lookforjoe Posted January 26, 2011 Author Report Share Posted January 26, 2011 That duration if accurate makes the cam absolutely worthless. It's the same cam for all dual VVT turbos. Wizzard_Al quoted Vadis "According to VADIS, the exhaust is able to be varied by 30 degrees, while the intake can be varied by 50 degrees of CRANKSHAFT rotation." What bearing would that have on the cam duration? I don't know the theory here. I have no reason to doubt the ability of my speed shop to measure cam duration. I will ask him to clarify. Link to comment Share on other sites More sharing options...
magicaljake Posted January 26, 2011 Report Share Posted January 26, 2011 It's the same cam for all dual VVT turbos. including the s60r? Link to comment Share on other sites More sharing options...
NEU Posted January 26, 2011 Report Share Posted January 26, 2011 The dual VVT LPT cams are: 8670354 INT .315" lift 264º duration @ .006" That's much less lift than a older turbo intake cam! So are you going to keep this cam or look for a NA cam? I'm interested in finding out which version is better the -'02 or the '03+ So are you going to keep this cam or look for a NA cam? I'm interested in finding out which version is better the -'02 or the '03+ Opps just saw your wanted NA cam post... Link to comment Share on other sites More sharing options...
lookforjoe Posted January 26, 2011 Author Report Share Posted January 26, 2011 including the s60r? Correct. ALL Dual VVT Turbos use that exhaust cam. So are you going to keep this cam or look for a NA cam? I'm interested in finding out which version is better the -'02 or the '03+ Opps just saw your wanted NA cam post... Yeah. I'll use what I have if it comes down to that, but clearly the R or NA intake cam would (presumably) be better. Link to comment Share on other sites More sharing options...
lookforjoe Posted January 26, 2011 Author Report Share Posted January 26, 2011 It's the same cam for all dual VVT turbos. Wizzard_Al quoted Vadis "According to VADIS, the exhaust is able to be varied by 30 degrees, while the intake can be varied by 50 degrees of CRANKSHAFT rotation." What bearing would that have on the cam duration? I don't know the theory here. I have no reason to doubt the ability of my speed shop to measure cam duration. I will ask him to clarify. Spoke with the machinist. At most, he said he could be off by 2%, if that. Greater duration would allow for what? More complete evacuation of the chamber? How does that relate to the intake lift & duration, when the VVT variables are factored in? I have no clue as to that... Link to comment Share on other sites More sharing options...
Captain Bondo Posted January 27, 2011 Report Share Posted January 27, 2011 Not doubting you, but can you explain how? I must be overlooking something obvious, I don't see how an increased runner length would improve this. Scavenging works on turbo motors too if you do it right. The pulses are not completely absorbed by the turbine, they are reflected back as negative waves that can be uses to scavenge exhaust gases from subsequent combustion events. The longer the runner, the lower the resonant frequency and thus the lower the rpm at which this happens most effectively. If you improve low rpm breathing you improve spool. It's really that simple. Hussein, 50 crankshaft degrees means 25 cam degrees. The crank rotates at 2x camshaft speed so they're just clarifying. And yeah I'd like to make a 5 cyl header some day but we'll probably all drive flying cars by then. :lol: Link to comment Share on other sites More sharing options...
