silverflash2

iTrader: (2)

I have a ball and spring manual boost controller and had it installed a few months ago. And i'm currently running 8 lbs of boost till the second turbo kicks then hit 13 lbs and stays. Any adjustments on the contoller only effects the second turbo. My mechanic says i need another one for the primary. I never heard anybody running 2 manual boost controllers ? Was i suppose to get 2. It kind of make sense since it's hooked up to one waste gate. Not sure if it's hooked up right or i need another one !

adam c

iTrader: (2)

I have never heard of anyone using a separate boost controller for the primary. I am not sure how, or where, you would do that.

A typical 2nd controller would effect pre spool. I would not recommend installing one.

spurvo

So the ball and spring controller you have is effecting the wastegate only, right? Likely, then, the restrictor for the pre-spool was removed, but NOT replaced by either a valve or new restrictor. adam and I have both had troubles trying to dial in the pre-spool with manual bleeder valve controllers, though I beleive damien had good results when he used ball and spring (Dawes devices, I think) controllers for both pre-spool and wastegate control. He has a nice write up in the archive section.

What's happening in your case is the primary turbo is spooling to 8 lbs, the unrestricted pre-spool circuit is limiting boost to this 8lbs until 3000 rpms or so, and then all the boost is being transferred to the secondary to pre-spool it. If you were to place a restriction in the pre-spool bleed-off circuit, you will see higher primary boost. HOWEVER, you will likely see a drop in boost at transition, though the ball and spring controllers are supposed to be fast enough that they mostly mitigate the transition drop. Supposedly.

Anyway, what I don't know is the reccomended restriction size for the pre-spool. I suspect you will find it here if you search.

I think I got that right.... try visiting http://www.autosportracetech.com/RX-7/rx7stuff.htm for more info on turbo troubleshooting!

spurvo

Found the sizes for the restrictors at

https://www.rx7club.com/forum/showth...34#post1770334

hope this helps...

silverflash2

iTrader: (2)

Thanks for the reply's. Still alittle confused in what i need to do do fix this.I thought the pre -spool controller valve was for the transition to keep you from getting boost spikes.I don't ever get boost spikes. I don't even get a drop in boost.

silverflash2

iTrader: (2)

So i should try changing the pill

silverflash2

iTrader: (2)

The hose with the pill was replaced with the boost controller. I didn't install this my mechanic did. So you think it's possible that i have the wrong pill size?

TwinTriangles

You can run one controller for boost control and another for pre-spool control as adamc stated above, I heard it was tricky getting them set correctly

adam c

iTrader: (2)

Both lines came with pills in them, unless your pre spool came with a nipple restrictor instead.

The boost controller replaces the pill in that line, so there shouldn't be a pill there any more.

silverflash2

iTrader: (2)

Thanks spurvo for the info,
I starting to make sense after i read your post 3 times. i'll buy a pre- controller and give that a shot. I would like to run 12 or 13 lbs of boost on both turbo's. i do a search to where i can buy one and how to dial it for those results. Thanks again