NB-V70R Posted February 11, 2016 Author Report Share Posted February 11, 2016 So many of you have probably seen my question in the tuning thread, but as it was deemed to probably not be tuning related, I will continue the conversation here. The problem is that my boost onset has been too slow for what is expected from a TD04-16t ie. peak is around or after 4000 rpm. I feel like the boost should be hitting a lot sooner than that. If anyone has ideas about what the problem might be please share. The existing thoughts thus far have been: -Improper Wastegate Adjustment (disabled wastegate and boost onset was still slow until 3500 rpm so this probably isn't the sole reason) -Small Misfire in very low rpm preventing spool -Worn Turbo (136,000 miles) -Torn CBV? (not sure if this would cause such an issue, but I am trying to push 18psi through the stock one. It is on the list to upgrade soon anyway) Quote Link to comment Share on other sites More sharing options...
lookforjoe Posted February 13, 2016 Report Share Posted February 13, 2016 If the cbv is blown, it cannot create positive pressure, since until there is sufficient volume / pressure to negate the leakage and some to continue to the intake, it will simply dump back into the intake side of the compressor. You need to remove the diaphragm and flex it looking for cracks. Back pressure is required to create intake pressure. So cam timing, manifold leaks, etc all play a part. This is all very basic stuff though - Live & learn - all this should have be checked from the start. Stage 0 really. Quote Link to comment Share on other sites More sharing options...
NB-V70R Posted February 13, 2016 Author Report Share Posted February 13, 2016 9 hours ago, lookforjoe said: If the cbv is blown, it cannot create positive pressure, since until there is sufficient volume / pressure to negate the leakage and some to continue to the intake, it will simply dump back into the intake side of the compressor. You need to remove the diaphragm and flex it looking for cracks. Back pressure is required to create intake pressure. So cam timing, manifold leaks, etc all play a part. This is all very basic stuff though - Live & learn - all this should have be checked from the start. Stage 0 really. So, since I am still hitting peak boost, I shouldn't worry about the diaphragm? My thinking was that, at some point, a tear can only flow so much through it; therefore, boost would still develop, but later than usual. I really don't want to take out the CBV without removing the turbo just to inspect it. I have heard of what a PITA that job it is to do with the turbo in and the angle gear on. If I can assess its condition just by behavior, I will attempt to do that first. I am going to try adjusting my wastegate actuator tomorrow and see if I can improve on my issues. I will report back later with anything I come up with. I have been meaning to go through and document all of the settings such as cam timing to create a spreadsheet that I can reference in the future. I am hoping everything is correct now, but as you said this should have been checked earlier. Living and Learning seems to be all I do nowadays, but that isn't a bad thing I suppose.Thanks for the advice! Quote Link to comment Share on other sites More sharing options...
lookforjoe Posted February 14, 2016 Report Share Posted February 14, 2016 A CBV that is partially leaking would possibly cause delayed total boost, that was my point. If it's blown, obviously, you wouldn't be making any boost. The CBV is accessed from the top - not below, so no messing with the AG, etc. small ratching 10mm wrench is about the easiest way to get the lower bolt tucked out of the way. Been years since I dealt with a stock turbo so I don't recall if the Turbo outlet pipe needs to come off. Quote Link to comment Share on other sites More sharing options...
Midnight Caller Posted February 14, 2016 Report Share Posted February 14, 2016 (edited) You can do the inspection simpler. Just connect the boost gauge to the CBV, and floor it a little. Remember your boost onset start, and the approximate boost vs rpm you have prior to doing this. Then just look at the boost gauge, if it starts raising when you hit the throttle, there you go, your CBV is teared up. That's what happened to mine, I never reached 15PSI on my 16T and lo and behold, after 4000rpm the CBV leaked almost 5 or 6 PSI ! You could reach max boost but the turbo is and TCV are struggling to maintain it. Edited February 14, 2016 by Midnight Caller 4 Quote Link to comment Share on other sites More sharing options...