wizzard_al Posted January 28, 2011 Report Share Posted January 28, 2011 Wizzard_Al quoted Vadis "According to VADIS, the exhaust is able to be varied by 30 degrees, while the intake can be varied by 50 degrees of CRANKSHAFT rotation." What bearing would that have on the cam duration? I don't know the theory here. I have no reason to doubt the ability of my speed shop to measure cam duration. I will ask him to clarify. Hussein: The VVT has nothing to do with duration, that is determined by the individual cam lobe. The VVT simply changes the relationship between the intake and exhaust cams, determining where the maximum torque is, maximum horsepower is, etc. The difference between the intake and exhaust cam lobes is know as LSA (Lobe Separation Angle) Basically, small LSA is better for low rpm performance, and idle, while large LSA angle is better for more high end power. Volvo uses VVT more for emissions control, so that the exhaust cam, for instance on my '01 T5, is setup up to let the car have a faster warm up, fire up the cat converter sooner, and thus reduce emissions. Most American engines have never been able to vary LSA until recently. Viper has a unique cam on the v10 that allows intake and exhaust lobes to be varied, even though it is a single cam. Ford twin cam engines have VVT, and it gives them a major boost in performance, while keeping emissions under control. They can set up cam LSA to be optimum for low speed, as well as for emissions, yet vary the cams so that the LSA is optimum for mid and high end performance. Europeans and Japanese have been ahead in this area mostly because they have multiple cam engines. For instance, BMW VANOS is a VVT system, Toyota has it, etc. I've used this following quote before in another post. It comes from Crane Cams: "Lobe separation is the distance (in camshaft degrees) that the intake and exhaust lobe centerlines (for a given cylinder) are spread apart. Lobe separation is a physical characteristic of the camshaft and cannot be changed without regrinding the lobes. [NOTE: presumes a single cam, not dual camshaft] This separation determines where peak torque will occur within the engine's power range. Tight lobe separations (such as 106?) cause the peak torque to build early in basic RPM range of the cam. The torque will be concentrated, build quickly and peak out. Broader lobe separations (such as 112?) allow the torque to be spread over a broader portion of the basic RPM range and shows better power through the upper RPM." So you can see that changing the LSA can impact an engine so that it can have the best of both worlds. Notice that Crane talks about a difference of 6 degrees, yet we are talking about 20 or 30 degrees, so imagine what that can do for you. Here is Crane's comments about advancing or retarding a cam. Remember, this is for a single cam engine. 'Advancing the cam will shift the basic RPM range downward. Four degrees of advance (from the original position) will cause the power range to start approximately 200 RPM sooner. Retarding it this same amount will move the power upward approximately 200 RPM. This can be helpful for tuning the power range to match your situation. If the correct cam has been selected for a particular application, installing it in the normal "straight up" position (per the opening and closing events at .050" lifter rise on the spec card) is the best starting point." Remember, .050" is 1.27 mm. Also remember our white engine is an interference engine, so you have only so much advance or retard that is possible on this engine before you start to have pistons kissing valves. Obviously, with the VVT, Volvo has told us there is more than 10 degrees of possible advance or retard with certain cams. Probably why the lift is not as high as the early NA engines, they had fixed relationship to the crank, i.e., no VVT. My guess is that the VVT engines are about maxed out on lift because of the use of the VVT. If you disabled VVT, you'd be able to go for more lift. Crane's discussion of duration: "Duration is the period of time, measured in degrees of crankshaft rotation, that a valve is open. Duration (at .050" lifter rise) is the deciding factor to what the engine's basic RPM range will be. Lower duration cams produce the power in the lower RPM range. Larger duration cams operate at higher RPM, but you will lose bottom end power to gain top end power as the duration is increased. (For each ten degree change in the duration at .050", the power band moves up or down in RPM range by approximately 500 RPM.)" Finally, interesting comment about measuring duration: "In order for duration to have any merit as a measurement for comparing camshaft size, the method for determining the duration must be the same. There are two key components for measuring duration-- the degrees of crankshaft rotation and at what point of lifter rise the measurements were taken. Advertised durations are not taken at any consistent point of lifter rise, so these numbers can vary greatly. For this reason, advertised duration figures are not good for comparing cams. Duration values expressed at .050" lifter rise state the exact point the measurement was taken. These are the only duration figures that are consistent and can accurately be used to compare camshafts." Thus, most american cam manufacturers of any reputation use duration at .050' lift. More information from Crane Cams at this page: http://www.cranecams.com/faqlist.php?x_catagory=1 Link to comment Share on other sites More sharing options...
lookforjoe Posted January 31, 2011 Author Report Share Posted January 31, 2011 Correct. ALL Dual VVT Turbos use that exhaust cam. Yeah. I'll use what I have if it comes down to that, but clearly the R or NA intake cam would (presumably) be better. Found an '05 dual VVT NA intake cam ( B5244S6 / #8670147) made an offer of $35 - he accepted It's worth a shot -I'll have to get the valve rechecked/readjusted if the cam turns out to have a better lift. Link to comment Share on other sites More sharing options...
