RJC boost controller with external wastegate?
- Thread starter rpk250
- Start date
Phoneguy
Cometic HG stress tester
- Joined
- Aug 27, 2002
Both.
The external gate has a spring that is rated at a certain boost level that will open the gate. The boost controller will let you control the amount of boost that gets to the wastegate. Lets say the wastegate has a 7 lb spring, without the controller your wastegate will open at 7 lbs. With the controller between the turbo and wastegate you can now control how much boost it takes to open the controller before the wastegate. Say you set to 20 lbs, the controller opens at 20 lbs allowing the pressure to go to the wastegate which only has a 7 lb spring, the wastegate now opens due to the 20 lbs being more than the 7 lb spring can hold. Now if you were to set the controller at 5 lbs it would open at 5 lbs buit would not open the wastegate until the spring rate of 7 lbs was reached but you will not be able to build more than 7 lbs of boost. Hope that was clear...
Bryan
The external gate has a spring that is rated at a certain boost level that will open the gate. The boost controller will let you control the amount of boost that gets to the wastegate. Lets say the wastegate has a 7 lb spring, without the controller your wastegate will open at 7 lbs. With the controller between the turbo and wastegate you can now control how much boost it takes to open the controller before the wastegate. Say you set to 20 lbs, the controller opens at 20 lbs allowing the pressure to go to the wastegate which only has a 7 lb spring, the wastegate now opens due to the 20 lbs being more than the 7 lb spring can hold. Now if you were to set the controller at 5 lbs it would open at 5 lbs buit would not open the wastegate until the spring rate of 7 lbs was reached but you will not be able to build more than 7 lbs of boost. Hope that was clear...
Bryan
williamsGN
'Horse sneeze' addict
- Joined
- Sep 20, 2007
If your external gate has a dial type controller for it, that is all you need. I mounted mine in the car so I could adjust it on the roll.
Turbonetics Boost Controller - Variable Boost Kit - JDM parts: Honda, Toyota, Nissan - Japanese aftermarket and performance car parts Universal
Turbonetics Boost Controller - Variable Boost Kit - JDM parts: Honda, Toyota, Nissan - Japanese aftermarket and performance car parts Universal
Yep, thats the controller that I have. I'm having some boost creep still, even at the lowest setting on the boost controller. The bost will start low, about 15 psi, but into 2nd gear and into 3rd it creeps up over 20psi. I hogged the wastegate hole on the turbo pretty good, I wonder if I need a stiffer spring in the wastegate?
williamsGN
'Horse sneeze' addict
- Joined
- Sep 20, 2007
Possibly, I have an old deltagate on mine and it stays locked at whatever I set it at. Check that all the hoses and tight and zip tied on the gate and controller.
jpwalt1987
Well-Known Member
- Joined
- Nov 9, 2003
I had to remove the RJC valve from my setup. I have a TiAL 44mm with a 10lb spring and a dial a boost controller. It would fluctuate all over the place no matter where or how I set it. Now it is rock solid without the RJC valve. Take it off and just use both ports on the wastegate and the dial a boost controller.
- Joined
- Aug 1, 2003
ove boost is what you have , creep is generally opposite like when the boost drops back
stiffer spring will only make overboost worse
rjc helps if you run a light spring and have slow spool
or if you wanted to run higher boost
, you need the gate to open more and thats usually not possible ,
check the gate outlet pipe and make sure its fully opened up where it goes back into to the downpipe , check the porting at the turbo and open the turbo and the pipes flange as much as possible
run a lower # spring , the spring rating is the minimum the boost will control down too
if that doesnt work you need a bigger gate and piping to it
stiffer spring will only make overboost worse
rjc helps if you run a light spring and have slow spool
or if you wanted to run higher boost
, you need the gate to open more and thats usually not possible ,
check the gate outlet pipe and make sure its fully opened up where it goes back into to the downpipe , check the porting at the turbo and open the turbo and the pipes flange as much as possible
run a lower # spring , the spring rating is the minimum the boost will control down too
if that doesnt work you need a bigger gate and piping to it
jpwalt1987
Well-Known Member
- Joined
- Nov 9, 2003
What brand of gate and what size is it? When you ported the hole on the turbo did you also radius the opening so the exhaust gas doesnt have to make a sharp 90 degree turn? Are you using the top and bottom ports of the wastegate? My wastegate is plumbed off of the front of the header. That is the best method BUT what you have should still work properly.
Update. Problem solved. I took the downpipe back off and made a stencil of the wastegate hole and transferred it to the turbo's wastegate hole. I was able to open the hole up a bit more, but I think the most important thing was smoothing out that internal radius. I took alot of material off in there and made that a smooth curve. Boost is solid all the way through the gears. Thanks for the help.