NB-V70R Posted February 14, 2016 Author Report Share Posted February 14, 2016 6 hours ago, Midnight Caller said: You can do the inspection simpler. Just connect the boost gauge to the CBV, and floor it a little. Remember your boost onset start, and the approximate boost vs rpm you have prior to doing this. Then just look at the boost gauge, if it starts raising when you hit the throttle, there you go, your CBV is teared up. That's what happened to mine, I never reached 15PSI on my 16T and lo and behold, after 4000rpm the CBV leaked almost 5 or 6 PSI ! You could reach max boost but the turbo is and TCV are struggling to maintain it. Ahh good tip! I will try that and see if there are any issues there. Thanks! I went out to adjust my wastegate actuator this morning, but it was very rusted up. I tried to hold the shaft from spinning with a pair of pliers, but the assembly (nut and rod together) spun inside the wastegate diaphragm housing. Now they can do full revolutions. I assume this is not correct and that my actuator is now broken and in need of replacing. Is it normal to have the rod spin or is it attached directly to the diaphragm inside that However, when I took the car out for a drive didn't seem to affect boost pressure or onset all that much. This makes me think that something was wrong earlier than this incident. I am considering just buying the Forge Piston CBV and a Kinugawa Wastegate actuator. They can be used later on in the build as well as right now so I think it is a worthwhile investment. At least with Volvos (all cars really) there is a really simple formula to budgeting: More $$ = More Have a great day everyone! Thanks Quote Link to comment Share on other sites More sharing options...
Midnight Caller Posted February 14, 2016 Report Share Posted February 14, 2016 (edited) My actuator rod also spun in the actuator housing when I tried to adjust it. I stopped that with a grip pliers. Yes, they say it may damage the diaphragm but that didn't happen for me and neither for you it seems. Keep up posted ! Edited February 14, 2016 by Midnight Caller Quote Link to comment Share on other sites More sharing options...
NB-V70R Posted February 22, 2016 Author Report Share Posted February 22, 2016 Sorry for not updating recently. I had to reset my laptop and lost my 18psi tune with all of my log files so I have been rather busy reconstructing those for the past few days. I did manage to tighten my WGA preload and it seems to have helped bring the boost onset slightly sooner in the Rev range. I am a bit worried ( I know, huge surprise) about the elongation of the wastegate door pin hole. It is definitely an oval with a few mm of play around the pin in the actuating direction. This doesn't seem like the way Volvo would have designed it but idk. I will try to snap a pic and post it up later. Quote Link to comment Share on other sites More sharing options...
lookforjoe Posted February 23, 2016 Report Share Posted February 23, 2016 Shoiuld not be any play in WGA barrel end that drops over the WG pin. Get another from any other Volvo unit. Easy enough. Use dropbox to save all you tune related files - that way it makes no difference what happens to your laptop. I had to do this as I was constantly switching between laptops. Quote Link to comment Share on other sites More sharing options...
NB-V70R Posted February 23, 2016 Author Report Share Posted February 23, 2016 2 hours ago, lookforjoe said: Shoiuld not be any play in WGA barrel end that drops over the WG pin. Get another from any other Volvo unit. Easy enough. Use dropbox to save all you tune related files - that way it makes no difference what happens to your laptop. I had to do this as I was constantly switching between laptops. OK will look into a solution. Thanks! Yeah I am definitely going to do something like that going forward for backup at least. It has been good practice and I will do it better this time. I did take fairly comprehensive paper notes as I was going so I can mostly reconstruct from that. Quote Link to comment Share on other sites More sharing options...
