock sensors, but fortunately the electrical connector is identical. Mind you, a new plug is almost imperative to fit under there even if it is a pain to install it. The Lamerholm VP50/1 is no longer in production, so I fitted a pair of new Bosch knock sensors as I wanted to have new sensors. The Lamerholms seemed OK most of the time, but I had doubts as to their functional repeatability. Lamerholm has given up producing these devices, so all sensors on offer from Crewe are of limited supply. The Bosch ones I have chosen have the exact characteristics required, so will match the specs. These Bosch knock sensors are applied to many new vehicles on sale today. What is more, the Bosch units, by virtue of their shape, avoid the severe heating by the downpipe-cat that ruins the Lamerholms. RT. |
