BlackT5 Posted January 24, 2011 Report Share Posted January 24, 2011 I'll have the cam lift & duration #'s Monday - the shop is finishing up the head work. He called & gave me the lift (@ .006") over the phone - but I didn't have a pen handy. 300º duration on the exhaust, but now I can't be sure he was surprised at how much more lift the exhaust cam has than the intake. This is what I've been working on the last day or so... Building the plenum to clear the PS, etc... is going to be a PITA. shooting for 210CID (1.5x displacement) Now you just need a nice exhaust manifold. ;) Link to comment Share on other sites More sharing options...
SomeGuy854 Posted January 25, 2011 Report Share Posted January 25, 2011 Outside of what Lucky has said, has anyone had success using an '03 LPT head on a 2.3L with the stock cams and got VVT working using either a custom setup or a dedicated VVT control module? I know some people have used the '03 head, deleted the VVT, and used '97 NA cams after having the appropriate head work done to account for the differences. Link to comment Share on other sites More sharing options...
Wagoneer855 Posted January 25, 2011 Report Share Posted January 25, 2011 Why do you want the VVT? Just for the fuel economy? It's been proven again and again that it gives absolutely no performance gains. Link to comment Share on other sites More sharing options...
ozzimark Posted January 25, 2011 Report Share Posted January 25, 2011 It's been proven again and again that it gives absolutely no performance gains. That may be true for peak power with the way the stock ECU manages the cam timing. Have any tests been done to show how it affects partial throttle, or has anyone tried to make up their own VVT maps? There is no way that moving the cam around to optimize the timing for a given rpm & load won't give more power across the rpm range than just a static setup. Link to comment Share on other sites More sharing options...
lookforjoe Posted January 25, 2011 Author Report Share Posted January 25, 2011 That may be true for peak power with the way the stock ECU manages the cam timing. Have any tests been done to show how it affects partial throttle, or has anyone tried to make up their own VVT maps? There is no way that moving the cam around to optimize the timing for a given rpm & load won't give more power across the rpm range than just a static setup. Did you see the duration on the exhaust cam? The lift on the intake is as low as the early T3 cams - I'm of two minds as to whether I should look for an R or NA intake cam, and get the valves adjusted again - without the specs on them, it's hard to say. Link to comment Share on other sites More sharing options...
Fishey Posted January 25, 2011 Report Share Posted January 25, 2011 That duration if accurate makes the cam absolutely worthless. Link to comment Share on other sites More sharing options...
ozzimark Posted January 25, 2011 Report Share Posted January 25, 2011 What's your intake cam PN? I agree with Fishey. That duration is totally nuts. No offense, but I'd seriously question your machine shop guy.. I measure 0.331" lift on my non-VVT intake cam (6900044), which is damned close to the specified lift by Volvo, 8.40mm. Your 0.315" is 8.00mm, which is a bit more than the old intake cams that had 7.90mm advertised. NA Intake cam: 250º, 8.45 mm Exhaust cam: 252.6º, 8.45 mm Turbo Intake cam: 242º, 7.90 mm Exhaust cam: 243.5º, 7.90 mm Link to comment Share on other sites More sharing options...
Volvo5.0 Posted January 25, 2011 Report Share Posted January 25, 2011 I measure 0.331" lift on my non-VVT intake cam (6900044), which is damned close to the specified lift by Volvo, 8.40mm. Yeah, that's what I got on the 2000xc intake cam. PN on that cam is 9207942. Link to comment Share on other sites More sharing options...
lookforjoe Posted January 25, 2011 Author Report Share Posted January 25, 2011 Now you just need a nice exhaust manifold. Something like a 5cyl version of this would be nice Link to comment Share on other sites More sharing options...
ozzimark Posted January 25, 2011 Report Share Posted January 25, 2011 Those runners are way too long and have some scary looking bends These are pretty long too, but at least they have the correct number of runners and smoother transitions Link to comment Share on other sites More sharing options...
Captain Bondo Posted January 25, 2011 Report Share Posted January 25, 2011 Those runners are way too long and have some scary looking bends These are pretty long too, but at least they have the correct number of runners and smoother transitions Way too long? Based on what, dare I ask? :monkey: Link to comment Share on other sites More sharing options...
ozzimark Posted January 26, 2011 Report Share Posted January 26, 2011 Personal feeling. I don't have empirical evidence to back it up, but it seems that for the best turbo response, the manifold should be as short as possible, within reason and without compromising the smoothness of the flow path. That keeps the heat loss out the manifold walls down, the volume to be pressurized down, and keeps pulse energy up. That manifold had both some tighter bends and longer runners than I typically see on a turbo manifold. We don't have the space required to make a "header" design that is effective for proper evacuation (like you would see on an all-motor build), so trying will only be counter-productive since you'll be taking away from what should make the turbo respond quickly. That said, I'm sure it's still better than a design like the "R" manifold we love around here so much :lol: Link to comment Share on other sites More sharing options...
Captain Bondo Posted January 26, 2011 Report Share Posted January 26, 2011 Personal feeling. I don't have empirical evidence to back it up, but it seems that for the best turbo response, the manifold should be as short as possible, within reason and without compromising the smoothness of the flow path. That keeps the heat loss out the manifold walls down, the volume to be pressurized down, and keeps pulse energy up. That manifold had both some tighter bends and longer runners than I typically see on a turbo manifold. We don't have the space required to make a "header" design that is effective for proper evacuation (like you would see on an all-motor build), so trying will only be counter-productive since you'll be taking away from what should make the turbo respond quickly. That said, I'm sure it's still better than a design like the "R" manifold we love around here so much FWIW, an important consideration you are missing is that more runner length improves the utilization of exhaust pulse energy at low engine speeds. The additional volume or heat loss from a few inches of runner length is insignificant when compared to this, along with improved design flexibility in terms of bend radius and merge angle generally afforded by longer runner lengths. If you're worried about heat loss, ceramic coat/header wrap, then any losses from a few inches of runner length are definitely irrelevant. The whole "you want a log header/short header for response" theory is a classic "tuning" wives tale. I swapped a stock cast manifold/Garrett 60 trim with 0.48 exhaust for one of my headers, with 17" long primaries and a 60 trim with 0.63 hot side, and it spooled faster. Link to comment Share on other sites More sharing options...
lookforjoe Posted January 26, 2011 Author Report Share Posted January 26, 2011 I swapped a stock cast manifold/Garrett 60 trim with 0.48 exhaust for one of my headers, with 17" long primaries and a 60 trim with 0.63 hot side, and it spooled faster. Shame you're not making 5 cyl versions! :D Link to comment Share on other sites More sharing options...
ozzimark Posted January 26, 2011 Report Share Posted January 26, 2011 FWIW, an important consideration you are missing is that more runner length improves the utilization of exhaust pulse energy at low engine speeds. 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. :sheep: Link to comment Share on other sites More sharing options...
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