You can type here any text you want

How come can't boost over 12 with no contoller?

Welcome!

By registering with us, you'll be able to discuss, share and private message with other members of our community.

SignUp Now!

tb3

elbows & a$$holes
Joined
Mar 31, 2006
Messages
2,716
I bought a used rjc boost controller for my 86 T. My factory controller was working fine, but I got the rjc cheap cause the guy said it caused him to blow a head gasket, so's I figured if I got it working right, it would be cool to get rid of the progressive boost thing with the factory one. I hooked it up last night and couldn't get the boost down, I did a search and found that sometimes you have to trim the spring. I didn't have time to, so I just removed the spring and ball, hooked the hoses back up and figured I would be safe today driving it to work because now theres always going to be pressure pushing the wastegate so no worry of overboost. I got into the boost on the drive in this morning, and I was able to get 12 psi ???, and that was it. Is it only 12 because of the size hole in the 90 elbow on the compressor? where is the restriction that keeps it at that #? With no ball or spring in the controller, I've now just got a hose going from the wastegate to the compressor. What will allow the wastegate to get over 12 psi once the ball and spring are reinstalled and sized correctly?

This is probably a common question, but couldn't find any info on search.
tia

I did get the instructions with it and I'm confident I have it hooked up correctly
 
If you are using a stock actuator, you will overcome spring pressure at 12 psi and it will open the flapper. By taking the spring and ball out, you have basically made a "blow through" brass valve with no guts.

If you have a HD actuator, which I believe can be opened at 18 psi - then you have given it a direct line to boost pressure (with no way to regulate flow).
 
ahh.... stock actuator spring pressure, now its making sense. I've just trimmed the spring, I'm going to install and see what happens next.

btw,

I will probably buy a couple more manual controllers for my other buicks. the rjc controller is $49. this one is $11 with shipping

eBay Motors: NXS MANUAL BOOST CONTROLLER TURBO GSX GTI RSX RT/TT MBC (item 250169629128 end time Oct-01-07 12:41:44 PDT)

Would I be ok just getting that one? or is a get what you pay for kind of deal?
and thanks for the reply
 
The RJC valve actually has some engineering involved in it. Well worth the cash IMHO.

Here's another question. Do you still have the factory wastegate solenoid attached?

Do you still have the little gray restrictor "y" in line with the wastegate plumbing?

If the "y" is still in place, you essentially have two restricting devices in series. Remove the "y".

If the factory solenoid is still being used, pack it away in a box and run all plumbing directly from turbo/wastegate to RJC valve. Some say you will get an SES light without the solenoid, but I have yet to see it come on.
 
thanks for the replys carlo

I did completely remove the boost hoses with the y restrictor before installing. I left factory solenoid hooked up, I had knew about the engine light. I'm going to remove the solenoid, cap and label the wires and shove them back into the harness after I have turbotweak update my chip.

I just got back from lunch. I cut just the bottom coil from the spring (so that probably shortened the spring not even 1/16th. I started out with threads barely in. only got 12psi, then turned it in bout 3 times, and was right at 16psi. The car knocked off a killer second gear scratch and hauled some pretty good rear (for my mostly stock car). That made me feel pretty good. I don't have scan tool with me so I backed it off a half turn so I'm at 15 psi, which is about all I can get in the warmer weather. so....success!!!

I noticed that from a roll, when I hammer it to wot, the boost very quickly goes to setting I've got it at, then quickly rolls off a couple psi till it can catch back up with itself. is that normal?
 
and about the ebay controller. RJC claims that their controller works with all other turboed cars as well, and the one on ebay also makes same claim. What I'm getting at I guess is,... how much more, and better engineering is involved with rjc's compared to that one on ebay? All we're talking about is a simple orifice, spring, ball, and manifold. I don't want to skimp and cost me big $$$ in the long run, but,...Is there differance in quality of metal? tolerances? thanks in advance for any input you have.
 
It's not that either one is engineered better, it's that Jason's part is proven for the TR. I don't think I have ever heard of anyone needing to cut the spring on the valve. Does your wastegate have a threaded rod for adjustment? Make the adjustment there and use the rjc valve to control the "leak".

I may have made a mistake. IF you disconnect the solenoid you will get the ses, if you leave it plugged in, no light.

Keep asking questions, and we will do all we can to answer.

Dan
 
I kept the solenoid plugged in, and will leave it that way till I get my chip updated. I haven't even bothered unplugging it to check if it does make it come on. I'll try it just for curiositys sake.

