barneybrendan Posted September 8, 2011 Author Share Posted September 8, 2011 come on noz .hopefully that is the problem ,but its definately not going to help matters if the airflow isnt sufficiant enough.Just a case of fix that and see what happens. Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted September 8, 2011 Share Posted September 8, 2011 When you open the throttle and close it again the revs don't immediately drop, it hangs on for a second, then they drop. That doesn't seem right. Quote Link to comment Share on other sites More sharing options...
barneybrendan Posted September 8, 2011 Author Share Posted September 8, 2011 When you open the throttle and close it again the revs don't immediately drop, it hangs on for a second, then they drop. That doesn't seem right. it did that before then it went away once AFR mapped it.Im open to sugestions on reasons why it would be like that Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted September 8, 2011 Share Posted September 8, 2011 I have never really understood why it's collapsing hoses on the suction side, and suspect it's somehow sucking the throttle plate open after it's revved up. I thought these things had a bypass system to send air around, rather than through the SC except when a load is placed on the engine? To be honest I still haven't got my head around the plumbing on this install, can you draw a diagram of how it's all strung together, and scan and post it? Quote Link to comment Share on other sites More sharing options...
Shane Posted September 8, 2011 Share Posted September 8, 2011 (edited) I have never really understood why it's collapsing hoses on the suction side, and suspect it's somehow sucking the throttle plate open after it's revved up. I thought these things had a bypass system to send air around, rather than through the SC except when a load is placed on the engine? To be honest I still haven't got my head around the plumbing on this install, can you draw a diagram of how it's all strung together, and scan and post it? I am not in any way going to be pretend to be an expert on this stuff but spent a lot of time and effort on my attempt and your description Chris is exactly how mine was configured. I had a vacum activated valve that was normally open on idle and allowed air to bypass the charger. As soon as the vacum increased the valve closed and everything came through the charger.....then the shaft broke. Edited September 8, 2011 by Shane Added photo (see edit history) Quote Link to comment Share on other sites More sharing options...
barneybrendan Posted September 8, 2011 Author Share Posted September 8, 2011 (edited) this is a basic drawing the bypass valve is open at idle and closes once the throttle is opend this is to let boosted air circulate ,basicly in through the charger out the bypass valve and back through the charger again.This is why i needed it mapped so it gave extra fuel for that time the throttle was opend as the air in the system waiting is getting hotter as it circulates.It Edited September 8, 2011 by barneybrendan (see edit history) Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted September 8, 2011 Share Posted September 8, 2011 Are you sure the bypass valve is opening, and the hoses to it are of adequate bore? Can you indicate on the drawing which hoses were trying to collapse? What happens if you jam the bypass valve open and rev it up? Does it still fail to drop the revs quickly? Quote Link to comment Share on other sites More sharing options...
barneybrendan Posted September 8, 2011 Author Share Posted September 8, 2011 (edited) Are you sure the bypass valve is opening, and the hoses to it are of adequate bore? Can you indicate on the drawing which hoses were trying to collapse? What happens if you jam the bypass valve open and rev it up? Does it still fail to drop the revs quickly? the bypass valve is opening as you can see the rod pushing into the actuator as it sucked open.When i rev it the bypass valve closes and opens again when i let it off.I will double check that its not catching on anything.The hose that is collapsing now is the first 90 degree bend after the throttle body.It did actually jam open when i first started it as it caught on the jubilee clip ,it still failed to drop instantly. Edited September 8, 2011 by barneybrendan (see edit history) Quote Link to comment Share on other sites More sharing options...
David P Posted September 8, 2011 Share Posted September 8, 2011 (edited) The pipe to the ICV needs to be connected in between butterfly and air filter and I'm not sure it can seal against the positive pressure, especially if is an N/A ICV, it would be better on the suck side. Edited September 8, 2011 by David P (see edit history) Quote Link to comment Share on other sites More sharing options...
barneybrendan Posted September 8, 2011 Author Share Posted September 8, 2011 The pipe to the ICV needs to be connected in between butterfly and air filter. it is mate ,its the v8 throttlebody and im using the same pipe from the bottom of it as you. Quote Link to comment Share on other sites More sharing options...
David P Posted September 8, 2011 Share Posted September 8, 2011 Just added some more, not sure the N/A ICV will be happy with positive pressure, a T.T. one fits the same, but is a lot stronger. Quote Link to comment Share on other sites More sharing options...
barneybrendan Posted September 8, 2011 Author Share Posted September 8, 2011 (edited) Just added some more, not sure the N/A ICV will be happy with positive pressure, a T.T. one fits the same, but is a lot stronger. ok so fitting the icv in the itake pipe somewhere wont be a problem and could get a mk3 turbo one easily enough.I will give that a try then.I pressume if the icv isnt closing right away there will be an extra amount of air to be taken in thus causing the delay in the idle dropping Edited September 8, 2011 by barneybrendan (see edit history) Quote Link to comment Share on other sites More sharing options...
