VNT control design problem

[camboscams]

1.6l Vnt 15 with intergrel exhaust manifold
So pardon my wonderful paint drawing, but here's the setup. i designed the original system using libbys more recent design with the boost can inline, but i realized the can would push the lever to a higher boost position. so this is what i came up with and i'm not crazy about this  setup, i feel that it will have too much slack and be hard to adjust.

Its drawn from the front of the engine



My other option was to put the can under the turbo with a slot that allows for vane actuation that slips over the vane lever and pushes it up to decrease boost. but i don't know cause if i'm at say 50% vane position and i've hit my target boost or more i don't know if the boost can will push far enough to control the boost pressure. but this system will eliminate my above duel lever system and make it potentially more adjustable.

So i guess what im looking for is if someone has a better system that would work for my setup

Thanks, Cambo

[camboscams]

Does anyone have any input? i'm currently putting 2.5" exhaust on it and i'm getting ready to finish the linkage system soon and hope someone has some input

Thanks

[wdkingery]

Hey dude I sent you a pm.. Sorry I don't have input on this situation, as I have not installed my turb yet

[camboscams]

Hey dude I sent you a pm.. Sorry I don't have input on this situation, as I have not installed my turb yet

Didn't get anything maybe try sending it again?

[tdihuntdawg]

hello, I don't know if I'm following you on using the can to increase or decrease boost? in my system the throttle closes the vanes boost goes to controller set at 18 psi then to can where it opens vanes once open the amount of fueling determines boost. I followed Andrews suggestion and attached my boost can between wheel and vnt lever. if it working backwards for you attached it the other side of the wheel. you can get it to pull or push with a clockwise rotation. things to consider #1 try to keep it in a straight linear pull the vnt lever is semi fragile.#2 measure the travel of vnt lever and gov. lever so you can figure ratios and know where to drill your wheel.#3 take care not to top or bottom out vnt linkage with heavy foot.#4 use rod ends and I used a shoulder bolt and brass bushing for wheel pivot. I am real happy with the set up ,I get instant boost off idle then it switches and your jammin in the 4750 lb. vanagon. you can Cruz at low boost but when you put your foot in it you got instant boost. and do use the slotted throttle return design. I found a long coupler nut to be handy for this. i will try to post photos ,

[rodpaslow]

Just a warning as I just installed mine - as per libby's design but I found out this weekend that the lever on the turbo is exactly backwards - the vane lever when it's closest to the ground is in the highest boost/ vane position for full throttle high boost application.  When the lever is up towards the hood/bonnet of the car it's in its lowest boost / low boost.  I am currently using a cable and need to reverse it somehow. (one peice manifold vnt 15)

What I see of your drawing will be incorrect as well if you want high boost at full throttle.

[camboscams]

Just a warning as I just installed mine - as per libby's design but I found out this weekend that the lever on the turbo is exactly backwards - the vane lever when it's closest to the ground is in the highest boost/ vane position for full throttle high boost application.  When the lever is up towards the hood/bonnet of the car it's in its lowest boost / low boost.  I am currently using a cable and need to reverse it somehow. (one peice manifold vnt 15)

What I see of your drawing will be incorrect as well if you want high boost at full throttle.

yea i was almost finished with the system and realized it. it was kinda a mind bender at first. i thought about using cables, and mounting the pulley on the end of the boost can below the turbo and having a spring return it to the less boost setting (its vague i know) but i'm to far into the linkage setup to do that.

Yes a wheel would work well, i like that idea! good advice on the vane lever not bottoming out. however my drawing is correct. when i step on the pedal the rod moves towards the front of the car pushing the vane lever down towards the more boost position. (thats why the 90 degree lever is sitting the way it is.)

[camboscams]

I don't know if I'm following you on using the can to increase or decrease boost

So when the boost raises to my desired amount it goes through my dawes valve boost controller, and makes the boost can rod come out it pushes on the lever that is hinged in the middle and attached on the other end to the pivot of the 90 degree lever, and in turn pulls the vane lever up to move the vanes in a less boost direction. hope this clears it up, its strange i know thats why i want input 

Thanks!

[rodpaslow]

On second look I don't see why that won't work.  I just question why you wouldn't put the boost can on the control lever itself as there's lots of room at the back of the engine once the VNT is installed.  that way you don't have to build something so the pivot moves with the boost can.  Good stuff - look foward to hearing how it turns out!

[fatmobile]

 If you put the boost can right to the lever,.. then that's the only input going to the vanes,...: boost pressure..

  This is one way to add another mechanical input,.. the accelerator position.

[camboscams]

If you put the boost can right to the lever,.. then that's the only input going to the vanes,...: boost pressure..

  This is one way to add another mechanical input,.. the accelerator position.

I'm sorry but i don't think i follow you

[fatmobile]

 I can't explain it any simpler.

[tdihuntdawg]

hello, you are right about vane control working opposite. the euro vnt -15 closes in the up position , the alh integral manifold vnt-15 closes in the down position. the adjustable stop is the closed position. the open stop is a pin inside the mechanism. I'm trying to help bobosan design his system . what I would do is modified the vacuum can to a boost can as per libbys vnt vanagon and then use it in the stock location and mounting. at the top of the linkage just past where it attach to vnt ARM weld a 1in. tab .bolt a rod end and use the wheel design to close vanes.try to keep it directly inline. with full throttle wheel rotates and rod pushes down to close vanes,boost in can pushes up ,the wheel is allowed to rotate back by the slotted spring mechanism.

[camboscams]

hello, you are right about vane control working opposite. the euro vnt -15 closes in the up position , the alh integral manifold vnt-15 closes in the down position. the adjustable stop is the closed position. the open stop is a pin inside the mechanism. I'm trying to help bobosan design his system . what I would do is modified the vacuum can to a boost can as per libbys vnt vanagon and then use it in the stock location and mounting. at the top of the linkage just past where it attach to vnt ARM weld a 1in. tab .bolt a rod end and use the wheel design to close vanes.try to keep it directly inline. with full throttle wheel rotates and rod pushes down to close vanes,boost in can pushes up ,the wheel is allowed to rotate back by the slotted spring mechanism.

Thanks for the input! I was hoping someone would chime in again. yea the more i think about my previous drawing the more i dislike it. too much room for slop.

So for the slotted tab bolt that threads onto the vnt arm, any ideas on how to make it? and still have the linkage from the top attach and not interfear with the rods slideability? that's the only thing that i can't quite figure out.

Thanks

[camboscams]

Bump any ideas?