Carrizog, at present the vanes in my VNT are easy to move. Okay now I understand. Yes my wastegate/boost can is from a T3 where yours is from a T2. When boosting on the gas hard(I have a open style muffler) the exhaust does get louder, but by no means loud. I have 2.5 inch exhaust from the turbo back.
I have a couple linkages that operate the VNT control and you could make it more or less movement depending on what you want. With my linkage I wanted it to be about the same movement that the control needs so maybe 5/8" or 3/4" (13 to 20mm) or about how much the linkage on the turbo moves. I tried to keep it 1:1. I have lots of movement on the boost can and the cable also has adjustment for length. Attached to the pump I have a plate bolted onto the throttle part that has a slot in it, so I can move the arc that pulls the cable either longer or shorter.
I'd say economy suffers in my case too as once you have a vnt its hard to stay off the boost. it's awesome...pull.
Carrizog, at present the vanes in my VNT are easy to move. Okay now I understand. Yes my wastegate/boost can is from a T3 where yours is from a T2. When boosting on the gas hard(I have a open style muffler) the exhaust does get louder, but by no means loud. I have 2.5 inch exhaust from the turbo back.
I have a couple linkages that operate the VNT control and you could make it more or less movement depending on what you want. With my linkage I wanted it to be about the same movement that the control needs so maybe 5/8" or 3/4" (13 to 20mm) or about how much the linkage on the turbo moves. I tried to keep it 1:1. I have lots of movement on the boost can and the cable also has adjustment for length. Attached to the pump I have a plate bolted onto the throttle part that has a slot in it, so I can move the arc that pulls the cable either longer or shorter.
I'd say economy suffers in my case too as once you have a vnt its hard to stay off the boost. it's awesome...pull.
the mileage decrease is from the user, not the turbo
I was just trying to change my vacuum can to a boost can that came with the VNT.(my t2 can doesn't move enough, have enough travel) I have a control linked to the throttle and am having much trouble sealing my vacuum can to add to this linkage.
I got thinking - why do I need a boost can in line with the throttle linkage. I know I've seen this setup on here. If you have a direct linkage without a boost can, simply set the linkage to what you want for boost at full throttle. The boost can will only back off the boost once you hit a certain point and will be very linear at doing that. It won't back off boost pressure just at max boost, it will back off boost pressure very linear to what you adding with your foot/accelerator pedal. With a direct linkage, which is almost what I have now, boost will be linear to throttle position. (t2 can only moves like .02")
I live on the prairies, flat area; I see no need for a boost can. I'm going to try a direct linkage and see how it works. Just thought I'd add this...
I was just trying to change my vacuum can to a boost can that came with the VNT.(my t2 can doesn't move enough, have enough travel) I have a control linked to the throttle and am having much trouble sealing my vacuum can to add to this linkage.
I got thinking - why do I need a boost can in line with the throttle linkage. I know I've seen this setup on here. If you have a direct linkage without a boost can, simply set the linkage to what you want for boost at full throttle. The boost can will only back off the boost once you hit a certain point and will be very linear at doing that. It won't back off boost pressure just at max boost, it will back off boost pressure very linear to what you adding with your foot/accelerator pedal. With a direct linkage, which is almost what I have now, boost will be linear to throttle position. (t2 can only moves like .02")
I live on the prairies, flat area; I see no need for a boost can. I'm going to try a direct linkage and see how it works. Just thought I'd add this...
because sometimes we have friends/families who need to borrow our vehicles, and they do not understand : keep an eye on the boost/egt gauges. lol
I put a knob on my dash so I could open/close the vanes,.. the the boost still backing them off as it moves upward.
With 2.5" exhaust and a muffler; it is alot louder with the vanes open at idle.
One of the main reasons I tied the vanes closed, on the last controller.
Instead of having the accelerator open the vanes at idle.
A friend with a 2 1/4" TT exhaust with borla has no problem with the noise off boost.
here is a free fully programmable open source VNT, or VNT+LDA controller. the source code is free, and the microcontroller is ~$35.
source code:
http://dmn.kuulalaakeri.org/vnt-lda/
open source microcontroller:
http://arduino.cc/en/Main/ArduinoBoardUno
That is seriously cool. If I ever do a new engine for Jezzie, I'm probably going to go the mTDI route, but I'd totally go for an electronic VNT/LDA controller!! Frankenengine indeed...
I got thinking - why do I need a boost can in line with the throttle linkage. I know I've seen this setup on here. If you have a direct linkage without a boost can, simply set the linkage to what you want for boost at full throttle. The boost can will only back off the boost once you hit a certain point and will be very linear at doing that.
Yeah, the pressure can actuator is a failsafe to prevent overboost, automatically backs the vanes off at a preset boost level... If you are conscious of boost & EGT you can simply use the pedal to regulate it, or alternately, install a blow-off valve to vent excessive, unsafe boost levels.
I've simply removed the can and installed a threaded rod to replace it so I have lots of adjustability. So Far I've got it set to a max of 20 psi on boost and under hard acceleration that's just where it stays. no problems overshooting at all.