boost problem
 

I have installed my rebuilt twins and I installed a HKS downpipe . The exhaust system is 3 1/2" all the way thru but now my boost jumps to 15 or 18 with the manual boost control closed all the way. What is the problem is it the DP or do I need something else to control my boost.
My car is stock besides the exhaust, under pulley, cool air intake, boost & temp gauge and now the manual boost control. Help me out guys I want to have it running good for spring. Oh and its an automatic.

What do you mean, manual boost control "closed"? Are you talking about the valve that you replaced the wastegate pill with? (do you have one on the precontrol too?). That valve should not be closed. Open it up to reduce the boost. What happens when you open the valve? 18psi will kill your car quick I think. Have you read all this stuff:

http://www.rx7turboturbo.com/robrobi...boost_note.htm

First of all... what type of manual boost controller did you install?? You forgot to mention that little fact. Second, How familiar with the three controllers and what they do are you? Third, do you have access to Mazda manual? fourth, did you RTFM and understand it before installing said controller??

its one of those home depot boost controllers. I opened it a little and it was at 18 and kept closing but no change.

No, no, no, no....
 

Open it before you go BOOM! With the valve all the way open, you see about 7 or 8 psi. Close it slowly until you see 10-11 psi.

You really gotta check this stuff out before you cost yourself some major $$$$. Maybe you got lucky this time.

Jeff

Do I need one on the precontrol or just leave the pill there? Thanks , that might be my problem . I thought the more air goes thru the line , more the boost so it is backwards right. I will try this tomorrow to see if it fixes the problem. Thanks again.

First or all... if you want to save you motor from BLOWING UP, READ ON CAREFULLY !!!… as you look at your engine bay, from the passenger side fender, find your INTAKE HOSE. THAT’S THE REALLY LARGE BLACK ONE … Located under the INTAKE hose is your PRIMARY TURBO.... You should see 2 "Metal Vacuum Nipples"... They're the metal ones by the turbo Flange. There’s a UNION at this juncture, which goes to your “Y”pipe. And, that’s were you initially removed those 2 black skinny hoses (OEM skinny STOCK ONES), 1 short and 1 longer one. They're designed to send boost/vacuum signals from the primary turbo via those black hoses (if they're still OEM stock) to your WASTE GATE ACTUATOR and the PRE-CONTROLLER ACTUATOR. Those are the 2 VACUUM POT Appearing things that have linkage rods coming out of them that disappear into the turbo area. Now, The Waste-gate CONTROLLER controls HOW MUCH - EXHAUST - gas is shunted to your PRIMARY TURBO, which, inturn CONTROLS HOW MUCH your turbo spools up and, how much BOOST YOUR PRIMARY TURBO WILL MAKE !! That Actuator is the top one. The lower or (MIDDLE) ACTUATOR) is your PRE-CONTROL ACTUATOR. That actuator controls the exhaust gas to your secondary turbo (Rear Turbo).

BTW Those skinny black lines HAD metal "B B's" in them that are center drilled. Those are your PILLS. Now... Since you installed a HOME DEPOT PIC-VALVE...; These are intended for water coolers and refrigerator applications...., You need to open that value up by un-screwing it counter-clock wise… (Yes Screw it COUNTER CLOCK WISE ). By doing so, you’ll open the valve, which will save your engine from certain destruction. Now, once you’ve done that, and assuming you have a boost gauge, you should see lower boost #’s… that is your reported BOOST numbers should be at safe, SANE Levels... Remember those 2 skinny black hoses I talked about earlier?.. that went to your ACTUATORS?.... GO GET EM. NOW, Put em Back (reinstall) the Longer one to the lower (MIDDLE) actuator. Make sure the stock PILL is in the hose, (Physically Look inside the hose and make sure the Pill's Hole is centered up). NOW, once you’ve done all that…. Go find yourself a GOOD ROTARY PERFORMANCE SHOP …. And buy a Mazda Shop Manual and RTFM. OR plan on spending LOTS of $$$$$ replacing engines….