I went through a bunch of threads on here last night and found that a couple people had issues with their spring inside the contoller being to short or to long. They where advised to cut or stretch it, whichever their case may be wheather it was couldn't adjust down boost or vise versa.

The wastegate is a stock wastegate and I cut and threaded it myself so it is adjustable, figure that should be fine with no more boost than I run. The instructions for the controller said to adjust my rod so that I only have to pull it 1/8 inch to get it on the gate. I did do that. Should I screw out the controller a little bit (which would pull boost back down), then adjust (shorten) the rod till I'm back to my 15psi destination? and would that possibly do anything for that temporary boost roll back?
 
I few years before RJC started selling their version I bought one of these. Hybrid Boost Controller It worked fantastic. Rock solid boost, quick spool, just a terrific controller. The only reason I stopped using it was because I went to an electronic unit.
 
That site references dawesdevices. That's who I bought mine from and then they changed to 3barracing.
 
That HBC one you linked looks exactly identical like the rjc one black bandit.
Thanks for the link LQ. i can't say I really see any need yet to incorporate the factory solenoid back into the system, but I've only drove it home so far, I'll definetely check into that if I notice anything annoying with the driveability of it in the future.

Where does everybody mount their controller? I didn't see any way to mount it other than tie straps, so I just mounted it to the fuel line with a piece of hose inbetween to prevent any chaffing of the fuel line or the controller. I didn't really want to lay it across the turbo like RJC shows in their picture
 
same issue here

tb3 and Notacarlo, I installed mine last night and can't get above 15lbs of boost. I have an HD actuator rod that previously had been set at 19 - 20 psi. If I understand you guys correctly, I need to back off the HD rod all the way back to say 12 psi or approx 1/8 of an inch in order to attach to the WG?

The factory "y" has been removed and the unit has been installed inline between the compressor and wastegate actuator as per the instructions. Spinning the boost controller in/tighter didn't see any gain or increase in boost.:confused:
 
my problem was too much boost, and couldn't bring it down. So I shortened the spring. In my searches I did, I found some guys who couldn't get enough boost, so they had to stretch the spring. Which in my opinion royally sucks for them. I would think you can get away with shortening the spring and not have a issue with it messing with its specific pressure rating, but stretching it I would think start messing around with its contortion rating. I would go ahead and adjust your wastegate rod per instructions to where you have to only pull it 1/8 inch to get it onto the gate. then see where that gets you, keep a very close eye on your boost. All I did was adjust it (controller) to where I was getting my desired max boost at wot. If you've taken the contoller apart, make sure you have installed the ball back in correctly on the correct side of the spring.
I'm kind of a novice, so you may want to wait for some second opinions.
 
I ended up getting multiple springs to play with from a local tranny shop. Worked really well with a stiffer spring. Mind you I am an alky holic, so there you go....:smile:
 
I ended up getting multiple springs to play with from a local tranny shop. Worked really well with a stiffer spring. Mind you I am an alky holic, so there you go....:smile:

I may have to try a different spring as well. I'm approx 3 turns of adjustment left in the boost controller before it's maxed out. I'm at 18psi now and would like to see 24 or 25#. I too am an alky holic:cool:
 
What turbo are you running? If the wastegate hole is ported fairly big, you will have to tighten the wastegate rod more to keep the puck closed. I am out of adjustment with my grainger valve as well, and then start tightening up the wastegate to get more boost out of it. If the rod is too loose, the puck will push open no matter what the boost valve is set at.
I only have a normal wastegate rod, and 24 psi is all she's got....
 
...got it. so if I screw in the HD actuator arm..boost should increase. I'll give that a shot. The rod was set at roughly 13 or 14#'s. I was thinking that I would get another 10#'s with the controller added to the 14#'s where it was set previously, to get a total of 24 which is where I want it.

I'm running a TE-62, GN-1's, TT/Alky setup, 206/212 roller, V2, and Vig 3500.
 
I've used this Grainger check valve (about $10) since Feb. on my turbocharged VW air-cooled motor.
It's allowed me to get 18 lbs. of boost out of a wastegate actuator that's set up for 10-12.
Set-it-and-forget-it accuracy and repeatability.
I couldn't be happier.

As for tuning it, I started out with zero tension on the spring/poppet ball and slowly tightened it to increase boost.
Personally, I wouldn't go trimming the spring.....I think it's good for 0-20 PSI right out of the box.

Bill
 

Attachments

  • Buggy Grainger.JPG
    Buggy Grainger.JPG
    59 KB · Views: 189
Mine has a bleed hole right at the exit of the valve (about 1/16" or so). Without it, I would get boost surging back and forth.
 
Back
Top