hughdogz Posted June 8, 2009 Share Posted June 8, 2009 Hi Guys, My compressor didn't come with a wastegate actuator signal port. Should I just tap one (the wall is kind of thin)? Do I need to weld a bung? Do I need two ports like the stock one that "y" together? Thanks! -hughdogz Quote Link to comment Share on other sites More sharing options...
md614 Posted June 8, 2009 Share Posted June 8, 2009 You could run a line to one of the intake manifold ports to your wastegate if you want too instead,or tape a line into the compressor. Quote Link to comment Share on other sites More sharing options...
RS Speed Posted June 8, 2009 Share Posted June 8, 2009 or you can add a niple to you intercooler piping close to your turbo so you have short vacuum lines and you dont have to mess with the turbo. Quote Link to comment Share on other sites More sharing options...
hughdogz Posted June 8, 2009 Author Share Posted June 8, 2009 You could run a line to one of the intake manifold ports to your wastegate if you want too instead,or tape a line into the compressor. I thought of this, but then you'd get all the pressure drop from the IC tubing and intercooler (perhaps a couple psi below compressor pressure). Plus, when the throttle body is closed between shifts, you're not getting the "surge pressure" before my recirculation valve opens (not that that should be an issue). or you can add a niple to you intercooler piping close to your turbo so you have short vacuum lines and you dont have to mess with the turbo. That's what I was thinking, and will probably go this route. I appreciate the feedback Guys! Quote Link to comment Share on other sites More sharing options...
Nigel Posted June 9, 2009 Share Posted June 9, 2009 Is something like this what you had in mind? http://www.atpturbo.com/Merchant2/merchant.mvc?Screen=PROD&Product_Code=ATP-FTG-010&Category_Code=ATP-FTG1 Nigel '73 240ZT Quote Link to comment Share on other sites More sharing options...
Tony D Posted June 9, 2009 Share Posted June 9, 2009 I thought of this, but then you'd get all the pressure drop from the IC tubing and intercooler (perhaps a couple psi below compressor pressure). Plus, when the throttle body is closed between shifts, you're not getting the "surge pressure" before my recirculation valve opens (not that that should be an issue) Maybe, but you can plumb that separately. Whe on-boost, there is a drop...but all that does is hold your wastegate closed tighter longer till manifold pressure builds to the pressure the wastegate is set to lift. In practical application, the boost comes on harder like this, and modulates pretty well on partial lift-throttle (at least in my experience.) What you DO get though is a VACUUM signal to your wastegate actuator which opens it WIDE AND QUICK slowing the turbo on lift-shift. Never thought about that one, didja? Mine is in the manifold plenum... Quote Link to comment Share on other sites More sharing options...
DeleriousZ Posted June 9, 2009 Share Posted June 9, 2009 Also, with the signal coming from the manifold, and you're not using a boost controller, you should be seeing wastegate spring pressure (say 8psi spring in the wastegate) in the intake manifold, rather than 1 or 2psi less due to pressure drop across the intake piping system/intercooler. Quote Link to comment Share on other sites More sharing options...
hughdogz Posted June 9, 2009 Author Share Posted June 9, 2009 Never thought about that one, didja? Mine is in the manifold plenum... All this is great information!! Many thanks Tony et al. Now I just have to purchase (or fabricate) a wastegate actuator bracket. I'm probably going to go with a Forge Motorsport actuator where you can swap out the preload spring. Quote Link to comment Share on other sites More sharing options...
Nigel Posted June 9, 2009 Share Posted June 9, 2009 Whe on-boost, there is a drop...but all that does is hold your wastegate closed tighter longer till manifold pressure builds to the pressure the wastegate is set to lift. In practical application, the boost comes on harder like this, and modulates pretty well on partial lift-throttle (at least in my experience.) I've dataloged the boost curve with the wastegate actuator source on the manifold and the turbo and there are obvious boost spikes with the source on the manifold because of the delay in the signal getting to the actuator. What you DO get though is a VACUUM signal to your wastegate actuator which opens it WIDE AND QUICK slowing the turbo on lift-shift. How does a vacuum signal OPEN the actuator? And why do you want to SLOW the turbo on lift-shifts? Something isn't adding up here... Nigel '73 240ZT Quote Link to comment Share on other sites More sharing options...
slown280z Posted June 9, 2009 Share Posted June 9, 2009 I've dataloged the boost curve with the wastegate actuator source on the manifold and the turbo and there are obvious boost spikes with the source on the manifold because of the delay in the signal getting to the actuator. How does a vacuum signal OPEN the actuator? And why do you want to SLOW the turbo on lift-shifts? Something isn't adding up here... Nigel '73 240ZT Are the spikes bad enough to warrant changing it to the turbo? Also, if you have an electronic boost controller, if the signal wire is on the manifold, it regulates the pressure that the engine is seeing, not the turbo. Also, I agree, wouldn't a vacuum source close the actuator? Quote Link to comment Share on other sites More sharing options...
