Boost Problem!!!!!!!!

[Lorenzo]

I finaly made it to the track and would like a little input. I have a freshly built 231 with standard TRW forged pistons. A 218/218 hydrolic cam, fully ported heads and intake with big valves. A 70GTQ turbo with .85 exaust housing, modified fuel system with dual intank pumps and 83lbs injectors. A front mount intercooler with 3" pipeing, Terry houston down pipe with a full 3" exaust. I am useing a turbo 350 trans with a 3500 stall and I am tuneing the car with a Big Stuff 3. I am just learning the Big Stuff3.

This was my first time out with the car. I ran 1/8 mile and I made two passes. My best pass was a 7.58 at 89 mph. My sixty was a 1.69 with a 9lb lunch and the car only made 19lbs of bust on that pass. I have a new high boost acuator but that is all the boost I can get out of it. What can I do to make more boost and about how much boost should I need to run in the 6.60 to 6.70 range. I run 116 octane and the car felt great but just down on boost. HELP!!!!!!!!!!

 

[Tony Shoaff]

Did you port the turbo housing puck hole? Have you turned the rod on the wastegate in? You will need 25-26lbs of boost to run 6.60"s at least I did. How are you controlling the boost? Need more info.

 

[Lorenzo]

Boost

No it is not ported. I have the boost rod turned all the way in as far as it will go and all i can get out of it is 19lbs. I also have a new high boost acuator from precision turbo on the car.

 

[Tony Shoaff]

Port the Puck hole leaving only a 1/8th inch so the puck can seal.

 

[Tony Shoaff]

Another question how are you controlling the wastegate?

 

[Lorenzo]

Wast Gate

I am useing the stock set up with a hose running to the turbo and one to the boost selonoid on the valve cover.

 

[Tony Shoaff]

I would port the housing hole that the puck seals to then. That will let you build more boost. Correct anyone else?

 

[FreeBoost]

I'm confused. Boost control on a turbocharger is achieved by controlling the amount of exhaust gas going through the turbine - more exhaust, faster turbine, more boost. The puck covers the turbine bypass. Increasing the bypass capacity won't increase the amount of exhaust going through the turbine so it can’t increase the boost. It would help if the problem is boost creep cause by the bypass not having enough capacity.
There are two fundamental reasons for not being able to increase the boost – not enough exhaust flow or not being able to close off the bypass (control). From the description this shouldn’t be a problem – unless the engine is running way too rich. What’s left – control. The actuator being used is good but it’s not the control element, the solenoid and ultimately ECM is. The OEM ECM doesn’t read boost pressure so it can’t directly control it. All it does is control the fuel and spark. It uses the solenoid to keep the air/fuel ratio within program limits. There are lots of aftermarket boost controllers out there, most cost a bag full of money, but a first step should be a baby step to see if it’ll work. Try a cheap manual controller such as a graduated valve or a check valve. The graduated valves used to be around but I haven’t seen them for a while. RJC has a check valve type that pretty cheap.
Just my opinion And I have been wrong before.