bum2kev Posted May 22, 2012 Report Share Posted May 22, 2012 I wonder if that's why my exhaust cam was out of alignment after I used a similar tool... Factory spec Volvo tool is not flat on both of them. so those are correct. Quote Link to comment Share on other sites More sharing options...
Volvo5.0 Posted May 22, 2012 Report Share Posted May 22, 2012 Sucks Hussein. Hopefully you'll be able to salvage most of your investment. Looking at your logs when the clutch was slipping, it really doesn't look like the rev limiter even attempted to cut fuel. I'm sure most have felt it, but this is what the log looks like when fuel is cut.... I know with the big turbo, custom intake, and big cams the car probably feels sweet winding out to 8400rpm, and sounds amazing. My question, which could have been answered if the car had made it to the dyno at Carlisle is....Are you really making power all the way up to 8400rpm? Quote Link to comment Share on other sites More sharing options...
Dick Dastardly Posted May 22, 2012 Report Share Posted May 22, 2012 A slipping clutch under accel will not allow an over rev...MissIng a shift (from 4-3 instead of 4-5) will over rev and rev limiter will not stop the transmission from spinning the engine too fast..no matter what. Quote Link to comment Share on other sites More sharing options...
Captain Bondo Posted May 22, 2012 Report Share Posted May 22, 2012 A slipping clutch under accel will not allow an over rev...MissIng a shift (from 4-3 instead of 4-5) will over rev and rev limiter will not stop the transmission from spinning the engine too fast..no matter what. Absolutely. I don't think that's the scenario being claimed here, however. Quote Link to comment Share on other sites More sharing options...
Dick Dastardly Posted May 22, 2012 Report Share Posted May 22, 2012 Absolutely. I don't think that's the scenario being claimed here, however. I don't know I was saying for sure he missed a shift (while possible)...It was meant as an example of when a rev limiter doesn't "limit" revs..since there seems to be some confusion about rev limiters. Quote Link to comment Share on other sites More sharing options...
lookforjoe Posted May 23, 2012 Author Report Share Posted May 23, 2012 The issue is not that I don't see how fuel /ign rev limiting functions under normal load conditions, I've experienced that on numerous occasions. I still don't see how when all load is removed, there is any reason the revs wouldnt climb more than just a few hundred rpm regardless of whether the engine is still actually "running", given that I was WOT at the time & there is always delayed reaction time. Based on what you're saying, if I were to down shift into second from say 4th at WOT, the engine shoukd simply die; I doubt that is true. For all I know the logger is not accurate once the rev scale is passed; I also need to review the log to see how many fractions of a second it recorded over 9k rpm.. Edit: looks like about .3sec Edit: I did not miss any shifts. The clutch slipped twice immediately after 3-4th shifts on two occasions, I was not anywhere near redline when I shifted, around 6k I believe. The other slip occurred in a straight 4th gear pull in which I gradually increased throttle opening, and again, the clutch slipped around 6k . There is no way I'm hitting 600 ft/lb trq at 20 psi, with 700cc inj duty cycles in the 70%, it's not even close Edit: this will all make more sense once I've calmed down & the motor is torn apart for inspection. Right now I'm just too pissed off to really be thinking this through clearly. I would never have known the motor overevved to that extent if I had not been logging. No way to see the tach hang for .3 sec when all that's going through my mind at the time was FUCK!!!!!!!!!!!!! Quote Link to comment Share on other sites More sharing options...
Dick Dastardly Posted May 23, 2012 Report Share Posted May 23, 2012 (edited) If you shift from 4th to second the engine will not simply "die" but you will kill it! A rev limiter will not prevent the wheels/ transmission from driving the engine to high rpms in that situation. When you are accelerating you are injecting fuel and burning it with spark until a limit is reached and depending on ems you either cut fuel or spark. This will happen whether clutch is engaged or not...put car in neutral and floor it, it will bounce off the limiter at whatever rpm it is set at.. If you are going 100 mph in 3rd and ( under throttle or not) and throw a manual trans into second you will still be going 100mph only now it will be in 2nd not 3rd and the rpms will reflect that..in that case the turning of the wheels through the final drive and then the trans dictates how fast the crankshaft spins...Regardless of whether there is fuel or spark. A rev limiter is not a brake for your engine it simply stops adding fuel or spark under throttle. If you rev your engine in neutral to 6000 rpms and turn off the key...the rpms do not continue to climb. This is the same idea as a rev limiter. It "shuts it down" in a sense. Edited May 23, 2012 by scumcity14 2 1 Quote Link to comment Share on other sites More sharing options...