Tony D Posted June 11, 2009 Share Posted June 11, 2009 I've dataloged the boost curve with the wastegate actuator source on the manifold and the turbo and there are obvious boost spikes with the source on the manifold because of the delay in the signal getting to the actuator. Quantify the spikes. A lof of that will depend on the type of plenum volume you have, flow of the compressor in an efficiency island, actuator type, and boost controller. Spikes are not detrimental unless they are uncontrolable or too large that the fueling system can not accomodate them. Yes, you will come on-boost harder, and MAY overshoot your set boost setting minimally. With a controller that controls based on rate-of-change in boost, this is easily controlled to be a non-issue. Most spikes are under 2psi, if that. How does a vacuum signal OPEN the actuator? And why do you want to SLOW the turbo on lift-shifts? The actuator generally works with spring pressure against pressure to OPEN. If you apply vacuum to a pressure side of the manifold it CLOSES (I just realized I may have mis-typed it, I meant to say vacuum CLOSES the actuator for better on-throttle response. Which I think is what you are getting at is a 'good thing' Nigel? Porting the turbo discharge will not do this, your wastegate stays open and you lazily come back on-boost. When you go to vacuum, that wastegate bypass closes TIGHT letting all energy go through the turbine, keeping lift-throttle turbine speeds up for rapid response. Coupled with a properly designed Compressor Bypass Valve, response can be quickened. Some electronic boost controllers will do similar things, dual ported actuators can also be used in this manner. Something isn't adding up here... I mistyped one word. Sorry, I'm 7000 miles from home, haven't been there for a month, and the idiots at Garuda called me at 2AM two nights running and have totally screwed my sleep schedule back up, so if I'm a little off, forgive me. It should have been obvious that vacuum would close the actuator, and do what I mentioned. I was concurrently thinking about the BOV slowing the turbo if it wasn't set right, and the thoughts crossed at somewheres around midnight... It's an hour earlier now, and I'm thinking better... Quote Link to comment Share on other sites More sharing options...
WizardBlack Posted June 16, 2009 Share Posted June 16, 2009 Listen to Tony. He has everything right. Many turbo installs use the manifold for boost reference to the turbo. Pressure drop can be several pounds or not much at all. Likewise for boost spikes, etc. You just have to try each way and see which one is agreeable to you. I use the manifold, myself. Quote Link to comment Share on other sites More sharing options...
WizardBlack Posted June 16, 2009 Share Posted June 16, 2009 Hi Guys, My compressor didn't come with a wastegate actuator signal port. Should I just tap one (the wall is kind of thin)? Do I need to weld a bung? Do I need two ports like the stock one that "y" together? Thanks! -hughdogz Just to the left of the 'A' in 'A/R' (with text right side up) is probably a pretty good spot to drill and tap for an 1/8" pipe thread fitting. If you want to go that way. They usually have plenty of meat to tap into. I've done it on plenty of turbos. You can reach in and check thickness easily enough. It doesn't take much to be fine in that kind of situation; maybe 1/8". Quote Link to comment Share on other sites More sharing options...
hughdogz Posted June 16, 2009 Author Share Posted June 16, 2009 ^^^ Cool! Thanks Guys, keep the conversation going...this is interesting stuff. Quote Link to comment Share on other sites More sharing options...
stony Posted June 16, 2009 Share Posted June 16, 2009 I usually put my pickup on the manifold. this will give you accurate boost pressure actually getting to the motor. this is also where most guys hook the boost gauges into Quote Link to comment Share on other sites More sharing options...
WizardBlack Posted June 17, 2009 Share Posted June 17, 2009 Bottom line is intercoolers cause some level of pressure drop. With this, you have the following options: Tap at turbo outlet ---> More careful, gradual spool, slightly less boost gets to the engine, wastegate keeps open a bit more on shift (if it was open when you shift) Tap at manifold ---> More aggressive spool, possible boost spike, more boost gets to the engine, vacuum can pull the wastegate shut more during shift which redirects more exhaust by the turbine wheel to keep it going Whichever way you do it, try to use silicone vacuum line (not cheapy vinyl junk from a parts store) or thick wall rubber as an acceptable secondary option. Likewise, use clamps or good wire ties to hold every single vacuum line in place. I use tie wraps and double them up. To know how far the tie wraps will go, I install one or two and tighten them until they break so I know how far I can go. Quote Link to comment Share on other sites More sharing options...
Nigel Posted June 18, 2009 Share Posted June 18, 2009 Bottom line is intercoolers cause some level of pressure drop.With this, you have the following options: Tap at turbo outlet ---> More careful, gradual spool, slightly less boost gets to the engine, wastegate keeps open a bit more on shift (if it was open when you shift) Tap at manifold ---> More aggressive spool, possible boost spike, more boost gets to the engine, vacuum can pull the wastegate shut more during shift which redirects more exhaust by the turbine wheel to keep it going I think that's a fair assessment if you're not using any kind of boost control other than a direct connection to the actuator. But if you're using a device that blocks the signal, like a solenoid or ball and spring controller then that will change things. Boost level and spool speed are no longer issues. My results were obtained with a Hallman controller (Ball and spring). Unfortunately, I don't have time to elaborate more, but I wanted to throw that in there... Nigel Quote Link to comment Share on other sites More sharing options...
hughdogz Posted June 19, 2009 Author Share Posted June 19, 2009 That's what I've been thinking too, Nigel. If I go with a one-way check-valve MBC (or PWM solenoid) I won't have the above options. Using a boost controller with the wastegate means there is no way to get vacuum to pull the actuator shut to have the boost come on harder. Mechanical versus electrical (analog versus digital) Quote Link to comment Share on other sites More sharing options...
slownrusty Posted June 19, 2009 Share Posted June 19, 2009 Sorry for the late chime in, Hugh, thought you were running an external wastegate? Did I miss something? Yasin Quote Link to comment Share on other sites More sharing options...
hughdogz Posted June 19, 2009 Author Share Posted June 19, 2009 Sorry for the late chime in, Hugh, thought you were running an external wastegate?Did I miss something? Yasin I haven't actually started my car yet, but I upgraded to a T3/T04E and I'm going to use the "Ultimate Internal Wastegate" from ATP turbos: Quote Link to comment Share on other sites More sharing options...
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