NB-V70R Posted February 24, 2016 Author Report Share Posted February 24, 2016 Here is the picture of the wastegate rod end. This looks like excessive play that won't be getting better over time, but I could be wrong. That gap is probably 1.5-2mm. I did remove the locking clip just for the picture. I have been researching the Kinugawa adjustable wastegate actuator for the P80s and I have been seriously tempted. NEU did a great write up when he first got his in 2012: I was looking at getting it to upgrade and replace the current wastegate. I would probably get either the 7.35 or 11.7psi spring. Since I will be sticking with the 16T for a few years, I think this will help make it the best it can be. Any other people on here running these with some thoughts? @NEU What are your long term thoughts on the actuator? Have you had any issues or failures since the end of that thread? Quote Link to comment Share on other sites More sharing options...
lookforjoe Posted February 25, 2016 Report Share Posted February 25, 2016 Think about it. Any play there means the TCV cycling to modulate boost is inaccurate due to that slop. While you're consideirng other options, just grab a barrel end off any other Volvo TD04 turbo.... Quote Link to comment Share on other sites More sharing options...
NB-V70R Posted February 25, 2016 Author Report Share Posted February 25, 2016 1 hour ago, lookforjoe said: Think about it. Any play there means the TCV cycling to modulate boost is inaccurate due to that slop. While you're consideirng other options, just grab a barrel end off any other Volvo TD04 turbo.... OK I will. There is a pick n pull near me that should have one to hold me over for now. Thanks so much Quote Link to comment Share on other sites More sharing options...
NB-V70R Posted April 6, 2016 Author Report Share Posted April 6, 2016 (edited) Alright, I suppose I owe everyone an update (not that anyone is anxiously awaiting this thread), but it has been a while and a bit has happened. Firstly, my A/C finally failed. The culprit was a seized blower motor so I ordered a genuine Volvo one from Tasca. So far, it has been 2 and a half weeks and no package. Apparently, it wasn't in stock and had to be special ordered from the OEM. Can't wait to get that installed, I am hating this NC weather without A/C lol. On the performance side of things, everything is great. I ended up purchasing the Kinugawa wastegate actuator with the 0.8 bar spring, but it included both the 0.5 bar spring as well. I installed the heavier 0.8 bar spring and put the assembly in the car. After installation, I noticed that the rod could not be adjust short enough to apply any preload and instead held the wastegate open by about 1-2mm. Also, the design of the rod does not suit itself to threading further down the shaft, but I made due and cut the shaft down so that the end could be threaded on slightly further. This setup doesn't allow for use of a locking nut so I would like to search for alternative options in the future, but it works for now. Pic of the new WGA w/ shortened shaft: I ran on wastegate pressure for a while and did a few datalogs. The new actuator allows for boost to build much quicker than with the worn factory wastegate. The car feels like it should have before this mod. I am able to hit full boost by 2300rpm (best case scenario in 4th gear). The old actuator definitely didn't have the balls to hold the gate shut and build boost as quickly as I wanted. After a while of running at wastegate pressure (which it could hold nicely to a 6500rpm redline producing a nice feeling pull), I decided to play around and see what I could do with it. My tune is still a work in progress, but I am currently running around 17psi. Unfortunately, I have had to turn adaptive knock control off because I was experiencing "ghost" knock all over the place. I would really like to turn it back on, but I'm worried about losing performance for no reason. Example of this "ghost" knock: In this picture, at part throttle, the ECU is pulling a lot of timing with no sign of knock from BITS or KRCOUNT. This is just one of a couple dozen accounts in this 30 minute log where the same thing was happening. After logging with adaptive knock turned off, there was no knock registered anywhere. I know some other people on the 4.4 thread were experiencing the same issue, but I didn't see a final fix anywhere. Did anyone sort this out or have any tips? While I am running in this configuration (adaptive off), will the ECU still react to real knock as indicated by KRCOUNT or BITS? Upcoming mods include the Forge CBV, a fix for the wastegate rod, and installing the tint that has been sitting under my bed since Christmas. Happy building/tuning/modding/fabbing! -Nick Edited April 6, 2016 by NB-V70R Quote Link to comment Share on other sites More sharing options...
Simply Volvo Posted April 8, 2016 Report Share Posted April 8, 2016 (edited) Here is what I did with my kinugawa wastegate. Made a spacer with nuts and washers. Then just install the bracket regularly. Edited April 8, 2016 by Simply Volvo 1 Quote Link to comment Share on other sites More sharing options...
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