BlackT5 Posted May 23, 2012 Report Share Posted May 23, 2012 I can only imagine how pissed you must be. Try not to give it too much thought until you can assess the damage. Give it a few days, start taking it apart and hopefully most of it is salvageable.. Quote Link to comment Share on other sites More sharing options...
lookforjoe Posted May 23, 2012 Author Report Share Posted May 23, 2012 Factory spec Volvo tool is not flat on both of them. so those are correct. Are you sure? When I checked the Volvo tool, I though they were both horizontal (also squared off, not chamfered, of course)? I have to pick up parts from Volvo this afternoon - I'll look at both halves of the tool again... For VVT cam install, there is this diagram, where cams are positioned so that they rotate into place as cam cover is drawn down can't find anything on AllData that illustrates the cam slots, but I always assumed they were both supposed to be level for basic timing setup, not exhaust set early (retarded) several degrees Quote Link to comment Share on other sites More sharing options...
lookforjoe Posted May 23, 2012 Author Report Share Posted May 23, 2012 I'm wondering now whether I should look for a sprung disc - since I no longer have the DM, there is nothing to dampen the transfer of vibration to the trans - the rattle in 1st & 2nd is pretty horrible. Quote Link to comment Share on other sites More sharing options...
lookforjoe Posted May 23, 2012 Author Report Share Posted May 23, 2012 I know with the big turbo, custom intake, and big cams the car probably feels sweet winding out to 8400rpm, and sounds amazing. My question, which could have been answered if the car had made it to the dyno at Carlisle is....Are you really making power all the way up to 8400rpm? The dyno at Carlisle this year was Audi/VW dedicated, not a Dynojet like previous years, so I wouldn't have been able to dyno even if I had got there with the XR. I don't know at what point it levels off - I still want to do a dyno pull to 8000rpm once it's all resolved, just to see how much of a difference the modified intake really makes to upper end. For the time being, I will reset rev limit to 7600. I also have to take apart the Tial, it was supposed to be a 14psi setup, but clearly it goes to 20psi before fully opening. Quote Link to comment Share on other sites More sharing options...
550 Posted May 23, 2012 Report Share Posted May 23, 2012 Yeah, mine, even with the 7PSI spring shoots to 20PSI... and doesn't seem phased by that at all. Quote Link to comment Share on other sites More sharing options...
BlackT5 Posted May 23, 2012 Report Share Posted May 23, 2012 You set the boost control valve to 0 duty cycle and it still overshoots the wastegate spring pressure by that much?? I have the 10 psi spring and it barely creeps above that on a hard pull if set as I mentioned. As for the clutch, I was going to say that you could probably just use the sprung disc that comes in the 850 SO133F kit since it's probably the same thickness, but the input shaft on your trans is probably larger? I think it changed in 2002? That's not to say that they wouldn't have something suitable. Maybe try contacting Spec, but I would wait until you have the clutch out so you can determine what exactly went wrong. Quote Link to comment Share on other sites More sharing options...
blkaplan Posted May 23, 2012 Report Share Posted May 23, 2012 I wouldn't ever use a non sprung clutch disc on a street car with a standard style flywheel. Those springs help cut down vibration and make engagement and disengagement a bit smoother. Quote Link to comment Share on other sites More sharing options...
lookforjoe Posted May 23, 2012 Author Report Share Posted May 23, 2012 Cam tool comparison, shown based on orientation as per Volvo install diagram intake side - obvious that this will either advance the intake, or retard the exhaust, depending on which way you use the tool. exhaust side Volvo tool is level for all intents & purposes. Maybe you were referring to the 180º offset, Hanks? When I ordered the clutch, I went with the S60R setup - I should perhaps have specified sprung disc. Can't use the 850 disc it's both smaller OD & spline count is wrong. I have to send them pics when it's out, so when I have the conversation I'll see if they can swap for sprung, I'd rather not rattle my trans to pieces next.... Quote Link to comment Share on other sites More sharing options...
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