spooledUP7

I just installed some needle valves for boost and control hello boost.

I'm not trying to overboost the engine, just hit a solid 10 to 11 boost. I spent a good hour adjusting the valves and so far I am pretty satisfied. I still need to flush out the transition a little more (11-5-10), but I think I'll get there.

I have a question for those that have done this mod before. Is your precontrol valve shut more than your wastegate valve? I want to get more precontrol but when I open up the precontrol valve more (1/16th turn) the primary gets starved and neither boost well. I'm a little afraid to close the wastegate anymore than it already is (1/8 turn open), but I kinda think that maybe these valves need to be adjusted 1/32 turn at a time. Does this make sense?

Anyway, it's nice to have control, even if I am only tring to get stock boost.

spooledUP7

I was asked in a PM about how much I spent on the controllers.
I spent $17 on the hardware. I picked up 1 10' roll of 1/4" copper tubing, and two 1/4" - 1/4" (with capture nuts) needle valves at a cost of $5.97 each.

I cut the silicon hoses in half that were already on the precontrol and wastegate control to splice the tubes in.
I mounted the valves on an aluminum plate that I made and then mounted it to the J-spec AST mount on the intercooler.

I also had some old guitar ***** that I put on the valves to help measure adjustments.

I did some more runs today and I still have not been able to get the 5psi dip out, but I have got it to blip bye very fast.

Just a note to anyone who might want to try this mod, it's not easy to find the right adjustment. The precontrol has more control over boost than you might think. Slight adjustments can cause some pretty radical changes. The wastegate is not so responsive but you can still see changes. The range between fully closed and fully open is about 1/4 to 5/16 turn from closed.
Right now I have the wastegate cracked at 1/32 turn out, and the precontrol now 3/32 out.

KZ1

you are porbably having probelsm with pre-control system. THe lower boost you see on TPC, the higher the spike or tranisstion. your TPC maybe leaking, etc. I woudl check it out. TUrn boost on primary to 5 lbs, it shoudl spike at transition. a dip of 5 is way to low, means TPC is not working. If you were getting say 15lbs on primary, well maybe 5psi dip is expectable depending on mods.

cewrx7r1

iTrader: (2)

Your new installed PC valve that replaced the pill only slightly affects the delay of the opening of the PC gate. To have more control over the PC gate, you will have to adjust the control rod length. This changes the required pressure to make it operate.

The later the gate opens, the lower the transition spike.
The more pressure it takes to open the gate, the more boost #1 turbo will build.

spooledUP7

I actually tried to adjust the rod length, but I couldn't turn the threaded end so I gave up. The rod currently lines up at about 3/4 exposed, which means it still is holding the door shut at 0 psi, but I can see how extra force would limit the PC from actuating until much later.

What happens if I close the WG all the way and use the PC to regulate boost?

FastX7

Can you put up any pictures?

spooledUP7

I'll try and take some later today.

thatoneguy

The mechanic at Tripoint said that the needle valves are bad and I should remove mine. Of course he didn't tell me why. I don't see what the difference between that and the pills are, except that the hose is usually much longer when you have needle valves.

KZ1

I woudl think that being a 1/4 off wouydl not cause a 5psi dip. 5psi, is the lowest the dip will go if properly boosting on both turbos. Basically you have bigger problems than just adjusting valves. Try putting the stock pills back in, and then shoot for the perfect boost pattern, so you can eliminate the valve system out. Maybe I am reading this all wrong. Why did you put in valves to begin with? what was your boost pattern before?

"but when I open up the precontrol valve more (1/16th turn) the primary gets starved and neither boost well. "

this will always happen. If you are getting high primary, but low transition you have problem, not adjustment. If you are getting low primary and not a high spike then you also haev a problem.

spooledUP7

My best guess is that it adds more complexity to the scheme of things. With any thing, there is always the chance of failure kinda like an 0-ring on a 2billion dollar space shuttle. It looks good on paper.

I installed the boost controllers becuase I felt like having control. As for boost patterns before, I had the pills swaped and I was getting some funky patterns, but I decided why not install the controllers since I always wanted to. It was a good excuse for me.

I may put the pill back in if I can't fix the dip within a short period of time. I am going to hook my boost gauge to the secondary turbo to see if I am building 8+ pounds before 4500.

Then I am going to checkout the charge control door and see if it is completely shut.

It's not bad as far as the dip goes. I could live with it since it only down there for a split second. It's not like I have to build back up to max PSI after the transition

racer rx

Speaking of pills: I am currently running a stock 59 jet in the pre-control. And a 67 in the Wastegate line.

Getting 12 - 13 - 13 pds.

I have a street ported engine w/wastegate ported a little too.

I wanted a little more from the First turbo... Can I put a 60 jet into the Pre-control line? What should I expect?

Will this give me a little more from the first turbo? I want a little more go... at 2500 - 2800 rpm. With the street ported engine there is a little lag.

Any suggestions?

Was planning on adding a Turboxs standard boost controller in the spring as well... Comments anyone?
jack.

OneBadRx7

I did only the boost control mod, not the pre control thingy. I opened the valve all the way open to start my tuning session, turned out I hit a max of about 14psi with the valve all the way open, man what a open exhaust will do for this car. I was spiking to 15+ before I did this mod, glad I did it, I dont go past 14 now so I know I am being a bit more on the safe side, for $6.50 and a half hour of my time I would say it was well worth it,

spooledUP7

The precontrol thingy is really as affective as the turbo control valve. I think that the precontrol has more range of control.

jpandes

With a shorter hose there is much less restriction in the lines. Since the hose is shorter, the wastegate will be able to open and close much faster and bleed off the excess boost quicker, giving you much better boost control.

I know this because I had a Home depot needle valve and 6 feet of 4mm hose to control my boost. After installing a high-flow cat and a Large M2 Smic I was hitting 15+ PSI with the needle valve wide open! I also tried to restrict exhaust flow with a restrictor plate(w/ a 2.25" hole) with out much better resullts.

I finally removed the HD Boost controller setup and replaced the 4" hose to the wastegate solenoid(NO PILL) and now I am hitting a solid 9.5 PSI. I am going to now try and remove the restrictor plate. I'm hoping that I see less than 13.00 PSI...

SPOautos

I had my wg line just barely open, what I did was adjust the pre spool to get it where you want it and clsoe the wg to keep boost in the pri turbo. This worked very well for me. I ran a solid 12psi of boost with a .5 or so psi spike during transition. Running a .5psi spike thru transition gave the best response. Thats what I would go for, if your running the stock computer tune for 10 or so psi of boost with a .5spike thru transition. You'll love it!!!!!

STEPHEN

SPOautos

Oh yea, now that I think about it when I said my wg was barely open that when I was running like 13 psi of boost. Yours prob need to be open a good turn or two. Just play around with it, open the pre spool to get more of it and close off the wg to keep the boost up. I usually made my adjustments in 1/4 turn increments

STEPHEN

RX7Elmo

to make roughly 11 psi, the main boost control valve shouldn't be almost closed. more like 2 full turns from closed. FYI, mine does 5 full turns. The precontrol should be about 1-2 turns from closed position..maybe..i dn't remember. The pre-control does a lot, it can make the primary boost more or less, control the spike and control how much boost you see after transition.

Also what are these 'pills' people talk about. stock pills, aftermarket pills? i didn't see any pills in the hoses when i took them out from the wg or precontrol?? Any pics would be helpful