Boost Controller = Less Low End Response Than Stock Solenoid

[mosquitocoils]

Hey guys.

This is something that's doing my head in at the moment... I've read pages and pages of info from all the manual boost controller threads and how to run high boost mode all the time with the stock dual stage solenoid...

My car had a turbotech controller on when I bought it, running 10psi, all good. Just for learning experience, I removed that and set up the stock solenoid again but earthed it out so it ran 7psi all the time. Now even though it was less boost, I felt a BIG difference in low end response. It picked up and got going a lot quicker, but once it was moving... well you could feel there wasn't much top end power.

So I put it back to using the boost controller with no solenoid.

Now I've read in 2 or 3 places (but can't find the damn threads/web pages again!) that by plugging the return line to the intake (from the t-piece) it may change the richness. I can understand that, as air that was originally going to be bled off by the solenoid back to in front of the turbo, is no longer there, and has just been bled off by the boost controller.

I now have an R32 actuator in and I tried hooking up all the lines to the solenoid again to bleed off another 2psi and get 11-12psi..... but it won't go over 10psi, and still feels a bit slow down low. I've checked all the vacuum lines and replaced all of the ones in that area (intercooler->actuator/solenoid/return line) with new 4mm hose. Would the diameter of the hose make ANY difference at all?

I have no 'restrictor' in the lines anywhere, which there apparently is from stock.

Can anyone help explain whether this is an actual phenomenon or whether I'm just imagining this, and maybe shed some light on how I can get rid of the sluggishness? Other than 'put back to stock' or 'ecu + tune'... because I've felt it run well before with the gear I have.

Thanks for your help!

[Sheriff Wan]

Dont you need to adjust your controller to allow more boost - screw it in or out?

As you stated the boost was set to 10 psi when you first had the car - put the boost controller back on = still 10 psi......

[mosquitocoils]

But I want 10psi while still having the factory solenoid plugged in.... that's my entire point. While using that setup my low response was GREAT, felt like a different car.

So I figured use an R32 actuator, use the stock solenoid, and have 10psi+response..... then 12psi @4500 as usual.

[STATUS]

it must have been plumbed wrong, the turbotech always bring boost on quicker than the std arrangement.

[mosquitocoils]

How could it be plumbed wrong if I was getting 10psi with it installed? Wouldn't it only open at wastegate pressure, or something totally different, if it was plumbed incorrectly?

[STATUS]

  mosquitocoils said:

How could it be plumbed wrong if I was getting 10psi with it installed? Wouldn't it only open at wastegate pressure, or something totally different, if it was plumbed incorrectly?

i could put a hole in the intercooler and still set it @ 10psi it would just be laggy and taper. i have seen those things plumbed wrong on numerous occasions. I bet you haven't isolated the std boost solenoid correctly from the bleed valve circuit..

[mosquitocoils]

When I bought the car, it had the turbotech installed. When I changed back to using the standard solenoid, I had more response. I then changed it back to the turbotech, and lost the response. I've NOW gone back to using the standard solenoid with the R32 actuator... but don't have the response this time. Everything is plumbed correctly, I'm sure of it.

[STATUS]

  mosquitocoils said:

When I bought the car, it had the turbotech installed. When I changed back to using the standard solenoid, I had more response. I then changed it back to the turbotech, and lost the response. I've NOW gone back to using the standard solenoid with the R32 actuator... but don't have the response this time. Everything is plumbed correctly, I'm sure of it.

well something isnt right ive got countless pages of dyno files and seat of the pant experience proving the opposite of what your saying. Without seeing pics of the installation i cant comment any further.

[mosquitocoils]

Yeah, no problems... I'm not trying to argue, merely trying to understand. I'll get some pics when I get a chance and see what everyone thinks. Thanks for the help so far!

[KiwiRS4T]

Your front mount won't be helping your response with a stock turbo. You should have no lines connected to your solenoid. Feed from boost pipe goes to turbo tech and bleed goes to bov return pipe (you have got a bov return pipe?) and the other line goes to actuator. Set the desired max on your turbo tech. If that doesn't work throw away your turbo tech and replace with a plain T (still with no pipes going to or from your solenoid) and put a restrictor in the bleed line the stock one will do but if you can't find it or someone has thrown it away you can just block off the T with solder and drill increasingly larger hole in it until you get the desired result.