Forced induction and auxilary port/VDI system...
Mountain Rotary Mod
Joined: Nov 2003
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From: Freaking Poland!!
Originally Posted by SonicRaT
I have. 
Alright, here's what I did. (Each run had the MBC at 12psi)
I used two servos, with with obvious custom brackets/etc to mount them back and away from the turbo and obviously space. I then did basically 3 gtech runs in with each config (yes, not quite dyno, but it's 4 hours away and I'm broke, so, STFU, don't want to hear it). Anyway, the net result was basically this, with them servo actuated the turbo began spooling about 200rpm earlier (this was just noticed) As for time comparison? The difference of both averages was less than .02, so I really don't think performance wise there's much else to say. Sorry, no VDI experience.
Overall result? I wasted my time. With the stock turbo and n/a rotors, you really won't have much to worry about, except keeping the tires planted.
Oh, previos poster was right, the S4 manifold flows better than the S5's.
Alright, here's what I did. (Each run had the MBC at 12psi)
I used two servos, with with obvious custom brackets/etc to mount them back and away from the turbo and obviously space. I then did basically 3 gtech runs in with each config (yes, not quite dyno, but it's 4 hours away and I'm broke, so, STFU, don't want to hear it). Anyway, the net result was basically this, with them servo actuated the turbo began spooling about 200rpm earlier (this was just noticed) As for time comparison? The difference of both averages was less than .02, so I really don't think performance wise there's much else to say. Sorry, no VDI experience.
Overall result? I wasted my time. With the stock turbo and n/a rotors, you really won't have much to worry about, except keeping the tires planted.
Oh, previos poster was right, the S4 manifold flows better than the S5's.
Joined: Dec 2001
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From: NY, MA, MI, OR, TX, and now LA or AZ!
Originally Posted by Parastie
Strange that the early spooling didn't help any, but of course this 200RPM isn't much. Do you think if you could change when they opened it would help?
Mountain Rotary Mod
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From: Freaking Poland!!
Originally Posted by SonicRaT
I didn't play too much with it, but having them open once the turbo spools might help a bit, since I was still having them open relatlively late (~3k rpm), that's something I didn't even think of trying.
Thread Starter
Joined: Nov 2002
Posts: 12,752
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From: Laredo, Tx
I think electronic actuation would be perfect for space restrictions but have a pressure switch to activate them not an RPM switch or whatever else. Say a switch activated by a certain PSI so that once it "see's" the turbo spooling the actuators kick over the sleeves and allow more flow.
Santiago
ps- thanks sonic for your input.
Santiago
ps- thanks sonic for your input.
Rotary Enthusiast
Joined: Jan 2003
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From: fl
why are you so set on pure electric activation? the turbo is giving you free presure to open the acuators.........(they only need like 3 psi wich you should have by 2-3kprms anyway) aaron cake's sugestion seems ideal if clearance is going to bee an issue and you can do it a X pressure using a simple bleed valve instead of an electric pressure sensor.
id be surprised if the stock actuators even hold up sitting right over a turbo. no way any plastic/electric compoents willl survive there.
id be surprised if the stock actuators even hold up sitting right over a turbo. no way any plastic/electric compoents willl survive there.
Mountain Rotary Mod
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From: Freaking Poland!!
Originally Posted by andrew lohaus
why are you so set on pure electric activation? the turbo is giving you free presure to open the acuators.........(they only need like 3 psi wich you should have by 2-3kprms anyway) aaron cake's sugestion seems ideal if clearance is going to bee an issue and you can do it a X pressure using a simple bleed valve instead of an electric pressure sensor.
id be surprised if the stock actuators even hold up sitting right over a turbo. no way any plastic/electric compoents willl survive there.
id be surprised if the stock actuators even hold up sitting right over a turbo. no way any plastic/electric compoents willl survive there.
Thread Starter
Joined: Nov 2002
Posts: 12,752
Likes: 1
From: Laredo, Tx
Originally Posted by andrew lohaus
why are you so set on pure electric activation? the turbo is giving you free presure to open the acuators.........(they only need like 3 psi wich you should have by 2-3kprms anyway) aaron cake's sugestion seems ideal if clearance is going to bee an issue and you can do it a X pressure using a simple bleed valve instead of an electric pressure sensor.
id be surprised if the stock actuators even hold up sitting right over a turbo. no way any plastic/electric compoents willl survive there.
id be surprised if the stock actuators even hold up sitting right over a turbo. no way any plastic/electric compoents willl survive there.
SPace is an issue. The actuators will not fit with a turbo smack dab in their way.
Originally Posted by 1987RX7guy
SPace is an issue. The actuators will not fit with a turbo smack dab in their way.
Thread Starter
Joined: Nov 2002
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From: Laredo, Tx
Originally Posted by andrew lohaus
true but, it seems silly to throw out the perfectly good pnumatic system for the sake of easthetics, besides a pressure switch would add as many wires as hoses it replaces.
Thread Starter
Joined: Nov 2002
Posts: 12,752
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From: Laredo, Tx
Originally Posted by rotarygod
I think a previous suggestion would be benefical here. Remove the stock actuators from the lower manifold. Run a bicycle brake cable with a split in it so one cable can run both actuator rods. Run the single cable to a vacuum actuator that has been relocated and been made to work. You'd still have the turbo clearance but you'd also have the working 6 port system. You'd also need 2 small return springs on the rod ends. Just find an appropriate location for the actuator elsewhere. People are creative here. Make it work. I used to have a bicycle brake cable running from my throttlebody to my omp.
I hope to do a lot of fabricating work during th eup comming thanks giving day holidays aswell as christmas holidays. I'll definatley try the cable pull style actuation if at all Possible.
Senior Member
Joined: Sep 2003
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From: Fort Worth, TX
I have my 5th & 6th removed. The VDI is wired open. I have nothing to back up if having them open is better than closed, howerver, the VDI chamber works as a plenum and the more volume of air I can get into the engine the better. I have it se at 10psi and I start getting boost by 4800 rpm in 1st gear and continue boosting through 4th gear.
