Boost Control

[turbojimmy]

Hi all!

I can't seem to get more than 21-22 PSI out of my PT-61. My boost control is simple - a brass valve in between the turbo outlet and the wastegate actuator. With the valve open all the way (it's a big valve, I doubt it's a restriction) I can only get 21-22 PSI out of the turbo. With the valve about halfway shut I get 21-22 PSI. With it closed all the way it will go down to about 17 PSI. I'm pretty sure I have an HD actuator (how do I tell).

I'm not sure how long it's been like this, but I just ported the wastegate hole on the exhaust housing. Turbo still spooled like it should after I ported it so I didn't think it was leaking. I unhooked the boost from the wastegate actuator and took it for a spin. There's PLENTY of boost to be had and FAST. I don't think it's the wastegate port.

So what can I do? Different actuator? Different means of control?

Ideas would be appreciated. I still have the stock "Y" and solenoid that I can put back if need be.

TIA,
Jim

 

[V6POWER]

How tight is your actuator rod?

 

[turbojimmy]

How tight is your actuator rod?

Oops, forgot to mention that. I took it in 2 turns yesterday trying to get the boost up but it stayed at 21-22 PSI. I can't even connect it by hand anymore - need big pliers to grab it and hook it to the wastegate.

Jim

 

[Turbo Indian]

I had the same problem with my GTQ76 I now have switched to RJC controller. I've only made 2 passes with it since I got it at the Nationals, but I now can make at least 25 psi. I just have not had a chance to crank it up to about 30 psi.

 

[turbojimmy]

I had the same problem with my GTQ76 I now have switched to RJC controller. I've only made 2 passes with it since I got it at the Nationals, but I now can make at least 25 psi. I just have not had a chance to crank it up to about 30 psi.

I've heard people talk about the RJC controller but don't know how it works.

Today I put the stock "Y" on with my bleeder. I put the restricted leg on the turbo outlet. I hooked the bleeder valve up to one remaining leg and the actuator up to the last leg. I can't believe how fast it spools now. I'm such an idiot. I was living with this slow spool because I thought a PT-61 just spools slow. With the boost restricted the wastegate stays shut longer so it spools really quick. Now I can go as low as 20 PSI, but that's with the wastegate really tight. I can probably get it down to about 18 PSI if I mess with it. But I run 100 octane in it so it's fine. I have the boost up to 25 PSI with an Extender "alky" chip (23/21 timing) and it's not knocking (exhaust gas was 1638 on one test run, tho - not sure if I should be concerned). O2s are high-700s so it seems pretty happy.

I'll look into the RJC controller and see if it'll work for me.

Thanks,
Jim