lookforjoe Posted January 31, 2011 Author Report Share Posted January 31, 2011 Scavenging works on turbo motors too if you do it right. The pulses are not completely absorbed by the turbine, they are reflected back as negative waves that can be uses to scavenge exhaust gases from subsequent combustion events. The longer the runner, the lower the resonant frequency and thus the lower the rpm at which this happens most effectively. If you improve low rpm breathing you improve spool. It's really that simple. Hussein, 50 crankshaft degrees means 25 cam degrees. The crank rotates at 2x camshaft speed so they're just clarifying. And yeah I'd like to make a 5 cyl header some day but we'll probably all drive flying cars by then. Kenny, with all your testing with the 960 cams, I'm curious as to what relative timing you have found beneficial - I saw in Project 755's thread where you commented on this, when discussing deleting the VVT... Link to comment Share on other sites More sharing options...
Captain Bondo Posted February 1, 2011 Report Share Posted February 1, 2011 I ended up around 1 degree advanced on the exhaust cam and 3 degrees retarded on the intake cam. Totally different cams and a relatively big turbo though so I doubt your settings will be similar. What I did find though is I could not tune them on the street. I tend to think my "ALL GLORY TO THE HYPNOTOAD dyno" is good, but I was way off when i actually tested it on a dyno. I had everything far too advanced, which suprised me. Link to comment Share on other sites More sharing options...
lookforjoe Posted February 1, 2011 Author Report Share Posted February 1, 2011 I ended up around 1 degree advanced on the exhaust cam and 3 degrees retarded on the intake cam. Totally different cams and a relatively big turbo though so I doubt your settings will be similar. What I did find though is I could not tune them on the street. I tend to think my "ALL GLORY TO THE HYPNOTOAD dyno" is good, but I was way off when i actually tested it on a dyno. I had everything far too advanced, which suprised me. Thanks for the input. I agree that street tuning is impractical, subtle changes in power band cannot really be discerned. What I have focused on is the part throttle/low end 'feel'. I will be going back to dyno my current setup soon- after getting IPD's cam tool & finding my exhaust timing was way off where I thought it was, I settled on EXH 2º Adv & INT 2º Retard. They were at EXH 2º Retard & INT 0º, which made initial low rpm accel rather flat. EGT's have gone up slightly in the 4th gear 6-7K WOT range - I'm at 1300ºF if I shift @ 7K ( I don't normally, but I wanted to see what they were climbing to. Link to comment Share on other sites More sharing options...
s60wot Posted January 12, 2012 Report Share Posted January 12, 2012 So, after reading all of this I think I have 2 choices: 1. Use my current 01 T5 head and cams (port, polish, 3 angle) 2. Use the 02 head I bought with my 01 T5 cams (port, polish, 3 angle) Now, where do i get it done right? Has anyone used a machine shop with a CNC file to do these newer heads? Anyone use ever use http://www.r-sportinternational.com/index.php for head work on a newer style head for P2 car? Link to comment Share on other sites More sharing options...
BlackT5 Posted January 12, 2012 Report Share Posted January 12, 2012 There must be a bunch of shops in FL to choose from? Doesn't have to specialize in Volvo to do a good job. Link to comment Share on other sites More sharing options...
s60wot Posted January 12, 2012 Report Share Posted January 12, 2012 True if you want hand porting. I was looking for CNC machine job by someone that has done a newer T5 head. It's also nice to get a reco from someone that has had it done rather than just take it somewhere and hope for the best. I took a turbo to a local machine shop to have a hole plugged and another one opened up and threaded. He charged me $90 for about a $40 job and the hole was too shallow for the banjo bolt so I ended up grinding the bolt shorter rather than take it back and wait for him to fix it. Link to comment Share on other sites More sharing options...
Piston Slapper Posted January 12, 2012 Report Share Posted January 12, 2012 NA VVT cars had VVT on the intake cam instead of the exhaust cam. I would like to note that as far as I can find out NAs did not get VVT on the intake cam until 2000. My '99 has the newer head style but no VVT. Which makes me wonder if the cams in a '99 NA would be useful to a build, but I'm not about to tear my head apart to check the journals. Maybe worth someone else looking into, hope I've helped a little. Link to comment Share on other sites More sharing options...
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