Boost Controller Questions

[jskarateka]

I have a GN1 downpipe with external gate and a turbonetics boost controller hooked up like the 3rd diagram in the attached picture. If I tighten the knob I get more boost. Trouble is, if I want 25 lbs it spools up fast to about 21 then creeps up to 25 over the next 2-3 seconds (long time when on thedrag strip) then it will hold steady. I checked for exhaust leaks and didn't find any.

If I remove the T and controller and run the hose direct to the bottom connection of the external gate, and leave the top connection open, I get about 7-8 lbs like I should.

If I remove the T and controller and leave the hose off the bottom connection of the external gate, It will spool quickly strait to 27-28 lbs, at which point I lift the throttle.

Question 1:

I was going to try switching to the configuration in the 2nd diagram, but I read that it does not control boost as well as the way I have it now. Looking for opinions on that, and if it may help.

Question 2a:

I currently have the controller connection with the arrow pointing outward, going to the top connection of the external gate. If I switch to the configuration in the 2nd diagram, does that same controller connection with the arrow pointing outward go to the bottom connection of the external gate?

Question 2b (Bonus Points)

Sorry but I'm trying to understand exactly how this works and it's driving me nuts. The way I see it if I set up like the 2nd diagram, depending on how tight the knob is the boost bleeds through at some point (say 25lbs) and overcomes the spring pressure to open the gate. I get that.

But if you move it over to the setup in the 3rd diagram, it wouldn't bleed any pressure through to help the sping untill a certain point (say 25lbs), but by then the gate would be open at around 7 lbs and I would never get there. So what am I missing? Am I just way off on all this?

Thanks Guys.

 

[jskarateka]

After some testing, I can see the controller does not work they way I thought it did. No surprise there. I have been trying to configure it for tuner style as in the second diagram with no luck. Do I need a different conroller to run it that way?

Anyone? anyone?
Buuuueller?

 

[TurboBob]

i think you are likely fighting backpressure effects limiting you to 21 controlled normally, and its creeping to 25.

I would start with a heavier spring. say 13 psi, and use the 3rd connection method. You may need to port the wastegate hole in the turbo or look into
the discharge pipe that is routed back into the downpipe, as sometimes the hole in the DP is restricted.

with a gate like that, running the discharge out to atmosphere has advantages as far as solid boost control, and perhaps some performance.

Bob

 

[jskarateka]

Bob, can you elaborate regarding the back pressure? Do you mean back pressure through the downpipe/exhaust, or back pressure through the wastegate/discharge pipe?

I don't really get any boost creep at a lower setting, say 17lbs. Seems to only be if I'm going for 25+.

Even when I have the controller screwed all the way in, I only get about 21 then creep to about 24-25. It will spool strait up to 28+ though with the bottom wastegate hose connection removed.

Regarding the spiring, is taking it out and stretching it out a bit a bad move, as opposed to ordering a new one?

Thanks Bob.