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Discussion Starter · #1 ·
hey javad, can the gpo's on the 034 control vvt? my dad and i were looking at a 5.0 DOHC benz engine with the valve cover that we were working on and noticed the intake cam has a controller for it. i don't know the detalis on how it works, if it just goes off a voltage reading or what.

would you have any ideas about this? my dad would like to transplant one of these motors into an older body and turbo it, and of course i keep preachin' 034 to him, so he wants to do it now.

later,D 00 D :D
 

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If it's a simple selondoid like I think most of those cam 'switches' are then yeah you should be able to get the GPO's to control it all you want. Similarly you can do the same with something like the later audi V8 intake manifolds that had the variable runner length setup, just use the gpo to trigger it off and you can setup when and where you want the added oomph.

good stuff :)
 

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That's right, what Nate said. Some systems may use all kinds of proprietary techniques, but on the cam timing systems that use a pulsed voltage signal or a simple solenoid actuation, then yes, on of the GPO's will do it no problem.
 

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I dont know that much about European cars so i really cant answer for them but japanese cars i am sure i can help.if Javad Incorporates Variable Valve Timing into his system then you cna use a VVti Controller but you have to be careful with this system as the oil pressure in the bottom half of the engine could become very low and we all know what happens then.
On the starlet i built up , i removed the Cam Angle Sensor just because i think VVT is not that great of an addition.Do not know how you guys think about it but i know the car performs slightly better now with the MSD attached.
 

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Discussion Starter · #5 ·
well, the particular motor I am talking about is not available any other way as far as i know, so i wouldn't know how it performs without it. and i'm not sure about the oil pressure deal, but i'm prety sure that this mercedes setup is purely electronic.
 

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Ya, just see if you can find out what the control is, its likely using oil pressure to actuate the cam tensioner to rotate the cam to a different centerpoint. Its likely controlled with an electronic solenoid like most systems, in which case no problem.
 

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so it would work easily with the 2.8l 24v vr6 oil pressure control ed, by two solenoids with a PWM signal, one for the intake cam the other for exhaust cam right or should i just only use the intake cam :tard: and can i map for both solenoids?
 

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You should be able to map for both selonoids just fine, you'll just have to use 2 GPOs. 8)
 

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augh use a whole 2,.. gaugh,. lol
so it will work,. but the gpos will never be able to have feedback from the cam sensors,. so geting it to work would be a trial and eror right, cause i would never know wut the advance of the cam is,. so should I program this gpo on a dyno,. or are there easyer ways
 

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You can do it stationary with the engine idling if you want (I'd imagine, as long as the oil pressure is sufficient at idle). Just tie the GPO to the TPS sensor (with the sensor off the throttle :p), adjust the values in the mapping to see what corelates to your cam movement while twisting the TPS sensor to move through the map, then you'll know exactly what values you need to move the cam x%

Finding the 'money' points to start moving the cams is where the dyno will come in 8)
 

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You have to be careful to check how the cam control works. Some systems use constant pressure that works against a return spring. This will work well with 034 and an open loop control with defined duty cycles. Other systems use two valves and put pressure on either side of a diaphragm to allow for quicker movement in either direction. With that type of setup without a return spring if you give a pwm if will just keep moving the cam until it hits a stop.

I definitely recommend taking stuff apart and understanding how it works. With the open loop control of 034 you must insure that there will be some kind of reactive force (return spring or rotational direction of cam are examples) as you apply oil pressure.

Or convince 034 and company to put in closed loop cam control using the cam sensor.
 
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