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-   -   Non sequential over boost problem (https://www.rx7club.com/3rd-generation-specific-1993-2002-16/non-sequential-over-boost-problem-878647/)

Force13B Dec 18, 2009 04:35 PM

Non sequential over boost problem
 
I've been battling this for about a month and i'm at a loss. I'm getting 1.01 bar at 85% throttle with boost controller set to .5bar and 20% duty cycle. At first i thought it might be caused by boost creep so i ported the wastegate, that didn't help.

Then i thought maybe my WQ actuator was sticking so i replaced that, that didn't help.

I then thought the way my boost controller was setup was the problem.
I have an AVC-R but this pic works. I had my wastegate going to comm, and the prespool looped back in. like so
http://i23.photobucket.com/albums/b3...ollerfirst.jpg
I thought this might be causing the problem so i swaped back to the old way see pic
http://i23.photobucket.com/albums/b3...KS_diagram.jpg
I have caps on the other side of the WQ and prespool

Then i thought maybe my boost solenoid was going bad so i disconnected it so that i should get 7psi just on spring pressure and i'm getting 1.01 bar at 70% throttle :scratch:


I have a full 3in HKS carbon Ti, 3in midpipe, HKS dp, Haltech platinum 1000, all the block off plates, AVC-R boost controller (that is wired correctly) and worked fine before i went to 99spec turbos and rich mans non sequ.

I have a fuel system and meth kit waiting to get installed. I could through that stuff in and i can say screw it tune to whatever boost the car wants to run. At this point in time it's kind of like 1 of those puzzles you get for your birthday or christmas where it pisses you off and you want to figure it out. Any help would be greatly appreciated.

arghx Dec 18, 2009 04:56 PM

3 Attachment(s)

I have an AVC-R but this pic works.
That pic shows a stepper motor and you have a 3 way solenoid valve. They work in a completely different way. Leave the precontrol out of the plumbing completely. You have the door forced wide open right? Same with the turbo control? Plumbing should be this:

https://www.rx7club.com/attachment.p...1&d=1261176875

and here's how it works. The solenoid cycles on and off rapidly, and a higher duty setting will increase how much it is cycled on. Every time the solenoid is cycled on, the pressure signal to the wastegate is blocked, and the pressure in the wastegate actuator itself is vented.

https://www.rx7club.com/attachment.p...1&d=1261176875

https://www.rx7club.com/attachment.p...1&d=1261176875

Also, turn your feedback speed down in the AVC-R for now. Set it to like 2 for now. You can increase that later if the boost is tapering off too much up top.

Force13B Dec 18, 2009 05:04 PM

Apexi solenoid is 2 valve. At first i had just the WQ hooked to Comm and the prespool running to pressure source, then had WQ and Prespool hooked to Comm, and Pressure source hooked to No, thinking it would help
http://www.rhdjapan.com/images/produ...mal/Image1.jpg

Not that it matters because when i disconected the boost controller to run on spring pressure, which should give me 7psi, i was getting more poost at a lower throtle positions

Force13B Dec 18, 2009 05:05 PM

I also ground out a bunch of mettal from behind the WQ flapper so that it could open farther.

arghx Dec 18, 2009 05:09 PM

It's a 3 way solenoid valve. The stock solenoids are 2 way.

http://www.extremepsi.com/store/images//t_21436.jpg

you need to cap the other nipple on the wastegate actuator. the "prespool" should not be hooked up at all. By hooking the wastegate actuator to the precontrol you are reducing pressure in the wastegate actuator, which will raise the boost.

Force13B Dec 18, 2009 05:36 PM

The other nipple on WQ is capped. So both nipples on the prespool should just be open?

arghx Dec 19, 2009 09:54 AM

please read my thread on how the sequential turbos work: https://www.rx7club.com/3rd-generation-specific-1993-2002-16/why-engine-so-damn-complicated-part-1-sequential-turbos-demystified-841821/ . at least read the first part where it discusses turbo control, precontrol, and charge control valves.

if you did the non sequential conversion correctly, the precontrol door should be forced open and the precontrol actuator completely useless. So you could cap them or just put nothing on them. The whole point of the precontrol actuator is to move the precontrol door in a sequential setup. But that door should already be forced open now since you are non sequential.

Plumbing the precontrol actuator into your boost control just reduces the amount of air reaching the wastegate actuator, which is certainly not going to help boost control.


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