David P Posted September 8, 2011 Share Posted September 8, 2011 (edited) Just added some more to previous post, not sure the N/A ICV will be happy with positive pressure, a T.T. one fits the same, but is a lot stronger. Edited September 8, 2011 by David P (see edit history) Quote Link to comment Share on other sites More sharing options...
barneybrendan Posted September 8, 2011 Author Share Posted September 8, 2011 Just added some more, not sure the N/A ICV will be happy with positive pressure, a T.T. one fits the same, but is a lot stronger. [ATTACH=CONFIG]138660[/ATTACH] so will the tt one fit where the na one is.If so that will be the easiest thing to try for now. Quote Link to comment Share on other sites More sharing options...
Scott Posted September 8, 2011 Share Posted September 8, 2011 only read it quickly. whoooops!! edit: saying some pretty stupid things lately. need to lay off the ginger beer Don't be silly, ginger beer is awesome Quote Link to comment Share on other sites More sharing options...
David P Posted September 8, 2011 Share Posted September 8, 2011 Simple fix would be a straight swap for a JZA80 TT ICV. If you want a Mk3 TT ICV, I have one, but would like the £20 I paid for it for it. Quote Link to comment Share on other sites More sharing options...
barneybrendan Posted September 8, 2011 Author Share Posted September 8, 2011 cheers Quote Link to comment Share on other sites More sharing options...
David P Posted September 8, 2011 Share Posted September 8, 2011 so will the tt one fit where the na one is.If so that will be the easiest thing to try for now. Straight swap. Quote Link to comment Share on other sites More sharing options...
barneybrendan Posted September 14, 2011 Author Share Posted September 14, 2011 (edited) Simple fix would be a straight swap for a JZA80 TT ICV. If you want a Mk3 TT ICV, I have one, but would like the £20 I paid for it for it. [ATTACH=CONFIG]138662[/ATTACH] does the na connector fit that and are the wires the smae way.Also do you fancy being nice and send it to me with a flange and bit of pipe ready to weld on.MATE Edited September 14, 2011 by barneybrendan (see edit history) Quote Link to comment Share on other sites More sharing options...
David P Posted September 14, 2011 Share Posted September 14, 2011 If you can find one, the simplest way would be to use a Mk 4 TT ICV, straight swap and loom is plug and play. The Mk 3 ICV is the same strength as the Mk 4 version, is plug and play to the loom and is on a flange that would maybe fit onto TT inlet manifold position. I paid £20 plus P&P for this, if it's any use to you you can have it for £20 inc P&P. Here's some more snaps of it. Quote Link to comment Share on other sites More sharing options...
barneybrendan Posted September 15, 2011 Author Share Posted September 15, 2011 i might aswell have it and try mate.Give me a couple days Quote Link to comment Share on other sites More sharing options...
barneybrendan Posted September 15, 2011 Author Share Posted September 15, 2011 (edited) i fitted a reinforced pipe today for the intake as a tempory thing and had the bypass valve vacum off its on pipes rather than taking a feed from the old na throttbody.It started up fine but was ticking over at 3000rpm.Not really sure what is going on here. I have just been reading a write up about relieving supercharger pressure and it seems my problems are not just mine alone.It may seem that i am not actually relieving enough ir through the bypass valve.Option would be to fit a second smaller valve like the guy in the link did. http://home.windstream.net/mcfly/bypass_valves.htm I am going to put the na throttle body back on tomorrow and see what happens. Edited September 15, 2011 by barneybrendan (see edit history) Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted September 15, 2011 Share Posted September 15, 2011 I'd have thought you would need enough bypass air volume (in the bypass pipe and control valve), to feed the engine as if there was no SC there, so about 2.5 inches in internal diameter so as to cause no pressure drop? Probably controlled by the ecu rather than a simple vac source? How do Mercedes do it on the SL55 AMG? Quote Link to comment Share on other sites More sharing options...
David P Posted September 15, 2011 Share Posted September 15, 2011 (edited) i fitted a reinforced pipe today for the intake as a tempory thing and had the bypass valve vacum off its on pipes rather than taking a feed from the old na throttbody.It started up fine but was ticking over at 3000rpm.Not really sure what is going on here. I have just been reading a write up about relieving supercharger pressure and it seems my problems are not just mine alone.It may seem that i am not actually relieving enough ir through the bypass valve.Option would be to fit a second smaller valve like the guy in the link did. http://home.windstream.net/mcfly/bypass_valves.htm I am going to put the na throttle body back on tomorrow and see what happens. That set up looks to be t.b. after charger, your t.b. butterfly is now before the charger and the only air that should pass when it's closed is through the ICV. At low rpm this air cannot be compressed by the charger because the bypass (recirculation) valve will be held open by the engine manifold vacuum. At tick-over the engine should behave as if normally aspirated. Edited September 15, 2011 by David P (see edit history) Quote Link to comment Share on other sites More sharing options...
barneybrendan Posted September 16, 2011 Author Share Posted September 16, 2011 the merc has an electronic valve which is prone to leaking and no good if you want to increase the boost.Looking on the merc forums it seems it is removed and a vacum operated one fitted. My head is a bit fried ,the car was running fine on the dyno with the old setup.the only real difference is the v8 throttle body before the charger and the smaller pulley.With the small pulley obviously my boost has increased and the charger will be spinning faster on tickover,but would that increase the airflow past the bypass valve.What other reason would there be for the tickover to be so high. Quote Link to comment Share on other sites More sharing options...
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